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1
Jaskula, Piotr, Mariusz Jaczewski, Dawid Ryś, and Marek Pszczoła. "Field assessment of low-temperature cracks and bearing capacity of selected road sections in North-Eastern Poland." Transportation Overview - Przeglad Komunikacyjny 2018, no. 11 (November 1, 2018): 106–15. http://dx.doi.org/10.35117/a_eng_18_11_11.
Повний текст джерелаАнотація:
Article presents the comparison of performance of selected road sections in north-eastern Poland constructed under typical contract conditions, with the usage of High Modulus Asphalt Concrete and typical Asphalt concrete The field investigation comprised of the assessment of: the number of transverse thermal cracking, the bearing capacity and the load transfer coefficient around the thermal cracks. The FWD test confirmed lower deflections of the road sections constructed with base courses made of High Modulus Asphalt Concrete and presented two times higher values of the stiff ness modulus of those pavements. The load transfer coefficient for pavements constructed with base course made of High Modulus Asphalt Concrete indicated almost lack of load transfer around the thermal cracks. In was very surprising as the tested roads were quite new (2-7 years) and with high bearing capacity. The article was made on the basis of the paper presented on BESTInfra conference, which was held in Prague.
2
Ndi, Conrad Dieudonné Bébé, Boris Nouaye, Michel Mbessa, and Robert D. Friedman. "Geotechnical characterization of an innovative soil stabilization product (Aggrebind/Road Master) usable in the construction, rehabilitation and maintenance of road infrastructure and the construction of social housing in Cameroon." Journal of the Cameroon Academy of Sciences 17, no. 3 (May 25, 2022): 257–75. http://dx.doi.org/10.4314/jcas.v17i3.5.
Повний текст джерелаАнотація:
Building roads in developing countries has always been very expensive. An efficient and more affordable method is needed. AggreBind’s soil stabilization solutions, known as RoadMaster (RM1 / RM2) and AggreBind (AGB-WT/BT) are offered. The objective of the present study was to make a geotechnical characterization of this product with a view towards its use in the construction, rehabilitation and maintenance of road infrastructure in Cameroon.A series of laboratory tests were carried out; soil identification tests (particle size analysis, Atterberg limits), lift tests (Proctor and modified CBR test), determination of the optimum water content of the material, maximum dry density, immediate CBR index and the CBR index after immersion for 4 days.Only the 95% OPM CBR test was carried out on the soil with the additive AGB-WT/RM1 in order to characterize the effects of the product on the soil.In conclusion, AggreBind/RoadMaster can provide stable, dust-free roads and stabilized base courses for general roads and highways that meet or exceed the bearing capacity requirements of international road specifications. In addition, the use of this product reduces the cost of road construction by 40% to60% and increases in-situ load bearing capacity by 400% to 600%.
3
Gražulytė, Judita, Audrius Vaitkus, Egidijus Rytas Vaidogas, and Ovidijus Šernas. "Field Studies Of MSWI Bottom Ash As Aggregate For Unbound Base Course Mixtures." IOP Conference Series: Materials Science and Engineering 1202, no. 1 (November 1, 2021): 012016. http://dx.doi.org/10.1088/1757-899x/1202/1/012016.
Повний текст джерелаАнотація:
Abstract In the European Union, about 30–40 million tonnes of residues known as municipal solid waste incinerator (MSWI) bottom ash is generated and landfilled annually. To address the continuous growth of landfills and to implement zero waste and circular economy policies, researchers are researching ways to turn MSWI bottom ash into a useable resource. The conducted studies show that MSWI bottom ash is suitable for civil engineering, especially for roads, however there is a lack of field studies. As a result, MSWI bottom ash was used to construct unbound base course in heavy vehicles parking lot in 2018 and two pedestrian paths in 2018 and 2020 in Vilnius (Lithuania). This paper focuses on the structures composition and performance of those unbound base courses in terms of stability of particle size distribution, bearing capacity and permeability. The conducted study showed promising results for MSWI bottom ash as aggregate (mixture) to construct unbound base course.
4
Barbieri, Diego Maria, Baowen Lou, Hao Chen, Benan Shu, Fusong Wang, and Inge Hoff. "Organosilane and Lignosulfonate Stabilization of Roads Unbound: Performance during a Two-Year Time Span." Advances in Civil Engineering 2021 (September 30, 2021): 1–13. http://dx.doi.org/10.1155/2021/9367501.
Повний текст джерелаАнотація:
The construction of the new Norwegian E39 highway comprises the excavation of extended tunnelling systems, which lead to a tremendous amount of blasted rocks. Among others, a sustainable cost-benefit application of these resources is represented by their local use as construction material in the unbound layers of the roads. Two types of nontraditional additives are investigated to improve the mechanical properties of aggregates; this is particularly useful for those rocks that do not fulfil the design requirements in their natural status. This work focuses on the field application of two innovative stabilizing technologies based on organosilane and lignosulfonate. The performance of these additive agents is characterized by considering three typical road base layer sections built on purpose according to real practice and added with water (no treatment), organosilane, and lignosulfonate. The test sections are subjected to climatic actions only as neither traffic nor surface courses are applied. With the investigation covering two years, the layers’ stiffness, deformation, and resistance to penetration are evaluated by employing a light-weight deflectometer and dynamic cone penetrometer. Both organosilane and lignosulfonate significantly enhance the mechanical properties of the treated base layers.
5
Karaşahin, Mustafa, Cahit Gürer, Mehmet Saltan, Murat V. Taciroğlu, and Volkan Emre Uz. "Investigation of chip seal performance under cold climate conditions." Science and Engineering of Composite Materials 23, no. 6 (November 1, 2016): 649–58. http://dx.doi.org/10.1515/secm-2014-0041.
Повний текст джерелаАнотація:
AbstractThe chip seal is an economical type of asphalt pavement that was constructed for single- or double-layer aggregate-bitumen. Chip seals are applied to prime-sealed granular pavement surfaces in order to waterproof the surfaces of sub-layers, produce smooth and high-skid-resistance surfaces for vehicles and protect pavements against the detrimental effects of traffic and climate. Unlike bituminous hot mixtures, numerous factors can affect the performance of chip seal. One of the most important factors is climate. The aim of this study is to determine the performance variation of chip-sealed pavements under cold climate conditions. Three different chip-sealed roads in Erzurum, which is in one of the coldest regions of Turkey, were examined with non-destructive tests. Sand-patch, British pendulum, light weight deflectometer and dynamic cone penetrometer tests were performed. Chip-sealed pavements’ densities and surface temperature variation and base courses layer’s thicknesses were also measured, and deteriorations were observed and scored by researchers. Test results showed that flushing due to the higher temperatures during the short summer season, deficiency of the base course’s bearing capacity and moisture in the base course are the most important causes of deterioration in this type of chip seal, and the chip seals in this region must be resealed in <1 year because of the premature deterioration.
6
Zvonarić, Matija, Ivana Barišić, Tihomir Dokšanović, and Martina Zagvozda. "Preliminary Research On Waste Rubber Application In Cement Bound Base Layer." IOP Conference Series: Materials Science and Engineering 1202, no. 1 (November 1, 2021): 012047. http://dx.doi.org/10.1088/1757-899x/1202/1/012047.
Повний текст джерелаАнотація:
Abstract Besides all the positive characteristics of cement bound courses (CBC), it has some detrimental effects on the pavement wearing courses. Due to cement hydration, this mixture is affected by shrinkage. Shrinkage induces cracks in the whole layer which along with weather conditions propagate through asphalt layers in a short period. Also, it’s stiffness negatively affects cracks propagation without providing elastic support for upper layers. As a result, roads are covered with various damages which reduces driving comfort and safety and demand new financial investments. The focus is on reducing the detrimental effect of CBC on the pavement. Nowadays, large quantities of recycled rubber can be found on the market. Wasted rubber is a large ecological problem due to its long decomposition period. On the other hand, by mechanical grinding and separation process, suitable fractions of rubber can be obtained for use in construction. Consequently, the replacement of conventional material by crumb rubber reduces the consumption of natural material and energy for its exploitation. Appropriate amounts and fractions of recycled rubber have the potential to reduce shrinkage and increase the elasticity of CBC. Within this paper, preliminary research results will be presented on the possibilities of crumb rubber implementation in CBC and its effects on mechanical characteristics. By using recycled materials in construction processes we undertake a major step in the sustainable management of natural resources.
7
Han, Eui-Seok, Junho Gong, Hoseong Jeong, and Dooyong Cho. "Development of Bonded Natural Stone Pavement Using Ultra-Rapid-Hardening Mortar." Applied Sciences 10, no. 10 (May 21, 2020): 3576. http://dx.doi.org/10.3390/app10103576.
Повний текст джерелаАнотація:
Bonded natural stone pavement has been typically used in historical neighborhoods to satisfy functional and architectural aesthetic standards. Despite its advantages, it has been barely applied to places for heavy traffic volume or high travelling speed because of various structural failures in joints and bedding courses. Ultra-rapid-hardening mortar for natural stone pavement was considered as an alternative to minimize these failures. The objective of this study is to develop bound stone pavement using the ultra-rapid-hardening mortar for high traffic volume and evaluate throughout by carrying out material tests, plate load test, accelerated pavement test (APT), and falling weight deflectometer (FWD) test. For the tests, four types of pavements, asphalt, concrete block, and two bound stone pavements, were produced in a testing facility. The bearing capacity of the sub-base course, which was asphalt and concrete, showed values 1.62 and 2.64 times higher than deemed satisfactory. Additionally, rut depth was measured using a transverse profile logger during the APT test and the test was terminated at 1.97 million cumulative equivalent single axle loads (ESALs). In the rut depth measurements, the deepest deflection (16.0 mm) was made in the asphalt pavement and the depth of the concrete block pavement was 4.5 mm. Vertical displacements of 3.0 and 1.5 mm were obtained in stone pavements A and B, respectively. The maximum pavement vertical deflection response was recorded at 0, 0.4, and 1.97 million ESALs. The response results revealed that they were influenced by the material types of either bedding or sub-base courses. With these outcomes, it would be possible to apply the baseline data for designing rigid small element pavement for heavy traffic volume or high travelling speed roads.
