Статті в журналах: "Impact compaction"

1

Iwański, Marek, Anna Chomicz-Kowalska, Piotr Ramiączek, Krzysztof Maciejewski, and Mateusz Iwański. "The influence of laboratory compaction methods on the physical and mechanical properties of foamed bitumen recycled mixes." Budownictwo i Architektura 13, no. 1 (March 11, 2014): 053–62. http://dx.doi.org/10.35784/bud-arch.1924.

Повний текст джерела

Анотація:

This study attempts to evaluate the influence of two advisable methods for compacting laboratory specimens of road base recycled mixes with foamed bitumen (MCAS) and bitumen emulsion (MCE). The obligatory regulations for this technology permit fabrication of the specimens using either an impact Marshall compactor or a static hydraulic press. The research showed that the compaction method influenced both the physical and mechanical properties of samples regardless of the type of bitumen binder. What is more, the structure of the material changed after the impact compaction process, which manifested in fact that many of the aggregate particles were crushed in its course. Better strength and resistance to moisture damage was observed in samples prepared in the hydraulic press. This was associated with lower void contents obtained in this compaction method.

Стилі APA, Harvard, Vancouver, ISO та ін.

2

Santhana Krishnan, R., and Sudha Sindhuja Nayani. "Study of heat generation and dissipation mechanism for an exciter shaft and its impact." Journal of Physics: Conference Series 2054, no. 1 (October 1, 2021): 012084. http://dx.doi.org/10.1088/1742-6596/2054/1/012084.

Повний текст джерела

Анотація:

Abstract Compactor is a heavy-duty machinery that uses compaction to reduce the size of waste materials or biomass or compaction of load. A bearing is a machine element that restricts relative motion to only the desired motion, and decreases friction between moving parts. It is an essential component in a compactor and is used for supporting the exciter shaft. Compaction is achieved by vibration of roller drum, which in turn is achieved by means of generated at the exciter shaft with an eccentric mass. During this process of generation of forced excitation, heat is generated at shaft to bearing interface. The current heat generation and dissipation paths for the bearing on the exciter shaft of the compactor were studied and calculated. Suggestions for heat dissipation optimization are provided. Various optimization methods were devised for heat dissipation to improve the wear as well as efficiency of the bearing and further testing is required for implementation of same.

Стилі APA, Harvard, Vancouver, ISO та ін.

3

Jiang, Chunlin, Yanhui Ge, Baoqun Wang, Luchen Zhang, and Youbo Liu. "Impact of the High-Energy Dynamic Compaction by Multiple Compactors on the Surrounding Environment." Advances in Civil Engineering 2021 (November 29, 2021): 1–19. http://dx.doi.org/10.1155/2021/6643064.

Повний текст джерела

Анотація:

Dynamic compaction machine (DCM) is a widely adopted ground reinforcement technology. However, dynamic compaction energy has a very significant impact on the surrounding environment. At present, the research on the impact of dynamic compaction mainly focuses on the effect of the tamping behavior of a single compactor in the working state, whereas the research on the impact of multiple compactors working jointly is rare. To study the impact of the dynamic compaction energy of multiple compactors working jointly on the surrounding environment, the dynamic response model for multiple compactors working in the same field was established based on the explicit dynamic analysis module in ABAQUS. The validity of the model was verified by comparison with the measured data. Based on this, the impact of the dynamic compaction energy of multiple compactors with different working conditions in terms of the arrangement, spacing, and working time interval was analyzed. The results showed that the arrangement and spacing of the compactors had a remarkable influence on the distribution of the dynamic compaction energy in the surrounding environment. Under the condition of multiple compactors working with a time interval of less than 10 s, the impact of the superimposed dynamic compaction energy due to the interaction of multiple compactors had to be considered.

Стилі APA, Harvard, Vancouver, ISO та ін.