8
Kokoszka, Wanda. "The Risk Assessment for a Single Building on the Landslide Areas and Floodplains." Civil and Environmental Engineering Reports 28, no. 4 (December 1, 2018): 36–48. http://dx.doi.org/10.2478/ceer-2018-0049.
Повний текст джерелаАнотація:
Abstract Mass movements and floods are natural hazards posing a threat to the environment and bring significant economic losses. The flooding and landslide are risks in the municipalities of south-eastern Poland. Long-lasting rains cause initialize process of landslides on the slopes above the river valley, as well as flooding of local infrastructures (buildings, roads, railway tracks) located near water courses. Monitoring of geotechnical and hydrological parameters of the area is the base for the prognosis, as well as the risk assessment associated with them. So, in the paper highlights the issue of the consistency of monitoring and warning systems for these two threats. For landslides work SOPO - System Guards Against Landslides. Hydrogeological bases are defined for floodplains as The Computer System of the National Guard - ISOK. However, notable is the lack of integrity of both systems. In this paper a proposal to determine the overall risk for both threats in case of a single building is presented.
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Casarin, Rui Donizete, and Eduardo Luiz de Oliveira. "CONTROLE DE EROSÃO EM ESTRADAS RURAIS NÃO PAVIMENTADAS, UTILIZANDO SISTEMA DE TERRACEAMENTO COM GRADIENTE ASSOCIADO A BACIAS DE CAPTAÇÃO." IRRIGA 14, no. 4 (June 18, 2018): 548–63. http://dx.doi.org/10.15809/irriga.2009v14n4p548-563.
Повний текст джерелаАнотація:
CONTROLE DE EROSÃO EM ESTRADAS RURAIS NÃO PAVIMENTADAS, UTILIZANDO SISTEMA DE TERRACEAMENTO COM GRADIENTE ASSOCIADO A BACIAS DE CAPTAÇÃO Rui Donizete Casarin1; Eduardo Luiz de Oliveira21Faculdade de Ciências Agronômicas, Universidade Estadual Paulista, Botucatu, SP, ruicasarin@ig.com.br2Departamento de Engenharia Civil, Universidade Estadual Paulista, Bauru, SP 1 RESUMO As estradas rurais de terra são estruturas viárias importantes para o desenvolvimento rural econômico e social da nação, sendo que a erosão provocada pelas águas das chuvas no seu leito e margens esta intimamente relacionada à má drenagem, tornando-se um dos principais fatores para sua degradação. Para que o sistema de drenagem funcione de forma adequada é necessário o conhecimento da erodibilidade, capacidade de infiltração de água no solo e adoção de práticas mecânicas de abatimentos de taludes com elevação do greide e interceptação de águas por meio de dispositivos de drenagem e captação. Neste artigo apresenta-se um modelo de drenagem por meio da construção de terraços embutidos com gradiente associados à bacia de captação em solos do tipo Argissolo Vermelho distrófico abrúptico de textura arenosa a média, com base em técnicas de abatimentos de taludes, elevando seu leito transversalmente das estradas com desviadores de fluxo. As frações granulométricas (areia, silte, argila) e a estabilidade de agregados indicam que esse solo sob ação antrópica pode apresentar processos erosivos resultando em escoamento superficial com arrastamento de solos, assoreando mananciais e cursos d’água localizados abaixo das estradas proporcionando grandes impactos ambientais nos corpos hídricos. A redução destes problemas de erosão nestas estradas de terra está na adoção de medidas que intercepte águas do próprio escoamento do seu leito, bem como as águas pluviais vindas de áreas adjacentes da contribuição, que são coletadas e conduzidas para terraços embutidos e bacias de captação. UNITERMOS: erosão em estradas rurais, infiltração de água no solo, práticas mecânicas de conservação de solo, contenção de águas pluviais. CASARIN, R. D.; OLIVEIRA, E. L. CONTROL OF EROSION IN RURALUNPAVED ROADS UTILIZING A TERRACE SYSTEM WITH GRADIENT ASSOCIATED TO CAPITATION BASIN 2 ABSTRACT The agricultural unpaved roads are important road structures for the economic and social agricultural development of the Nation, and the erosion provoked by rain water in the road bed and sides are closely related to bad draining, one of the main factors for their degradation. In order to make the draining system adequate, it is necessary to know about erodibility, infiltration capacity of water in the ground and adoption of mechanical slope abatement with grid elevation and water interception. This study presents drainage model through the construction of terraces with gradient transversally associated to the capitation basin in abruptic red dystrophic argisol soils, medium sandy texture, based on slops abatement techniques, elevating the road bed and deviating flow. The grain sized fractions of this ground (sand, silt, clay) and the aggregate stability indicated that this ground, under anthropic action, presents erosive processes resulting in superficial draining with ground hauling, sanding sources and courses of water situation below roads, providing great environmental impacts in the hydric bodies. The reduction of erosion problems in these unpaved roads is in the adoption of measures that intercept waters from the draining of their stream bed itself, as well as pluvial waters comings from adjacent areas of contribution, that are collected and conducted to inlaid terraces and capitation basis. KEYWORDS: erosion in agricultural roads, water infiltration in the soil, mechanical soil conservation practices, pluvial water containment.
10
Softić, Edis, Veljko Radičević, Marko Subotić, Željko Stević, Zlatan Talić, and Dragan Pamučar. "Sustainability of the Optimum Pavement Model of Reclaimed Asphalt from a Used Pavement Structure." Sustainability 12, no. 5 (March 3, 2020): 1912. http://dx.doi.org/10.3390/su12051912.
Повний текст джерелаАнотація:
This paper demonstrates and provides additional findings and instructions to produce new cold-recycled layers of pavement structures spatially and temporally sustainable. At the same time, recycled pavement structures have been enhanced with optimum amounts of new stone materials and binders made of cement and foamed bitumen. The subject of the research is based on the examination of recycled asphalt from surface and bituminous base courses of pavement structures for use on higher-type roads. The aim of the research is to model the process of producing recycled asphalt by cold recycling to optimize the process of influential parameters. In addition, one of the primary goals of the research is to demonstrate a sustainable way of producing new cold-recycled layers of pavement structures. The obtained results indicated the inevitability of the use of recycled material from pavement structures with the possibility of applying secondary and tertiary crushing of recycled mass, which depends on the type of layer for which the recycled material would be used. The research resulted in an optimum mixture variant of the stabilization layer of pavement structure that consists mainly of recycled material from a worn pavement structure improved with a relatively small amount of new aggregate with the addition of minimal stabilizers made of cement and foamed bitumen. The results showed that the optimum mixture variant of the stabilization layer is spatially and temporally stable. Additionally, the presented optimum variant of the stabilization layer enables sustainable development of road networks with minimum consumption of new natural resources.
11
Hasan, Aisha, Umair Hasan, Andrew Whyte, and Hamad Al Jassmi. "Lifecycle Analysis of Recycled Asphalt Pavements: Case Study Scenario Analyses of an Urban Highway Section." CivilEng 3, no. 2 (March 25, 2022): 242–62. http://dx.doi.org/10.3390/civileng3020015.
Повний текст джерелаАнотація:
Roads account for a major part of energy/resource consumption and emission of GHGs, such as CO2, PM, NOx, O3, etc., due to high demand for virgin materials, specifically in developing regions. The applicability of recycled materials, such as recycled asphalt pavement (RAP) and other alternative approaches for, e.g., warm-mix asphalt (WMA), in developed countries is hindered by project-specific constraints and lack of empirical studies in these regions. Lifecycle assessment studies on the usage of these road options from actual projects in the developing countries can aid decision makers choose sustainable material approaches by providing case study examples as guidelines. To that end, this study analyses environmental in/out-flows for a traditional approach and multiple green approaches (RAP and WMA) for a major highway section in Abu Dhabi through a 30-year (2015–2045) lifecycle approach. Roadworks were modelled in SimaPro according to real-world conditions, and the expected burden mitigation in each stage is calculated. Benefits of using optimum RAP-based options and a virgin-material-based WMA case against the baseline virgin material case were also investigated. Results showed benefits of WMA as higher than replacing virgin asphalt with recycled asphalt (25% RAP asphalt base, 15% RAP binder and wearing courses). Land use (19%) and energy consumption (16%) showed the highest reduction, followed by ozone depletion (14%), ionizing radiation (11%), PM (8%), acidification (7%) and global warming potential (6%) across all pavement lifecycle stages and environmental indicators. Similar results were obtained for other scenarios with lesser degrees of reduction, which show the significance of replacing HMA with WMA for real-world projects, specifically in mega road projects in Abu Dhabi and the Middle East towards cutting the significant carbon footprint of asphalt pavements.
12
Gardjito, Edy. "STUDY PERENCANAAN GEOMETRIK, PERKERASAN JALAN DAN PERENCANAAN ANGGARAN BIAYA PADA JALAN RAYA KALIDAWIR – Ds. NGUBALAN Kec. KALIDAWIR." UKaRsT 1, no. 2 (December 3, 2017): 11. http://dx.doi.org/10.30737/ukarst.v1i2.264.