4

Gui, Meenwah, Truc Phan, and Thang Pham. "Impacts of Compaction Load and Procedure on Stress-Deformation Behaviors of a Soil Geosynthetic Composite (SGC) Mass—A Case Study." Applied Sciences 10, no. 18 (September 11, 2020): 6339. http://dx.doi.org/10.3390/app10186339.

Повний текст джерела

Анотація:

Fill compaction in the construction of Geosynthetic Reinforced Soil (GRS) mass is typically performed by operating a vibratory or roller compactor, which in turns imposed a compaction load in direction perpendicular to the wall face. The compaction process resulted in the development of the so-called compaction-induced stress (CIS), which may subsequently increase the stiffness and strength of the fill material. Compaction process is normally simulated using one of the following compaction procedures—(i) a uniformly distributed load acting on the top surface of each soil lift, (ii) a uniformly distributed load acting on the top and bottom surface of each soil lift, and (iii) a moving strip load with different width. Uncertainties such as compaction procedures, compaction and surcharge loads led to the disparity in studying the mechanism of GRS mass. This paper aimed to study the impact of compaction load, compaction procedure, surcharge load and CIS on the stress-deformation behavior of GRS mass via the simulation of a 2 m high Soil Geosynthetic Composite (SGC) mass and a 6 m high GRS mass. The results were examined in terms of reinforcement strains, wall lateral displacements, and net CIS. Results from the analysis show the important impacts of compaction conditions on the stress-deformation behavior of SGC mass and the CIS.

Стилі APA, Harvard, Vancouver, ISO та ін.

5

Hata, Shojiro, and Kazuyoshi Tateyama. "Relationship between vibratory roller compaction and indoor impact compaction test." Journal of Terramechanics 24, no. 1 (January 1987): 119–20. http://dx.doi.org/10.1016/0022-4898(87)90091-7.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

6

Zhang, Kai, Zhan Yong Yao, Qing Sen Shang, and Xiu Guang Song. "Research of Impact Compaction Technology on Foundation and Subgrade in Yellow River Flooded Area." Advanced Materials Research 368-373 (October 2011): 1142–47. http://dx.doi.org/10.4028/www.scientific.net/amr.368-373.1142.

Повний текст джерела

Анотація:

To study the feasibility of impact compaction on the foundation and subgrade compaction in Yellow River flooded area and explore construction process and control parameters that could ensure good compaction results, experiment was conduct on impact compaction. By way of detecting the influence of impact compaction on settlement, moisture content and degree of compaction in different construction technology to analysis the feasibility of impact compaction on the foundation and subgrade compaction in Yellow River flooded area. By evaluating the effect of compaction of different construction techniques, appropriate construction technology and control parameters of impact compaction on foundation and subgrade in the Yellow River flooded area was summarized. Research results showed that impact compaction had a good compaction effect on foundation and subgrade in Yellow River flooded area. For foundation compaction, discontinuous impaction construction should be adopted and control parameters should use degree of compaction and settlement and the best impaction times should be 12 -14 times. For subgrade compaction, the thickness of the loose layer should be 80cm and the best impaction times should be 25-30 times.

Стилі APA, Harvard, Vancouver, ISO та ін.

7

Niroumand, Bahman, and Hamed Niroumand. "Gravel impact compaction piers as a method of soil improvement." Revista de la construcción 21, no. 3 (2022): 539–54. http://dx.doi.org/10.7764/rdlc.21.3.539.

Повний текст джерела

Анотація:

The purpose of this study was to evaluate the performance of gravel impact compaction piers system (GICPs) in improving a 3.5m thick loose silty sand in a multilayer coastal soil system located in Bushehr, Iran. The liquefiable sandy soil layer was layered on clay layers with moderate to very stiff consistency and below the engineering embankment layer with a thickness of 1.8 m. Implementation of gravel impact compaction piers is a new generation of aggregate piers. Gravel impact compaction piers were used to improve the liquefiable soil layers and to increase the bearing capacity and reduce subgrade settlement to withstand surface infrastructures. The process of making gravel impact compaction piers in a triangular or square-patterned grid was created using three types of special mandrels and feeding and compacting the gravels in the cavity in several stages without removing the soil from the cavities. The experience gained in this case study showed that artificial liquefiable was created immediately after the construction of these piers in a limited area and the soil became unstable. After about 11-14 days, the soil stabilized rapidly. The results of the standard penetration test in the matrix soil around the piers showed that the amount of (N1)60 in compacted soils was in the range of 21-30 and on average 15 times the amount of (1-3) in the initial soil. Also, the relative density of the initial soil was increased from 25% to 75% after soil improvement. Accordingly, by relying merely on the compaction properties of the piers and without relying on other primary soil remediation factors, such as piers drainage and soil texture change, the safety factor of the improved soil is 1.7-1.95 times the minimum required according to the two risk levels in the design.

Стилі APA, Harvard, Vancouver, ISO та ін.

8

Yuan, Yu Qing, Xuan Cang Wang, and Hui Jun Shao. "Study on Impact Compaction of Aeolian Sand Subgrade and its Effect Evaluation." Advanced Materials Research 378-379 (October 2011): 370–73. http://dx.doi.org/10.4028/www.scientific.net/amr.378-379.370.

Повний текст джерела

Анотація:

In order to solve the problem of aeolian sand subgrade compaction, we studied the technology of impact compaction, applied it to the engineering practice and analyzed its effect with Rayleigh wave. The technology of impact compaction can combine the compaction of potential energy and kinetic energy and make it easier for the materials to reach their elastic stage. With the combined function of "knead-roll-impact", the impact compaction road roller can compact the soil body and offer 6～10 times impact force and 3～4 times the depth of influence more than the vibratory roller. The impact compaction methods of aeolian sand subgrade were put forward. The comparative field compaction tests between impact and vibratory compaction are carried through, which are detected by Rayleigh wave. The results show that the impact compaction can make the density of the aeolian sand subgrade 2～5% higher than the vibratory compaction, and reach the influence depth of 7 metres. To sum up, the impact compaction can clearly increases the strength and stiffness of aeolian sand subgrade with a dynamic elastic modulus of 202.63MPa.

Стилі APA, Harvard, Vancouver, ISO та ін.

9

Wu, J. Y., and J. X. Wang. "The Application of Impact Tester for Compaction Control." Applied Mechanics and Materials 501-504 (January 2014): 254–57. http://dx.doi.org/10.4028/www.scientific.net/amm.501-504.254.

Повний текст джерела

Анотація:

The safety of the earth structures is highly dependent upon the fill compaction quality. Recently developed nondestructive testing techniques (NDT) present many advantages in comparison with conventional field density measurements. Therefore, use of NDT in monitoring of the fill quality appears to be attractive for future pavement geotechnics applications. This paper presents an alternative technology using non-destructive Clegg impact tester for compaction control in silty sand. 132 compaction tests and impact tests with varying values of compaction effort, moisture content, and density were conducted in laboratory. Each observed impact value (Iv) was then considered as a function of its corresponding compaction effort, moisture content and dry density. Results of the study show that for the silty sand tested, the variations of Iv with moisture content are similar to the corresponding unique moisture-density compaction relationship. The values of Iv generally correlate well with moisture-density relationship for each compaction effort. Along with a speedy moisture tester, dry density can be predicted using target Iv values in a fast and efficient manner based on current standard specification.

Стилі APA, Harvard, Vancouver, ISO та ін.

10

Yuan, Yu Qing, Wei Li, Tian Wen Yang, and Tao Guo. "Impact Compaction Technology of Filling Subgrade with Yellow River Sandy Soil." Applied Mechanics and Materials 193-194 (August 2012): 717–20. http://dx.doi.org/10.4028/www.scientific.net/amm.193-194.717.