Повний текст джерелаАнотація:
Kalidawir Highway Ngubalan Vilage which was originally a concrete rebate pavement located in the southern highland of Tulungagung City, is alternative road for local resident to go to the City area. So that the road can be sard to be guite crowded with traffic. So, here the author took the initiative to plane the road using flexible pavement. The hope for future, so it can be use as well as possible for the local Villagers. Even There included connecting roads between several villages.The method use in this planning is a method that is often used lag other planners, namely : Book Of Directorate General of Binamarga, 1970. Regulation Of Road Geometric Planning Directorate General Of Bina Marga, 1997. Procedures for planning geometric the inter city roads, The Center For Research and Development Jakarta, and use of others literature.The conclusion that can be get planning for this is, this way it is ±3.200 meter with width across 7 meter. Is available is 2 aligment horizontal PI 1 With radisius 200 meter as big as 34º33,5’5,82”. PI 2 radisius plan 150 meter as big as 34º4’22,29”. With surface course pavement = 5 cm, base course = 20 cm and sub base course = 15 cm.Keyword : Road Geometric Planning, Flexible Pavement and RAB
13
Hayadi, Hayadi, Irwan Lakawa, and Sulaiman Sulaiman. "Korelasi Nilai CBR Dengan kepadatan Lapangan Subbase Course." Sultra Civil Engineering Journal 2, no. 2 (December 9, 2021): 74–80. http://dx.doi.org/10.54297/sciej.v2i2.193.
Повний текст джерелаАнотація:
The durability of the road flexural pavement structure is largelydetermined by the performance of each layer. One of these factors isthe strength and resilience of the subbase. Compaction inaccordance with applicable standards will produce roads with goodquality so that the road life is longer and there is less damage. Thepurpose of this study is to analyze the carrying capacity using CBR,the value of the field density with the sand cone test and thecorrelation of the CBR value and the Sand cone value of the B gradefoundation layer on the Tugu Munajah network. The researchmethod used is laboratory and field testing combined with adescriptive statistic approach.The results of the study indicate that the carrying capacity using theCBR amounted to 55.02% <60%, the density value field with sandcone test of 72.50% <90%. Correlation of CBR and Sand cone value atthe base layer (sub base course) is very strong at 0.998.
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., Hayadi, Irwan Lakawa, and Sulaiman . "Korelasi Nilai CBR Dengan kepadatan Lapangan Subbase Course." Sultra Civil Engineering Journal 1, no. 2 (December 8, 2020): 1–8. http://dx.doi.org/10.54297/sciej.v1i2.140.
Повний текст джерелаАнотація:
The durability of the road flexural pavement structure is largelydetermined by the performance of each layer. One of these factors isthe strength and resilience of the subbase. Compaction inaccordance with applicable standards will produce roads with goodquality so that the road life is longer and there is less damage. Thepurpose of this study is to analyze the carrying capacity using CBR,the value of the field density with the sand cone test and thecorrelation of the CBR value and the Sand cone value of the B gradefoundation layer on the Tugu Munajah network. The researchmethod used is laboratory and field testing combined with adescriptive statistic approach.The results of the study indicate that the carrying capacity using theCBR amounted to 55.02% <60%, the density value field with sandcone test of 72.50% <90%. Correlation of CBR and Sand cone value atthe base layer (sub base course) is very strong at 0.998.
15
Žalimienė, Laura, Audrius Vaitkus, and Donatas Čygas. "Insights and Findings Following 11 Years of Test Road Exploitation." Coatings 10, no. 12 (November 28, 2020): 1161. http://dx.doi.org/10.3390/coatings10121161.
Повний текст джерелаАнотація:
Road pavement is one of the most important components of road structure. Long-term monitoring changes in the state of road pavement under real conditions of load and climate allows to determine surface degradation mechanisms, select sustainable road building materials and their mixes, rationally employ asphalt paving technologies, and improve quality control. For a number of years, road pavement structures have been studied that should best meet the Lithuanian climate conditions and withstand the increasing impact of vehicle load. Thus, for that purpose, specially designed, constructed and tested roads or road sections for different pavement structures are most appropriate. One of those was constructed in 2007. The experimental road (hereinafter, the Test Road) consisted of 27 different pavement structures (PSs) produced of various materials. The study aims to evaluate the effect of different materials on variations in the bearing capacity of the pavement structure (PS), the sustainability of the structure, and the formation of ruts in 2007–2018. In this way, difference in bearing capacity, rutting depth between sections, and loaded and unloaded lanes was estimated. Further, the statistical analysis of these factors was conducted. Investigations have shown that the minimum bearing capacity of 754 MPa established after 11 years did not affect the formation of rut depth that was less than 1.0 cm. The PSs covered with the used asphalt granules, a larger asphalt base course on gravel, the sand mix base course, and granite aggregate mixed with sand base course were accepted as one of the PSs with the highest bearing capacity with PSs exceeding 929 MPa. The bearing capacity of the PS containing a 20 cm aggregate base course is on average higher by 30 MPa than PS holding a 15 cm aggregate base course.
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Koźlarek, Piotr. "Monolayer asphalt pavement. Western requirements in Polish realities." Budownictwo i Architektura 13, no. 4 (December 9, 2014): 153–60. http://dx.doi.org/10.35784/bud-arch.1753.
Повний текст джерелаАнотація:
Polish road network is made up of 95% local roads. Their technical condition is much worse in comparison to motorways and national roads network. The lack of financial resources is one of the main reasons for this situation. That is why there is a continuous search for technologies, that allow for fast and cheap pavement repair or modernization. The monolayer asphalt pavement is such a solution offering in addition to cost effectiveness and shorter construction time, also an increased durability. Our western neighbors developed the technical regulations for this technology under the name "Asphalttragdeckschicht" which is marked as AC 16 TD. In direct translation "Asphalttragdeckschicht" means supporting wearing course / base layer. The monolayer asphalt pavement consists of a single layer with thickness between 5 to 10 cm made of HMA that links the functions of two layers – asphalt base course and asphalt wearing course. Thanks to this, the monolayer is resistant to environmental conditions and provides an adequate bearing capacity for a given traffic load. Insufficient funding and the impossibility to put the street out of operation were the bases for the investor’s decision to build a 220m section of road pavement using the monolayer pavement technology in Pruszków near Warsaw. This project gave the possibility to learn and gain an experience with a new western technology applied to Polish reality.
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Ullah, Saad, Burak F. Tanyu, Erol F. Guler, Edward J. Hoppe, and Emre Akmaz. "Evaluation of the Long-Term Performance of Woven Geotextile Used between Base Course and Subgrade of a Paved Road." Transportation Research Record: Journal of the Transportation Research Board 2673, no. 8 (April 25, 2019): 310–21. http://dx.doi.org/10.1177/0361198119827567.
Повний текст джерелаАнотація:
The purpose of this research was to investigate the properties of the exhumed geotextile from a low-volume road on the Virginia Department of Transportation network. The exhumed geotextiles have been in service for 23 years, which provided an opportunity to evaluate the longevity of the materials as well as to make assessments of how it relates to the changes in material properties. During this investigation, subgrade and base course materials were also obtained from the same site and an experimental program was developed to evaluate the effectiveness of the exhumed geotextiles for separation, stabilization, and filtration for the base course thicknesses of 4, 6, and 8 in. The results from this study combined with the results from the previous studies conducted at the same site showed that when the geotextile is placed between the subgrade and base course, the thinner the pavement section, the more evident the effectiveness of the geotextile improvements. One important finding of this research was that the placement of a geotextile reduced the particle breakage caused by abrasion under the applied transient loads. This was observed as a stabilization effect of the geotextile inclusion. As a general conclusion, for low-volume roads with relatively thin pavement sections, properly selected geotextiles provide benefits for separating the subgrade and base course (minimizing pumping), filtering infiltrated or ground water, and stabilizing the road profile. These benefits become more apparent when the thickness of the base course is less than 8 in.
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Hu, Jian Jun, Peng Ge, Zheng Bin He, and Da Tong Qin. "Modeling and Controlling of Anti-Slip Regulation Based on Limited-Slip Differential." Applied Mechanics and Materials 86 (August 2011): 762–66. http://dx.doi.org/10.4028/www.scientific.net/amm.86.762.
Повний текст джерелаАнотація:
The dynamic models of whole rear-wheel drive vehicle, limited-slip differential, hydraulic control system and electronic throttle were established. Simulations of acceleration course on split-µ road, checkerboard-µ road, low-µ road and step-µ road were carried out combining electronic throttle PI controller and limited-slip differential fuzzy controller. The results show that the Anti-slip Regulation quickly works according to the road adhesion coefficient, effectively inhibits the slip of driving wheels on low adhesion coefficient road, the acceleration performance driving on bad roads was improved obviously, and show a good adaptability.
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Randolph, Robert B. "Earth Materials Catalyst Stabilization for Road Bases, Road Shoulders, Unpaved Roads, and Transportation Earthworks." Transportation Research Record: Journal of the Transportation Research Board 1589, no. 1 (January 1997): 58–63. http://dx.doi.org/10.3141/1589-10.