Повний текст джерела

Анотація:

In order to reduce sinking after subgrade construction, impact compaction technology was put forward. The engineering characteristics of Yellow River sandy soil located in Kaifeng, and impact compaction technologies were analyzed. The contrast tests were also carried through, including vibration compaction and impact one. The results show that the subgrade can obtain higher compaction degree with impact compaction technology than the other method, with 2%-5% increasing.

Стилі APA, Harvard, Vancouver, ISO та ін.

11

Kuang, Xi Long. "Testing Study and Numerical Analysis of Dynamic Compaction on the Red Sandstone Rubble Soil." Applied Mechanics and Materials 97-98 (September 2011): 151–55. http://dx.doi.org/10.4028/www.scientific.net/amm.97-98.151.

Повний текст джерела

Анотація:

The drop distance, times of dynamic compaction and other parameters are studied by on-site testing in order to analyse quantitatively the impact on effective reinforcement depth and radius of the red sandstone rubble soil. Large amounts of on-site test data shows that compactness standard is 93%, strong encryption range is 1.0～4.0m, the effective impact depth is 4～6m and the effective impact radius is 2.5～3.5m. At the same time, through comparison and verification the on-site testing data and numerical analysis, the relationship between times of dynamic compacting and sandstones subside is . Further more, it is revealed that dynamic compaction can restrain effectively the deformation of high fill embankment of the red sandstone rubble soil.

Стилі APA, Harvard, Vancouver, ISO та ін.

12

Song, Rong Fang, and Dai Wang. "Application Study of Impact Compaction Technology in Wetness and Softness Loess Roadbed Treatment." Advanced Materials Research 594-597 (November 2012): 1477–81. http://dx.doi.org/10.4028/www.scientific.net/amr.594-597.1477.

Повний текст джерела

Анотація:

In order to study the applicability and strengthening effect of impact compaction technology in wetness and softness loess roadbed treatment, impact compaction technology was applied in ground treatment and layered filling roadbed compact of a freeway sub-grade construction, and compactness and settlement of the soil were also measured. Test results suggest: impact compaction technology can effectively apply to shallow wetness and softness loess roadbed treatment and the most effective depth is about 80cm, and this effect appears to increase with the impact compaction times and 30 impact compaction times is the most suitable. As regards the layered filling sub-grade, when the loose paving thickness is 40cm, compactness after 40 times compaction can satisfy specified demand. At the same time, combined with the test settlement, the control criterion of impact compaction quality is investigated.

Стилі APA, Harvard, Vancouver, ISO та ін.

13

Widyastuti, Rindang Fajarin, Faizah Ali, Sugiarto Putra Wijaya, Eka Nurul Falah, and Iyando Aditiyawan. "Investigation of the Dwelling Time and Compaction Pressure Effect on Mechanical Properties and Microstructure of the Cu-Sn Composite." Key Engineering Materials 939 (January 25, 2023): 57–62. http://dx.doi.org/10.4028/p-y6pg8i.

Повний текст джерела

Анотація:

Powder metallurgy has become a compatible alternative method in term of manufacturing complex component, such as frangible bullet. A bullet with frangible properties can be manufactured by using copper-based metal matrix composite with tin as the reinforce. During compaction process, the applied load and dwelling time are considered as substantial factor which affect the final product. Therefore, the aim of the present work study is to observe the pressure and the holding time during the compacting process (dwelling time) which has an impact on the mechanical properties of the Cu-Sn composite product. The green component or pressed product is tested with various compaction pressure variables, namely 500, 600, and 700 MPa with 0, 5, 15, 30, 45 minutes dwelling time, respectively. The sintering process is performed at 260°C for 30 minutes in the horizontal furnace. The result shows that the surface contact area was increased along with the compaction load upsurge which led to low porosity green compact. The 700 MPa compaction pressure with 15 minutes dwelling time has the optimum density, hardness, and compressive strength, which had 8,454 gr/cm3, 87 HRF and 349.74 MPa in value. The compacting product has been tested on Scanning Electron Microscope (SEM) and showed that 700 MPa compaction pressure had the best powder densification process.