Повний текст джерелаАнотація:
Frequency of use of concentrated liquid stabilizers to improve stability of aggregate and soil materials in constructing roads and other transportation-related structures is increasing. Concentrated stabilizers are formulated specifically for modification, improvement, and stabilization of aggregate and soil materials and require dilution in a water solution before application to allow for adequate dispersion. Applied costs of treatment are generally much less than conventional chemical stabilization treatment, because application is much simpler and product and transportation costs are less. Treatments are applied to aggregate materials to reduce base course and subbase structural sections and to strengthen resistance to repetitive loading and environmental factors. Gravel loss and maintenance frequency have been greatly reduced for unpaved roads and road shoulders. A report of these findings is timely, because both public and private sectors are seeking cost-effective treatments to improve long-term performance of conventional pavements and to help use limited budgets to address environmental regulations mandating dust control and sediment control for road shoulders and unpaved surfaces. Representative case studies of federal and state agency projects that used an earth materials catalyst (a concentrated liquid stabilizer) document the benefits of appropriate application of concentrated liquid stabilizer technology.
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Kriswardhana, Willy, Dewi Junita Koesoemawati, and Trio Sagita Susanto. "EVALUATION OF FLEXIBLE PAVEMENT DAMAGE DEGREE WITH PAVEMENT CONDITION INDEX METHOD (CASE STUDY: ARGOPURO ROADS - BANYUWANGI STA. 0+000 TO STA. 2+600)." Jurnal Rekayasa Sipil dan Lingkungan 2, no. 01 (July 5, 2018): 1. http://dx.doi.org/10.19184/jrsl.v2i01.6892.
Повний текст джерелаАнотація:
Argopuro Roads Banyuwangi Regency with a length of 2.6 km is a switching route for heavy vehicles and buses from the north of Banyuwangi to Jember. The increase in traffic volume from year to year as well as the construction of factories and warehouses along the roads resulted in a decrease in road capability to receive loads on it. To know the type and the extent of damage occurring on Argopuro Roads is done a research which will be able to determine the appropriate type of maintenance. The determination of road condition is done by Pavement Condition Index method (PCI). Road improvement is calculated by using the component analysis method from Department of Highways Regulation No. 378/KPTS/1987. Based on the result of research, the index value of pavement condition in survei by using PCI method is 58.07. The improvement of road is done in the segment with the failure condition to the fair with the handling of the improvement in the form of recontruction. Based on the calculation result in this research, it resulted that the pavement structure has thickness of 10 cm surface course, thickness of 25 cm base course, and thickness of 63 cm sub base course.
Ruas Jalan Argopuro Kabupaten Banyuwangi dengan panjang ruas 2.6 km merupakan jalur pengalih untuk kendaraan berat dan bus dari arah utara kota Banyuwangi menuju Kota Jember. Adanya peningkatan volume lalu lintas dari tahun ke tahun serta pembangunan sejumlah pabrik dan gudang pada sepanjang ruas jalan tersebut mengakibatkan menurunnya kemampuan jalan untuk menerima beban di atasnya. Untuk mengetahui jenis dan tingkat kerusakan yang terjadi pada ruas Jalan Argopuro, dilakukan penelitian yang dapat menentukan jenis pemeliharaan yang sesuai. Penentuan kondisi jalan dilakukan dengan metode Pavement Condition Index (PCI). Perbaikan jalan dihitung dengan menggunakan metode analisa komponen dari peraturan Departemen Bina Marga Nomor 378/KPTS/1987. Berdasarkan hasil penelitian, nilai indeks kondisi pekerasan jalan yang disurvei dengan menggunakan metode PCI yaitu 58,07. Perbaikan jalan dilakukan pada segmen dengan kondisi gagal (fail) hingga sedang (fair) dengan penanganan perbaikan berupa rekonstruksi. Berdasarkan hasil perhitungan pada penelitian ini menghasilkan struktur perkerasan jalan dengan ketebalan tebal lapis permukaan 10 cm, tebal lapis pondasi atas sebesar 25 cm, dan tebal lapis pondasi bawah setebal 63 cm.
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Liu, Kai, Fang Wang, Wei Hua Zhang, and Yuan Rong Wang. "Research on Material Selection Standard of Graded Crushed Stone Base Course for Municipal Road." Applied Mechanics and Materials 164 (April 2012): 81–84. http://dx.doi.org/10.4028/www.scientific.net/amm.164.81.
Повний текст джерелаАнотація:
For reasonably selecting graded crushed stone materials, material selection standard is proposed for each traffic level of municipal roads according to the local common material properties in Anhui province, and referring to technical index provision and research results about graded crushed stone material at home and abroad. The selection standard of coarse aggregate takes crushing value, abrasion value, needle and plate particle content and robustness as index. The selection standard of fine aggregate takes robustness, sand equivalent, liquid limit and plasticity index as index. The research results promote the popularization and application of graded crushed stone base course on municipal road engineering in Anhui province.
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Esho, Edire Erko, Emer Tucay Quezon, and Democracy Dila. "EFFECTS OF MECHANICALLY STABILIZED GRADED ASSORTED COARSE-GRAINED SOILS IN THE PERFORMANCE OF UNPAVED ROAD: A CASE STUDY IN GOFFA ZONE, SAWLA AREA." International Journal of Research -GRANTHAALAYAH 7, no. 8 (August 31, 2019): 133–56. http://dx.doi.org/10.29121/granthaalayah.v7.i8.2019.647.
Повний текст джерелаАнотація:
Road network development in Ethiopia is booming, radiating from Addis Ababa towards North-South directions, and East-West directions, due to the good economic growth of the country. However, there are challenges always facing by the pavement designers, and materials engineers for every road project, specifically the unpaved roads in Goffa Zone. It was because, most parts of the existing unpaved road sections within the study area are heavily damaged, and lack of proper maintenance. The source of good quality of sub-base course materials limited and becoming depleted. It is for this reason that the research study focused on the investigation of the effects of mechanically stabilized graded assorted coarse-grained soils. Disturbed and undisturbed samples from different quarry sites were considered and tested in the laboratory. Laboratory test for each location performed, and the results served as control values of the engineering properties of natural soils. The Disturbed samples tested for Gradation, Atterberg's Liquid Limit Tests, and Compaction, while, the undisturbed sample tested for the CBR strength, using ASTM manual. The results of the assorted materials for the sub-base course was analyzed and compared with the AASHTO and ERA Standard Specifications.
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Degu, Desta, Basha Fayissa, Anteneh Geremew, and Gelata Chala. "INVESTIGATING CAUSES OF FLEXIBLE PAVEMENT FAILURE: A CASE STUDY OF THE BAKO TO NEKEMTE ROAD, OROMIA, ETHIOPIA." Journal of Civil Engineering, Science and Technology 13, no. 2 (August 24, 2022): 112–35. http://dx.doi.org/10.33736/jcest.4332.2022.
Повний текст джерелаАнотація:
Most of the roads constructed in Ethiopia fail prematurely before serving the design life due to various causes arising from many factors. One of the roads that failed before reaching its design lifetime is the Bako to Nekemte Trunk Road. This road was constructed and opened to traffic in 2013. The design pavement life was estimated at 20 years. However; pavement failures have manifested since 2014 after it was opened for traffic. The main objective of this research was to investigate the cause for the failure of flexible pavement on the Bako to Nekemte road segment. To achieve this objective, the study was followed by the experimental research type and purposive sampling method. Also, field observation and pavement condition survey methods for data collection were used. The asphalt, base course, subgrade, and sub-base layer material sampled from the road segment are the material used for this study. Different pavement failures such as rutting, pothole, alligator cracking, raveling, edge cracking, depression, and corrugation were observed along the road section. For estimations of pavement condition index, the road was divided into five different sections based on distress densities, which were measured during the pavement condition survey. From those five sections, four sections were selected for the determination of the Pavement Condition Index (PCI). Using systematic random sampling 159 sample units were evaluated for Pavement Condition Rating (PCR) and the result shows 1.89% excellent, 8.18% very good, 20.13% good, 31.45% fair, 18.87 % poor, 18.24% very poor, and 1.26% failed. Based on PCI value, samples of pavement layer were taken from failed surface condition (1), poor surface condition (2), and none distressed area (1) for comparison purposes. Different quality tests like Atterberg limit, wash gradation, soil classification, compaction test, California Bearing Ratio (CBR), Los Angeles Abrasion (LAA), Flakiness Index ( FI), Aggregate Crushing Value (ACV), Ten percent fines value (TFV), bitumen content, and gradation of asphalt were carried out. The results of these tests were compared with ERA specifications to identify the probable cause of pavement failure. The study found that the cause for failure of flexible pavement in the case of Bako to Nekemte was: insufficient and absence of side drainage structure, traffic loading, poor gradation of base course and sub-base material, and poor quality of subgrade soil. The study also recommended that the road urgently needed routine maintenance as a treatment option to reduce further deterioration and extend its service time.
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Raut, Aditya, Sagar W. Dhengare, Ajay L. Dandge, and Harshal R. Nikhade. "Utilization of Waste Plastic Materials in Road Construction." Journal of Advance Research in Mechanical & Civil Engineering (ISSN: 2208-2379) 3, no. 3 (March 31, 2016): 01–12. http://dx.doi.org/10.53555/nnmce.v3i3.321.
Повний текст джерелаАнотація:
Plastics are user friendly but not eco-friendly as they are non biodegradable. Generally it is disposed by way of land filling or incineration of materials which is extremely risky. This waste plastic can be partially mixed with material use for road construction. In conventional road making process bitumen is used as binder. Such bitumen can be modified with waste plastic pieces. This waste plastic modified bitumen mix shows better binding property, stability, density and more resistant to water. Worldwide use of waste material in road construction is being increasingly encouraged so as to reduce environmental impact. The use of this innovative technology will strengthen the road construction and increase the road life as well as will help to utilization of waste plastic material. Plastic roads would be a blessing for hot and extremely humid climate, where temperatures normally cross 50°C and abundant rains create damage, leaving most of the roads with big potholes. The main aim of this study is to focus on using the available waste/recycled plastic materials and waste rubber tires present in abundant that can be used economically and conveniently. Using this technique for road construction proves ecofriendly, economical and use of plastic will also give strength in the sub-base course of the pavement.
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POŻARYCKI, Andrzej. "CONDITION ASSESSMENT OF LOWER ROADWAY LAYERS FOR PAVEMENT MANAGEMENT SYSTEMS." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 22, no. 3 (November 19, 2015): 311–21. http://dx.doi.org/10.3846/13923730.2014.897987.
Повний текст джерелаАнотація:
The process of selecting road maintenance technologies for the Pavement Management System (PMS) can use road pavement moduli of deformation as the substantiating information. Assessment criteria based on either pavement or base course moduli of deformation have strong empirical underpinning, since the stiff plate bearing testing (SPBT) is commonly used worldwide. This paper discusses potential practical applications of plate bearing test numerical simulation based on Falling Weight Deflectometer (FWD) deflection data, and theoretical model based on flexible pavement. It was proven that including a pavement model with stress dependency, the simulated second load-displacement curves meet reliably plate bearing in-situ test conditions for different layers of either subgrade or base courses of road pavement. This methodology is feasible by classifying technical condition of each lower layer of road pavement against requirements towards new pavements.
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Musa, Sarah Safaaldeen, Noorance Al-Mukaram, and Mohammed Bally Mahdi. "Assessment of Asphalt Mixture Behaviour Containing Recycled Concrete Aggregates." Key Engineering Materials 895 (August 3, 2021): 139–46. http://dx.doi.org/10.4028/www.scientific.net/kem.895.139.
Повний текст джерелаАнотація:
Recently, the construction industry uses the Recycled Concrete Aggregates (RCA)resulting from construction and demolition waste (CDW) to achieve sustainable requirements andeconomic benefits. In this paper, asphalt paving mixes were prepared with RCA instead of naturalaggregates for the base course in flexible road pavements and walking areas used by pedestrians andcyclists. Different asphalt mixes samples were prepared with different asphalt contents to meet therequired specifications. Additionally, several laboratory tests were carried out to assess mixturebehavior including the Marshall test. The results indicated that the mixture made with aggregates ofCDW have met all the requirements of Iraqi specifications of roads and bridges (SORB/R9). Thisinvestigation could be a useful guide for road engineers in designing asphalt mixtures from RCA.
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Hojjati-Emami, Khashayar, Balbir S. Dhillon, and Kouroush Jenab. "The HRA-Based Road Crash Data." International Journal of Strategic Decision Sciences 5, no. 4 (October 2014): 1–15. http://dx.doi.org/10.4018/ijsds.2014100101.
Повний текст джерелаАнотація:
Human error has played a critical role in the events precipitating the road accidents. Such accidents can be predicted and prevented by risk assessment, in particular assessing the human contribution to risk. As part of the Human Reliability Assessment (HRA) process, it is usually necessary not only to define what human errors can occur, but how often they will occur. Lack of understanding of the failure distribution characteristics of drivers on roads at any given time is a factor impeding the development of human reliability assessment and prediction of road accidents in order to take best proactive measures. The authors developed the complete investigation methodology for crash data collection. Furthermore, they have experimentally tested the proposed predictive behavioral characteristics of drivers in light of their instantaneous error rate over the course of driving period to assist processing and analysis of data collection as part of risk assessment. The findings of this research can assist road safety authorities to collect the necessary data, to better understand the behavioral characteristics of drivers on roads, to make more accurate risk assessments and finally to come up with right preventive measures.
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Akram, Suhail. "Unconventional and Simplified Approach towards Unpaved Roads: Application of Geosynthetics." International Journal for Research in Applied Science and Engineering Technology 9, no. 11 (November 30, 2021): 98–107. http://dx.doi.org/10.22214/ijraset.2021.38766.
Повний текст джерелаАнотація:
Abstract: A field trial was carried out to investigate the performance of different unconventional geosynthetic materials in unpaved road construction over soft ground.The test site comprises of 25 m long, by 3 m wide test sections, built on a subgrade of undrained shear strength approximately 45 kPa . One isunreinforced and serves as a control section in the study, three sections includea geotextile, and one includes a geogrid. Each test section incorporated avariable thickness of sandy gravel base course material, between25 and 45 cmthick. They were loaded in sequence by a vehicle of standard axle load.Performance of the test sections was evaluated from measurements of rut depth, base course thickness, base course deformations, geosynthetic strain, and deformed profile of the geosynthetic, with increasing number of vehicle passes.The four geosynthetic materials used exhibited a broad range of stiffness and material properties ,but the general performance of the four reinforced sections was similar on the base course layers. On contrary thinner subgrades showed a significant difference between the geosynthetics Keywords: Geo-synthetic materials, geo-textile, geo-grid, unpaved road.
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AKBULUT, Hüseyin, and Lale ATILGAN GEVREK. "Investigation of Stress Occurring in the Wearing Layer in Cases of Embedded Pipes in Different Layers in Asphalt Pavements with Hydronic Heating System." Afyon Kocatepe University Journal of Sciences and Engineering 22, no. 2 (April 30, 2022): 324–31. http://dx.doi.org/10.35414/akufemubid.1004772.
Повний текст джерелаАнотація:
In order to prevent snow accumulation and ice formation on asphalt concrete roads, the use of a hydronic heating system embedded in the pavement is recommended as an alternative to traditional snow and ice fighting applications. Hydronic heating systems circulate a heated liquid through a pipe network placed under the pavement layer to melt the snow and ice accumulated in the pavement layer, thus preventing the road surface from icing. Various parameters need to be evaluated for a reliable and economically viable hydronic snowmelt system. In this study, the stresses that occur as a result of traffic load in flexible pavements where hydronic heating systems are used and the stresses that occur as a result of traffic load in flexible pavements without hydronic heating system are compared using finite element software. Evaluations were made using five different air temperatures and three different inlet water temperatures. In the study, the stresses occurring in the surface course were investigated when buried pipes are located in the surface course, binder course, asphalt base course and gravel base layer. In addition, the stresses that occur as a result of traffic load in pe-x pipes used in the system were also evaluated.
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Zainal, Muzakir, Raihan Raihan, Muhammad Yanis, and Muksin Umar. "The Mapping of Road Pavement Structure around the Seismically Active Regions by Using Ground Penetrating Radar." Key Engineering Materials 940 (January 30, 2023): 145–52. http://dx.doi.org/10.4028/p-7mud9g.
Повний текст джерелаАнотація:
The Banda Aceh-Sigli Road has become the central infrastructure in connecting the capital city of Aceh province with other districts. In some places, the road construction was in rice fields dominated by high sedimentation areas. The Aceh also has the Great Sumatran Fault, which has caused many earthquakes and damaged public infrastructure, including roads. The density of the soil structure as an infrastructure buffer needs to be observed before road damage can endanger the community. This study aimed to apply Ground Penetrating Radar (GPR) as a non-destructive method that detects subsurface conditions based on permittivity parameters. The method is measured using the IDS Georadar Opera Duo instrument, which operates with a frequency of 250 MHz and 750 MHz for a penetration depth of 4 m, which is measured on eight intersecting tracks, where two profiles have a length of 110 m measured in the direction of the road segment and five tracks with a length of 11 m is measured by a cross. GresWin2 software is used for optimal analysis and modeling of 2D radargram. The radargram model describes a subsurface structure consisting of three layers, where the first layer with a depth of 0 – 0.25 m is asphalt, and the second and d layer with a depth of 0.25 – 0.75 m was identified as the base course layer. In comparison, the third layer is interpreted as a sub base course layer at a depth of 0.75 - 4 m below. The analysis results also show a linearly damaged road structure with high propagation speed and large wave amplitude. Therefore, based on data processing, it can be concluded that the application of GPR is a non-destructive, fast, and economical method for evaluating road structures.
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Ćwiąkała, Michał, Andrzej Greinert, Joanna Korzeniowska, and Paweł Tarasewicz. "The advantage of virgin soil in rural service road constructions." Budownictwo i Architektura 12, no. 3 (September 11, 2013): 129–36. http://dx.doi.org/10.35784/bud-arch.2009.
Повний текст джерелаАнотація:
Virgin soils as a result of geotechnical processes are element of road’s solid bottom. The bottom ought to have enough capacity and durability which is provided by proper virgin sub-grade’s enhancement. The sub-grade is road’s base course right bottom. It is possible to improve virgin soil’s parameters by road’s hydraulic binding agent. The agent is a mineral frame’s micro-particle extender or enhancement. The researches were focused to define main soil-cement compound’s mechanical parameter called CBR. Compounds consisted of rural virgin soils (five grain-size types) and two hydraulic agent types (endurance rates 3 MPa and 9 MPa). Hydraulic agent’s main component was activated fly ash and white cement (CEM I 42,5 MPa). The ash is from Pątnów Power Plant and is a result of brown coal burning. The researches answered that it is possible to exploit virgin soils in rural service road’s construction thanks to innovative road cements with binding qualities.
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Vaitkus, Audrius, Judita Gražulytė, Igoris Kravcovas, and Rafal Mickevič. "Comparison of the Bearing Capacity of Pavement Structures with Unbound and Cold Central-Plant Recycled Base Courses Based on FWD Data." Sustainability 13, no. 11 (June 2, 2021): 6310. http://dx.doi.org/10.3390/su13116310.