Стилі APA, Harvard, Vancouver, ISO та ін.

14

Fenton, Gregg, Blaine Asay, and Devon Dalton. "Impact Compaction of a Granular Material." Procedia Engineering 103 (2015): 121–28. http://dx.doi.org/10.1016/j.proeng.2015.04.017.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

15

Kulig, Ryszard, Grzegorz Łysiak, Zbigniew Krzysiak, Monika Wójcik, and Renata Różyło. "Impact of Pressure on the Parameters of Pea Straw Compaction." Agricultural Engineering 23, no. 3 (September 1, 2019): 79–87. http://dx.doi.org/10.1515/agriceng-2019-0028.

Повний текст джерела

Анотація:

AbstractThis paper presents the results of pea straw compaction efficiency tests. The compliance of the tested material to pressure agglomeration was assessed depending on the compaction pressure used (45-113 MPa). The compaction was carried out using a Zwick testing machine, type Z020/TN2S, and a closed die pressing unit. It was found that, along with the pressure increase, the material density in the chamber increased (from 1.255 to 1.76 g∙cm−3), as well as the agglomerate's density (from 0.739 to 1.05 g∙cm−3) and the product's mechanical resistance (from 0.31 to 0.69 MPa). Increasing the compaction pressure in the analyzed range increased the unit value of compaction work, from 17.16 to 34.27 J·g−1.

Стилі APA, Harvard, Vancouver, ISO та ін.

16

Ta, Dzung Quoc, Al-Harthy, M., Hunt, S, and Sayers, J. "THE IMPACT OF UNCERTAINTY ON SUBSIDENCE AND COMPACTION PREDICTION." Science and Technology Development Journal 12, no. 6 (March 28, 2009): 84–95. http://dx.doi.org/10.32508/stdj.v12i6.2257.

Повний текст джерела

Анотація:

This paper presents the stochastic approach using Monte Carlo simulation as applied to compaction and subsidence estimation in an offshore oil and gas deep-water field in the Gulf of Mexico. The results reveal both the impact of using probability distributions to estimate compaction and subsidence for a disk shaped-homogenous reservoir as well as taking into account Young's modulus, Poisson's ratio and the reduction of pore fluid pressure. The uncertainty reservoir model is also compared with numerical simulation commercial software - Eclipse 300. The stochastic-based simulation results confirm that the deterministic results obtained from the coupled geomechanical - fluid flow model are in the range of acceptable distribution for stochastic simulation. The sensitive analysis shown that Young's modulus has more impact on compaction than Poisson's ratio. The results also presented that values of Young's modulus in this deep-water field in Gulf of Mexico lying beyond 140,000psi are insignificant to compaction and subsidence. Based on output results of compaction and subsidence with the stochastic model, potential reservoirs presenting subsidence and compaction are described as an uncertainty range within distribution of Young's modulus, Poisson's ratio and the reduction of pore fluid pressure in large-scale regional model.

Стилі APA, Harvard, Vancouver, ISO та ін.

17

Zhang, De, Zhiqiang Cheng, Dajiang Geng, Shengjia Xie, and Tao Wang. "Experimental and Numerical Analysis on Mesoscale Mechanical Behavior of Coarse Aggregates in the Asphalt Mixture during Gyratory Compaction." Processes 10, no. 1 (December 27, 2021): 47. http://dx.doi.org/10.3390/pr10010047.

Повний текст джерела

Анотація:

Compaction is a critical step in asphalt pavement construction. The objective of this study is to analyze the mesoscale mechanical behaviors of coarse aggregates in asphalt mixtures during gyratory compaction through experiments and numerical simulation using the Discrete Element Method (DEM). A novel granular sensor (SmartRock) was embedded in an asphalt mixture specimen to collect compaction response data, including acceleration, stress, rotation angle and temperature. Moreover, the irregularly shaped coarse aggregates were regenerated in the DEM model, and numerical simulations were conducted to analyze the evolution of aggregate interaction characteristics. The findings are as follows: (1) the measured contact stress between particles changes periodically during gyratory compaction, and the amplitude of stress tends to be stable with the increase of compaction cycles; (2) the contact stress of particles is influenced by the shape of aggregates: flat-shaped particles are subjected to greater stress than angular, fractured or elongated particles; (3) the proportion of strong contacts among particles is high in the initial gyratory compaction stage, then decreases as the number of gyratory compactions grows, the contacts among particles tending to homogenize; (4) during initial gyratory compactions, the normal contact forces form a vertical distribution due to the aggregates’ gravity accumulation. The isotropic distribution of contact forces increases locally in the loading direction along the axis with a calibrated internal angle orientation (1.25°) in the earlier cyclic loading stage, then the local strong contacts decrease in the later stage, while the strength of the force chains in other directions increase. The anisotropy of aggregate contact force networks tends to weaken. In other words, kneading and shearing action during gyratory compaction have a positive impact on the homogenization and isotropy of asphalt mixture contact forces.

Стилі APA, Harvard, Vancouver, ISO та ін.

18

Uhlíř, V., J. Mareček, and J. Červinka. "Impact of soil compaction in sowing on development and crops of sugar beet." Research in Agricultural Engineering 52, No. 1 (February 7, 2012): 11–16. http://dx.doi.org/10.17221/4874-rae.

Повний текст джерела

Анотація:

Putting together work operations minimizes the number of machine passes across the plot, which helps to reduce negative soil compaction and to save fuels. However, the combination of working operations also reflects in the increased weight of machines, which – on the other hand – can result exactly in soil compaction. This is why the potential adverse phenomenon can be compensated by using tyres with a larger contact surface with the base. In the case of sowing root crops, some problems may appear with the application of these tyres as a certain part of the stand has been sown in their track. The paper brings an assessment of the possibility to use twin assembly tyres on the tractor model Fendt 822 and on the sowing drill model Monosem NG plus with 18 drilling mechanisms. Parameters to be assessed were soil compaction, and the development of plants sown inside and outside the tractor track. Although the degree of soil compaction was higher in the tractor track, the biological characteristic of plants including yield reached more favourable criteria of assessment. The situation paradoxically resulted from the creation of more favourable moisture conditions in the soil.

Стилі APA, Harvard, Vancouver, ISO та ін.

19

Sano, Yukio, Kiyohiro Miyagi, and Peter Arathoon. "Nonunique Dynamic Equilibrium Constitutive Relation of Metal Powder Depending on its Microstructure." Journal of Engineering Materials and Technology 118, no. 1 (January 1, 1996): 12–18. http://dx.doi.org/10.1115/1.2805926.

Повний текст джерела

Анотація:

It was observed in an earlier work by Morimoto et al. [Inst. Phys. Conf. Ser. No. 70, Oxford 1984, p. 427] that the dynamic compact of an aluminium powder medium had greater flakiness and contiguity ratio than the static compact of the same density. This observed difference in micro structure is used to explain their result that the dynamic pressure of the medium is higher than the static pressure for a given density: the degree of rotation of particles during compaction is assumed to decrease for higher strain rates, because of the shorter time available, causing an increase in plastic particle deformation in the compaction direction, and increased resistance to the compaction. The normal Hugoniot equation derived, in which the mean strain rate averaged over a single steady wavefront is introduced, indicates that a rise of the normal Hugoniot with an increase in the strain rate results macroscopically from the increase in the propagation velocity of the wavefront. The multiwave Hugoniot equation is found to depend on the strain rate history of a given material. In compactions of a metal powder medium by punch impact, the wavefronts passing through the medium are approximately steady if the punch mass is sufficiently larger than the medium mass. But both the number of wavefronts arising during the compaction and the amplitudes of the strain waves, and hence the strain rate histories, vary with compaction conditions such as punch mass and initial punch velocity. This implies that a dynamic equilibrium constitutive relation for the medium will depend on the compaction conditions, and therefore cannot be determined uniquely for any two compactions.

Стилі APA, Harvard, Vancouver, ISO та ін.

20

Xiao, Cong, Yuzhu Chen, Teng Ma, and Wen Xiong. "Impact of Pressure on Arsenic Released from Pore Water in Clayey Sediment." Toxics 10, no. 12 (November 29, 2022): 738. http://dx.doi.org/10.3390/toxics10120738.

Повний текст джерела

Анотація:

Overpumping can cause arsenic to be released from the pore water in clayey aquitards into aquifers. The amount of water pumped during groundwater exploitation may change over time, leading to different soil-compaction rates or patterns. However, the impact of pressure on the release of arsenic during the compaction of a clayey aquitard is poorly understood. We performed a laboratory-compaction experiment using clayey sediment to identify the effects of compaction rates and patterns on arsenic release by analyzing the chemical characteristics and arsenic species present in pore water samples collected at different stages of the compaction experiment. A rapid (PV increased linearly) and a slow (PV increased exponentially) water-release patterns were recognized according to the compaction rate. We observed that arsenic concentrations in the slow pattern (6.7 to 36.4 μg/L) were considerably higher than those in the rapid pattern (7.6 to 16.1 μg/L). Furthermore, concentrations were the highest in the accelerated compaction pattern (16.8 to 47.4 μg/L), followed by those in the constant and decelerated patterns (4.3 to 14.4 μg/L). Overall, compaction rate and pattern did not alter the arsenic-release mechanism; however, they did alter the moisture content of the sediment at each stage, which indirectly led to differences in the released arsenic concentrations. These results suggest that pumping rates and patterns must be considered to prevent arsenic contamination in groundwater-extraction scenarios.

Стилі APA, Harvard, Vancouver, ISO та ін.

21

Sano, Yukio. "Multiple Shock Compaction of Simple Type Powders by Punch Impact." Journal of Energy Resources Technology 114, no. 2 (June 1, 1992): 117–38. http://dx.doi.org/10.1115/1.2905931.

Повний текст джерела

Анотація:

Recently, we have elucidated some mechanical behaviors of powders during the compaction. The elucidation involves the constitutive relations of a powder medium under the multishock compaction, the qualitative behavior such as the similarities of the compaction processes, the die wall friction effect, and the uniformity of the final density distribution of the compact with a high density, and the quantitative behavior analyzed by the pseudo-viscosity method and the shock fitting. This review describes this behavior systematically.

Стилі APA, Harvard, Vancouver, ISO та ін.

22

Jayawickrama, Priyantha W., Aruna L. Amarasiri, and Pedro E. Regino. "Use of Dynamic Cone Penetrometer to Control Compaction of Granular Fill." Transportation Research Record: Journal of the Transportation Research Board 1736, no. 1 (January 2000): 71–80. http://dx.doi.org/10.3141/1736-10.

Повний текст джерела

Анотація:

Granular material is commonly used as backfill and embedment material for buried structures, including thermoplastic pipe. Proper compaction of this material is crucial to the successful performance of the pipe. However, the commonly used Proctor density approach cannot be used for the field compaction control of these materials because it does not provide a well-defined moisture-density relationship. An alternative method used by the authors for compaction control of such materials is described. This method involves a device known as the dynamic cone penetrometer (DCP). Findings are presented from a series of DCP tests conducted on a range of granular backfill materials that belong to ASTM D 2321 Classes I and II. These materials were compacted using ( a) an impact rammer and ( b) a vibratory plate compactor. The level of compaction energy was varied by changing the number of passes. The data obtained from these tests are presented in the form of DCP blow count profiles, which are then used as the basis for comparison between different materials, compaction equipment, and levels of compaction energy. A series of full-scale load tests conducted on high-density polyethylene (HDPE) pipe installations is also described. An overview is provided of how the DCP data may be combined with load-deflection data from full-scale load tests to establish guidelines for compaction control of pipe backfill.