Повний текст джерелаАнотація:
Bearing capacity changes over the year, depending on the water content in a pavement structure: the higher the water content, the lower the bearing capacity. As expected, the highest water content in a pavement structure is observed in the early spring as the ice lenses melt. Thus, spring is a critical period for pavement performance, because a decrease in bearing capacity results in faster pavement deterioration. The bearing capacity of pavement structures with an unbound base course and the negative effect of spring thawing on pavement performance have been analyzed by a considerable number of researchers. However, very little is known about the bearing capacity of pavement structures with a cold-recycled base course despite the significantly increasing usage of cold-recycled mixtures. This paper focuses on the bearing capacity of both unbound and cold central-plant recycled base courses at different seasons and their stability. A cold central-plant recycled (CCPR) base course was constructed from a mixture of 38.8% reclaimed asphalt pavement (RAP), 3.1% foamed bitumen and 2.3% cement. A virgin aggregate was added to achieve desirable aggregate gradation. The bearing capacity of the unbound and CCPR base layers, as well as the whole pavement structure, was evaluated by back-calculated E moduli from falling weight deflectometer (FWD) data. In addition to this, the residual pavement life was calculated using mechanistic-empirical pavement design principles. The results showed that the durability of pavement structures with a CCPR base course is more than seven times lower compared to that of pavement structures with an unbound base course, irrespective of season. Nevertheless, the bearing capacity (surface modulus E0) of the pavement structure with a CCPR base course gradually increases due to the curing processes of bituminous and hydraulic binders (in this study, within four years of operation, it increased by 28–47%, depending on the side of the road).
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Wen, Haifang, Mathew P. Tharaniyil, and Bruce Ramme. "Investigation of Performance of Asphalt Pavement with Fly-Ash Stabilized Cold In-Place Recycled Base Course." Transportation Research Record: Journal of the Transportation Research Board 1819, no. 1 (January 2003): 27–31. http://dx.doi.org/10.3141/1819b-04.
Повний текст джерелаАнотація:
Class C fly ash is a coal combustion product from lignite or subbituminous coal obtained as a result of the power generation process. In recent years, efforts have been made to incorporate self-cementing fly ash into cold in-place recycled (CIR) asphalt material to improve the structural capacity of asphalt pavement base layers. In this study, asphalt pavements in County Trunk Highway JK in Waukesha County, Wisconsin, were pulverized in place and mixed with fly ash and water to function as a base course. To evaluate the contribution of fly ash to the pavement’s structural performance, nondestructive deflection tests were performed with a KUAB 2m-FWD falling weight deflectometer (FWD) on the outer wheelpath right after construction. The MICHBACK program was used to backcalculate the material properties of pavement layers from FWD measurements of deflection. The average moduli of the materials in the hot-mix asphalt layer, fly ash–stabilized base course, and subgrade were backcalculated. The structural capacity and structural number were also obtained from FWD test data. The structural coefficient of 0.16 was obtained for the fly ash–stabilized base course in the highway. The results of FWD testing indicate that CIR stabilization with self-cementing fly ash is an economical method of recycling flexible pavements and eliminates the need for expensive new granular base courses for road reconstruction.
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Corley-Lay, Judith B. "Comparison of Road Mix and Plant Mix Cement-Treated Aggregate Base Course." Transportation Research Record: Journal of the Transportation Research Board 1589, no. 1 (January 1997): 76–82. http://dx.doi.org/10.3141/1589-13.
Повний текст джерелаАнотація:
A study was undertaken to determine the advantages of plant mix over road mix cement-treated aggregate base course (CTABC). Ten projects known to have cement-treated base course were selected. Each had been tested with a falling-weight deflectometer and had been cored to determine layer thicknesses and properties either in the past or as part of the current effort. Three possible benefits were considered: improved uniformity of material properties, reduced deflections, and increased strength or stiffness. Neither the coefficient of variation nor a developed uniformity coefficient showed a significant difference between plant mix and road mix. Plant mix resulted in lower average deflections and lower deflections when sites were compared with equal thicknesses of asphalt above the base course. However, road mix sites had higher compressive strengths than did plant mix sites. Backcalculated moduli for CTABC were higher for plant mix than for road mix, but the elastic moduli were similar for plant and road mix when determined by pulsevelocity testing. It was concluded that no clear benefit could be determined from using plant mix based on the sample of 10 projects, although the benefit of an adequate thickness of asphalt above the CTABC was clearly demonstrated.
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Li, Yue Jun, Liang Li, and Han Cheng Dan. "Study on Application of TerraZyme in Road Base Course of Road." Applied Mechanics and Materials 97-98 (September 2011): 1098–108. http://dx.doi.org/10.4028/www.scientific.net/amm.97-98.1098.
Повний текст джерелаАнотація:
Biological enzyme used for catalyzing reaction of soil is a new material which is completely different from traditional highway material. The solidification mechanism, construction technique and maintenance technique of TerraZyme solidifying the base course of pavement have been discussed and with respect to which the field tests have been studied in this paper. The analysis and test results showed that the advantages of the technique of TerraZyme solidification are no pollution, convenient construction, high strength of solidification, good water stability and low cost. Thus, it has significant social and economic benefits and bright future in practice.
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Yao, Jianming, Wei Wang, and Xuyan Song. "Performance of cement stabilized recycled aggregate base course added with metakaolin." E3S Web of Conferences 341 (2022): 01009. http://dx.doi.org/10.1051/e3sconf/202234101009.
Повний текст джерелаАнотація:
In order to better use the old cement concrete pavement materials in the cement stabilized base of the reconstruction or new road. In this paper, metakaolin was used to replace recycled fine aggregate with different proportions to prepare cement stabilized recycled aggregate base mixture, and the physical and mechanical properties and dry shrinkage properties of cement stabilized recycled aggregate base mixture were studied. The results of the study show that adding a proper amount of metakaolin can reduce the optimal water content of the mixture, increases the maximum dry density and 7d unconfined compressive strength of the mixture, and also reduces the total water loss and dry shrinkage of the mixture. The research results can provide new ideas for the recycling of road waste materials.
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Tan, Guojin, Zhiqing Zhu, Yafeng Gong, Chenglin Shi, and Ziyu Liu. "Performance Evaluation of Cement-Stabilized Oil Shale Semicoke as Base or Subbase Course Construction Material." Advances in Materials Science and Engineering 2018 (2018): 1–12. http://dx.doi.org/10.1155/2018/2382596.
Повний текст джерелаАнотація:
Oil shale semicoke is a hazardous byproduct in oil shale retorting process. In Jilin province, China, abundant oil shale resources are mainly used for retorting shale oil accompanying with a large number of oil shale semicoke slags, which will generally cause environmental pollution and disposal problems. If oil shale semicoke can be utilized as a road base or subbase course construction material, it will be a great help to the disposal of a long-term accumulated oil shale semicoke in landfill sites. Moreover, the resource treatment of oil shale semicoke in road project construction could obtain positive social and economic benefits. Subsequently, we conducted a series of laboratory tests to study the practicability of cement-stabilized oil shale semicoke as a road base or subbase course construction material, including the raw material test, modified compaction test, unconfined compressive strength (UCS) test, splitting tensile strength (STS) test, compressive resilient modulus (CRM) test, and freezing-thawing test. In this paper, test results were compared with the technical requirements of Chinese road base construction specification, preliminarily confirming that cement-stabilized oil shale semicoke can be used as a subbase course material of a highway or a base course material of a low-grade highway.
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Tsynka, Anatolii, Serhii Illiash, and Volodymyr Zelenovskyi. "IMPROVEMENT OF BUILDING CODES FOR QUALITY DESIGN AND CONSTRUCTION OF ROADS." Dorogi i mosti 2022, no. 25 (March 17, 2022): 110–31. http://dx.doi.org/10.36100/dorogimosti2022.25.110.
Повний текст джерелаАнотація:
Abstract Introduction. This article considers the issue of modernization of the regulatory and technical base of the road sector in the design and construction of streets and roads of settlements and public roads (hereinafter - highways) on the basis of analysis of existing regulations, regulations, technical literature, which refers to the objects of regulation and, of course, taking into account the requirements dictated by today's safety and environmental protection. The work concerns the basic building codes for the design and construction of roads, namely those innovations that have already been approved and are planned to be put into operation in the near future. Problem statement. Implementation of a common technical policy in road construction, ensuring their reliability and durability, increasing the efficiency of capital investments, implementing the provisions of Directive 2008/96 / EC of the European Parliament and of the Council on Road Infrastructure Safety Management, harmonizing international and European standards, implementing scientific and technical standards achievements of science and advanced domestic and world experience in the practice of design and construction, saving material, labor, financial and energy resources, improving design solutions, construction quality, occupational safety and health, rational use of land, other natural resources and environmental protection, encourages the continuous improvement of state building codes, as fundamental documents for the design and construction of roads. Objective. The main documents governing the requirements for the design and construction of roads, namely DBN B.2.3-4: 2015 "Roads. Part I. Design. Part II. Construction ", which were republished in 2015 and DBN B.2.3-5: 2018" Streets and roads of settlements ", republished in 2018, taking into account the current traffic intensity, increased requirements for the load on pavement, safety requirements and environmental protection, as well as the development of regulatory and technical framework, developed appropriate changes and additions. In order to reveal and detail their essence, effectiveness and purposefulness, the relevant material developed in this article has been developed. Materials and methods. The presented work is based on analytical, practical and theoretical research related to standardization requirements for the design and construction of streets and roads of settlements and public roads. Results. Amendments to the state building norms have been developed, which set requirements for the design and construction of streets and roads of settlements and public roads, taking into account modern design requirements, the latest materials and technologies. Conclusions. The requirements set out in the developed amendments to the state building codes for the design and construction of streets and roads of settlements and public roads are internal indicators. They are formed by complex analytical and practical calculations from many variables and unknowns, numerous public meetings and legal meetings, long-term coordination with central executive bodies, there are complex expert verification of the basic organization that implements scientific activities in construction and approval. Huge amounts of statistics and the best world and domestic experience were used to achieve the end result. Based on the results of the work performed, the most optimal requirements have been established, the main requirements that regulate the principles of design and construction of high-quality roads in Ukraine according to modern European standards. Keywords: building norms, public highways, streets and roads of settlements, design of highways, construction of highways, changes to building norms.
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Tettamanti, Tamás, Alfréd Csikós, Krisztián Balázs Kis, Zsolt János Viharos, and István Varga. "PATTERN RECOGNITION BASED SPEED FORECASTING METHODOLOGY FOR URBAN TRAFFIC NETWORK." Transport 33, no. 4 (December 5, 2018): 959–70. http://dx.doi.org/10.3846/16484142.2017.1352027.
Повний текст джерелаАнотація:
A full methodology of short-term traffic prediction is proposed for urban road traffic network via Artificial Neural Network (ANN). The goal of the forecasting is to provide speed estimation forward by 5, 15 and 30 min. Unlike similar research results in this field, the investigated method aims to predict traffic speed for signalized urban road links and not for highway or arterial roads. The methodology contains an efficient feature selection algorithm in order to determine the appropriate input parameters required for neural network training. As another contribution of the paper, a built-in incomplete data handling is provided as input data (originating from traffic sensors or Floating Car Data (FCD)) might be absent or biased in practice. Therefore, input data handling can assure a robust operation of speed forecasting also in case of missing data. The proposed algorithm is trained, tested and analysed in a test network built-up in a microscopic traffic simulator by using daily course of real-world traffic.
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Hornikovska, Iryna, and Vadym Kahanov. "Non-autoclaved foam concrete for layers of highways surface dressing." Theory and Building Practice 2020, no. 2 (November 20, 2020): 35–41. http://dx.doi.org/10.23939/jtbp2020.02.035.
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The article is devoted to the problems associated freeze with the calculated estimation of the parameters of the structural and heat-insulating antifreeze layer in the subgrade of non-rigid roads on various soil bases. The main physical, technical and deformation characteristics of monolithic dispersed non-autoclaved foam concrete reinforced with polypropylene fiber of grades of density from 600 to 1000 kg/m3 are investigated. Freezing of subsoil waters directly under the roadway pavement and, as a result, its increase in volume, leads to significant deformations of the road surface. Under such conditions, the period of defectfree operation of the roadway pavement is significantly reduced, which in turn leads to the need to repair it in a more intensive mode. One of the ways to reduce the operating cost and maintenance costs of the road transport infrastructure is to introduce into the design and construction practice new structural concepts for road surface dressing that ensure high quality pavement during the normative operational period. This can be achieved by introducing an effective heat-insulating material into the pavement structure as an anti-frost layer in order to elimi-nate the effect of frost lift of the roadway pavement of non-rigid roads. Since domestic and foreign experience freeze in the road construction has proven the effectiveness of the use of heatinsulating materials in the road surface dressing construction, in recent years in Ukraine there has been increased interest in the use of non-autoclaved foam concrete as a modern and highly effective heat-insulating material in road construction. The installation of a heat-insulating layer made of non-autoclaved foam concrete allows us to completely or partially prevent freezing or overheating of the surface dressing base, reduce the influence of periodic variations in environmental temperature, which in turn will increase the durability of the pavement structure. The publication presents nomograms for determining the optimal thickness of the heat-insulating anti-frost heavy course (layer) of road surface dressing (based on sand, loamy sand, clay and loam) done at the street and road network for all climatic and geographical regions of Ukraine.
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Manamgoda, Manamgoda Gamage Nimantha, B. A. K. S. Perera, and Colombapatabendige Savindi Ranthika Perera. "Impact of interest rates of bank loans on road construction: the case of Sri Lanka." Journal of Engineering, Design and Technology 16, no. 4 (August 6, 2018): 518–32. http://dx.doi.org/10.1108/jedt-12-2017-0133.
Повний текст джерелаАнотація:
Purpose Infrastructure systems play a dominant role in the economic growth of countries. Projects involved with the construction of roads, which is vital for the development of a country, are financed mainly using borrowed funds because of the reliability of debt financing. The cost of borrowing is the interest that has to be paid. In Sri Lanka, there is a high tendency for interest rates of bank loans to fluctuate, and this makes the road projects in the country that are funded with borrowed money to be highly risky. Thus, this paper aims to identify the impact of bank loan interest rates on road construction in Sri Lanka. Design/methodology/approach The study consisted of two questionnaire surveys conducted among financial specialists and road construction experts, followed by a documentary review. The collected data were analysed using Relative Importance Index. The relationship between the interest rates of bank loans and the prices of the resources used in road projects were determined using regression and correlation analyses. Findings The research revealed a strong, linear relationship between interest rate fluctuations and bitumen, aggregate base course, metal and earth price fluctuations. It also identified the pattern of interest rate fluctuations to help practitioners to predict the pattern of input price variations. Originality/value When developing the capital structure of road projects, it is necessary to consider the prices of materials used in the projects when determining the financial risks of debt financing.
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Arratia-Martinez, Nancy M., Paulina A. Avila-Torres, and Juana C. Trujillo-Reyes. "Solving a University Course Timetabling Problem Based on AACSB Policies." Mathematics 9, no. 19 (October 6, 2021): 2500. http://dx.doi.org/10.3390/math9192500.
Повний текст джерелаАнотація:
The purpose of this research is to solve the university course timetabling problem (UCTP) that consists of designing a schedule of the courses to be offered in one academic period based on students’ demand, faculty composition and institutional constraints considering the policies established in the standards of the Association to Advance Collegiate Schools of Business (AACSB) accreditation. These standards involve faculty assignment with high level credentials that have to be fulfilled for business schools on the road to seek recognition and differentiation while providing exceptional learning. A new mathematical model for UCTP is proposed. The model allows the course-section-professor-time slot to be assigned for an academic department strategically using the faculty workload, course overload, and the fulfillment of the AACSB criteria. Further, the courses that will require new hires are classified according to the faculty qualifications stablished by AACSB. A real-world case is described and solved to show the efficiency of the proposed model. An analysis of different strategies derived from institutional policies that impacts the resulting timetabling is also presented. The results show the course overload could be a valuable strategy for helping mitigate the total of new hires needed. The proposed model allows to create the course at the same time the AACSB standards are met.
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Wang, Qing, and Yongxiang Ren. "Research on Teaching Strategy of Roadbed Structure and Construction Course Based on BIM Technology." Lifelong Education 9, no. 6 (September 28, 2020): 72. http://dx.doi.org/10.18282/le.v9i6.1302.
Повний текст джерелаАнотація:
The roadbed structure and construction course is a compulsory course for the major of road and bridge engineering technology in higher vocational colleges. The content of the course is theoretical, the formula is complex, and it is difficult to understand, which increases the difficulty of students’ learning, especially under the traditional “indoctrination” theoretical teaching mode , Classroom teaching efficiency is low, and students tend to lose interest and confidence in learning. With the application of BIM technology, students were visually shown the relationship between subgrade structure and construction components and construction links, with remarkable results. This article focuses on the problems related to the teaching of roadbed structure and construction courses based on BIM technology.
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Yan, Zhan You, Yu Shu, Jian Qing Bu, and Xiang Guo Li. "Test on the Performance of Road Base-Course Made of Steel Slag and Fly Ash." Advanced Materials Research 168-170 (December 2010): 2078–81. http://dx.doi.org/10.4028/www.scientific.net/amr.168-170.2078.
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Fly-ash is an industrial waste burning pulverize coal boilers for thermal power plant and large enterprises, the steel slag is too a residue generated waste in steelmaking industrial processes, the average for every ton steel to produce half ton steel slag, steel slag and fly ash discharge amounts is very big, utilization ratio is very low. At present, a large number of steel slag is used of reclamation work, the remaining items is used rarely and large number is left storage. This paper is introduction steel slag and fly ash to do road base-course material, such can make good use of industry residue waste in large amount to reduce exploitation and cut down natural building stones, it is an application for ecological building materials again. Major study the steel slag and fly ash road features, these tests include materials compaction reality among them, mix design, unconfined compressive strength, split tensile strength, resilient modulus and other commonly used performance. Through comparative analysis, this two materials combination has good use of quality, it has greatly better than other materials such as lime-fly-ash stabilize crushed stone and lime-fly-ash soil and other materials. In particular, it has very good performance to reduce road base-course crack, the material has good resistance shrinkage and temperature shrinkage ability. Therefore, the combination of steel slag and fly ash can be done entirely road base-course and extend the road life.
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Ardalan, Nazanin, Douglas J. Wilson, and Tam J. Larkin. "Analyzing the Application of Different Sources of Recycled Concrete Aggregate for Road Construction." Transportation Research Record: Journal of the Transportation Research Board 2674, no. 8 (June 22, 2020): 300–308. http://dx.doi.org/10.1177/0361198120924664.
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Because of the environmental, planning, and resource restrictions in the exploration and processing of natural aggregates, interest in better utilizing recycled aggregates in road pavement construction is increasing. Several researchers have investigated the characteristics of recycled concrete aggregate (RCAg) with the aim of understanding its performance as a base-course unbound material. As the pavement design techniques and the properties of re-processed RCAg in each country are non-homogeneous, previous international research on recycled aggregate cannot necessarily be incorporated in New Zealand’s pavement specifications. Moreover, RCAg is mainly sourced from vertical or horizontal concrete demolished structures. These sources of material have different engineering characteristics, and there is a lack of information about their performance. This paper investigates the difference between the properties of these two vertical and horizontal sources, and it evaluates their application as an unbound granular base-course material as opposed to an alternative layer in the pavement, for road construction in New Zealand. The physical properties of RCAgs engineering performance (durability) were evaluated through experimental laboratory-based tests. Also, the characteristics of the tested RCAgs were compared with the specification of base-course materials (NZ Transport Agency M4) in New Zealand, and their appropriateness for high-performing pavement construction layers was assessed. According to the tests results, the tested RCAgs have proven to meet the “premium” base-course grade product, and it is expected that recycled crushed concrete, if production processes are appropriately managed, could have great potential use as a base-course material in road construction and in some cases perform better than common natural aggregates.
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Mudrychenko, Anatolii, Andrii Hrinchuk, Ivan Balashov, and Sergey Illyasch. "Use of soils and recycled industrial products treated with water glass in the road pavement base courses." Dorogi i mosti 2021 (March 25, 2021): 86–93. http://dx.doi.org/10.36100/dorogimosti2021.23.086.
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Introduction. Growing volumes of road construction increase the need to expand and rationally use of raw materials. The need for stone materials can be solved through the wide spread using of local materials, recycled products of industry in the pavement base courses and decreasing the use of natural construction materials by replacing them with alternatives, including soils, slag materials that are metallurgical industry wastes. Experience of ferrous metallurgy slag usage has been accumulated in the road industry of Ukraine. Their usage makes it possible to extend the construction season, increases the strength and reliability of road structures due to their physical and mechanical properties, significantly reduces the road pavement energy consumption, simplifying the technology of works and the estimated cost of road construction. It was determined that the layers of pavement made from blast furnace slag have a high bearing capacity. Slag structures in 5–10 years of hardening are not inferior to, and in 10–20 years surpass cement structures on durability and deformation resistance. However, there is an urgent need to provide strength and open road traffic on the already built road section in a shortest possible term, so there is a need to accelerate the activation of the slow-setting binder. Therefore water glass (water solution of sodium silicate) is used.Purpose. The purpose of the work is to study the feasibility of using the soils and recycled industry products treated with water glass in the road pavement base courses.Materials and methods. Experimental tests of soils and blast furnace slags treated with water glass with different content of water solution of sodium silicate were performed.Results. The feasibility of using the asphalt concrete mixtures on the basis of soils and recycled products of industry treated with water glass in the pavement base courses is determined. Recommendations regarding technological parameters of preparation, transportation, laying and compaction of such mixes are given.Conclusions. Performed studies have shown that the physical and mechanical parameters of soils and blast furnace slags treated with water glass meet the requirements of current regulations of Ukraine. The advantages of use are noted, namely: the possibility of replacement of traditional stone materials by the local materials and recycled products of industry, reducing the transport component in the cost of construction. The obtained results indicate the feasibility of using the soils and recycled products of industry treated with water glass in the road construction.Keywords: soils, recycled products of industry, graded blast furnace slag, water solution of sodium silicate, water glass
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Wang, Fu Jun, Jing Luo, and Hui Rong Zhu. "Experimental Study in Gangue Base-Course Mixture Materials for Pavement." Advanced Materials Research 860-863 (December 2013): 1270–73. http://dx.doi.org/10.4028/www.scientific.net/amr.860-863.1270.
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Coal gangue, acting as the solid skeleton of pavement base materials, can efficiently reduce the drying shrinkage. Additionally, similar to fly ash in mixture material, gangue can react with lime (so called pozzolanic reaction), resulting in the formation of pavement base with a certain strength, good water stability and frost resistance, are good overall at the grass-roots level. Many cities in our country has gradually tried to use different kinds of industrial waste residue instead of sand to prepare the pavement base materials. This way, not only the waste residue is recycled, the lack of sand aggregates in road construction can also be overcome, which facilitate technical and economic growths.
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Lyons, C. Kevin, and Jonathan Fannin. "A comparison of two design methods for unpaved roads reinforced with geogrids." Canadian Geotechnical Journal 43, no. 12 (December 1, 2006): 1389–94. http://dx.doi.org/10.1139/t06-075.
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The design of geosynthetic-reinforced unpaved roads is based on a limit equilibrium analysis of bearing capacity at the ultimate limit state. Two semiempirical design methods are shown to be predicated on a common fundamental relation, but differ in the parameterization of input groups. Degradation of subgrade strength with repeated loading is well characterized by each design method and is believed to be of primary importance in obtaining good agreement between the result from analysis and the observed response to field trafficking. The two design methods were found to require different values for the undrained shear strength of the subgrade, which is partly attributed to the significantly different load spread angles used to model the effect of the base course. Selection of the initial undrained shear strength deserves careful consideration in sensitive soils. In order to use one of the design methods, it is important to select this value so that it is consistent with the other parameter groups being used.Key words: bearing capacity, geogrid, unpaved road.
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Konieczna, Katarzyna, Piotr Pokorski, Wojciech Sorociak, Piotr Radziszewski, Dawid Żymełka, and Jan Król. "Study of the Stiffness of the Bitumen Emulsion Based Cold Recycling Mixes for Road Base Courses." Materials 13, no. 23 (December 1, 2020): 5473. http://dx.doi.org/10.3390/ma13235473.
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The benefits of the use of cold recycling mixtures (CRMs) in pavement rehabilitation are associated with both the reduction of natural resource consumption by replacing them with recycled materials and the reduction of energy consumption during their production and paving. The evolution of the stiffness of CRMs in road construction and the fatigue life of pavements with CRM base layers are still being investigated. In this paper, CRMs with 1% cement content, called bitumen-stabilized materials with bitumen emulsion (BSM-Es), were examined. Mixtures that were differentiated in terms of Reclaimed Asphalt Pavement (RAP) content, as well as the amount and type of bitumen emulsions, were subjected to indirect tensile stiffness modulus (ITSM) tests at 5 °C, 13 °C, and 20 °C. The thermal sensitivities of the BSM-E mixtures were analyzed. BSM-E mixture stiffness modulus levels at various temperatures were determined using a statistical approach. On the basis of the results obtained, a discussion on the mechanistic-empirical design of flexible pavements with BSM-E base layers is presented. The potential benefits of using BSM-E materials in road construction in certain aspects of pavement life are indicated.
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Ningtyas, Nurul Fauziah Endah, and Samun Haris. "Analisis Tebal Lapis Perkerasan Jalan dengan Meninjau Sifat Fisik Agregat Lapis Fondasi Bawah pada Ruas Jalan Sofi-Wayabula Pulau Morotai. (Hal. 97-107)." RekaRacana: Jurnal Teknil Sipil 5, no. 3 (September 26, 2019): 97. http://dx.doi.org/10.26760/rekaracana.v5i3.97.
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ABSTRAKJalan sebagai sarana penunjang transportasi darat memiliki peran penting untuk memenuhi kebutuhan manusia. Salah satu material penting dalam pembuatan jalan adalah agregat. Sifat fisik agregat menjadi salah satu faktor penentu tebal lapisan struktur perkerasan. Ruas jalan Sofi–Wayabula adalah ruas jalan nasional strategis di Pulau Morotai dengan menggunakan perkerasan lentur. Agregat yang digunakan untuk lapis fondasi bawah pada ruas jalan ini adalah kombinasi agregat Eks. Palu dengan agregat Eks. Morotai. Tujuan dari penelitian ini adalah untuk menganalisis tebal lapis fondasi bawah berdasarkan koefisien kekuatan relatif ( ) yang didapat dari nilai CBR kombinasi agregat Eks. Palu dengan agregat Eks. Morotai dan agregat Eks. Palu pada struktur perkerasan lentur. Dari hasil perhitungan metode Manual Perkerasan Jalan 2017 didapatkan tebal lapis fondasi bawah sebesar 15 cm, bernilai sama, baik menggunakan kombinasi agregat Eks. Palu dengan agregat Eks. Morotai, maupun agregat Eks. Palu. Sedangkan, dengan menggunakan Pedoman Perkerasan Jalan Lentur 2011 didapat tebal lapis fondasi bawah sebesar 15,054 cm untuk kombinasi agregat Eks. Palu dengan agregat Eks. Morotai dan 14,608 cm untuk agregat Eks. Palu.Kata Kunci: perkerasan lentur, koefisien kekuatan relatif, lapis fondasi bawah. ABSTRACTRoads as a means of supporting land transportation have an important role to meet human needs. One of important material in road construction is aggregate. The aggregate physical properties become one of the determinants of the pavement thickness structure layer. The road segment of Sofi-Wayabula is a strategic national road in Morotai Island by using flexible pavement. The aggregate used for the sub-base course of the road is combination of aggregate Ex. Palu with Ex. Morotai aggregate. The purpose of this research is to analyze the thickness of the sub-base course based on relative strength coefficient (a3) obtained from the value of CBR combination of aggregate Ex. Palu with Ex. Morotai aggregate and aggregate Ex. Palu on flexible pavement structures. From the calculation results of the Pavement Road Manual method 2017, the thick of sub-base course is 15 cm, have equal value using the combination of Ex. Palu aggregate with Ex. Morotai aggregate or the Ex.Palu aggregate. Meanwhile, by using Flexible Road Pavement Guideline 2011 the thickness of the sub-base course is 15,054 cm for combination of Ex.Palu aggregate with Ex. Morotai aggregate and 14,608 cm for Ex.Palu.Keywords: flexible pavement, relative strength coefficient, sub-base course.