Стилі APA, Harvard, Vancouver, ISO та ін.

23

Cai, Zhongbing, and Chengchun Qiu. "The Bearing and Breakage Characteristics of Crushed Stone Aggregates in the Bedding Course of Permeable Roads." Advances in Civil Engineering 2020 (October 28, 2020): 1–9. http://dx.doi.org/10.1155/2020/8890672.

Повний текст джерела

Анотація:

The current study of permeable roads helps address urban flooding in Chinese cities caused by frequent heavy rainfall and build smart cities with sponge-like functionality. Crushed stone is widely used in constructing the bedding course of permeable roads because it has good water permeability. Experiments on the compaction of crushed stone were carried out by considering the impact of particle size and gradation to examine the strength and particle breakage characteristics of crushed stone and evaluate its use as the aggregate in the bedding course of permeable roads. The compaction process can be divided into two stages, i.e., the preliminary compaction stage and the particle crushing and intensive compaction stage. The latter consists of an alternating cycle of compacting and crushing. The particle size distribution after crushing can be described analogously to the Talbot continuous gradation equation. Single particle size samples are subject to earlier and stronger particle breakage than the mixed particle size sample, which are affected by both compaction level and loading speed. This study has important application value, and it provides experimental support for the study of materials for urban permeable roads.

Стилі APA, Harvard, Vancouver, ISO та ін.

24

Pohořalý, J., R. Klvač, T. Kent, M. Kleibl, E. Coates, and B. Horgan. "Impact of forest biomass for energy harvesting on soil compaction – Irish case study." Journal of Forest Science 60, No. 12 (November 27, 2014): 526–33. http://dx.doi.org/10.17221/89/2014-jfs.

Повний текст джерела

Анотація:

An assessment of soil compaction caused by machinery used in stump and/or logging residue extraction for energy on soils typical of Ireland. We determined unaffected soil conditions and to find the compaction grade after timber harvesting and bundling activities, and to compare those results with stands where timber harvesting was followed by stump extraction for energy. The investigation was carried out in Ireland on three different locations which had a slightly different proportion of stones in their soils. Two of the soils were purely mineral soils, and the third was a mineral soil affected by anthropogenic activities. To ensure comparable results as much as possible, the moisture content of the soil on wet basis was investigated. Each location was purposely treated. Therefore, on each location plots were identified as follows: plots unaffected by operation (reference area), plots after timber harvesting, plots after timber harvesting and bundling operation, and plots after timber harvesting and stump extraction operation. According to the experimental design 40 repetitions on each of the three different treatments were set. The results showed that the compaction of soil occurred on plots after timber harvesting, but there was not a significant difference between compaction grades with and without logging residue bundling operation. However, once the site was extracted of stumps, the soil became too loose and no significant difference was found compared to unaffected soil.  

Стилі APA, Harvard, Vancouver, ISO та ін.

25

Czech, Krzysztof R., and Wojciech Gosk. "Impact of the Operation of a Tri-band Hydraulic Compactor on the Technical Condition of a Residential Building." Applied Sciences 9, no. 2 (January 18, 2019): 336. http://dx.doi.org/10.3390/app9020336.

Повний текст джерела

Анотація:

The study investigates the surface vibrations generated by a new generation, tri-band hydraulic compactor type V8 from Maschinentechnik Schrode AG (MTS), and a reversible plate compactor type DPU 6055 from Wacker Neuson in close proximity to a low-rise residential building. Compaction works were carried out in three stages, at distances: 15 m, 10 m, and 5 m from the building, and at three depths: 0.4 m, 1.2 m, and 1.8–2.0 m. The research was conducted at one measurement point, located on the outer foundation wall of the building, and at three measurement points located on the ground at distances of 1.25–7.5 m from the building. The study analyses the distribution of peak component particle accelerations at the ground, and peak component particle velocities at the foundation wall of the building as a function of the distance of compactors from the building and the depth of compaction works, as well as the mode of work of hydraulic compactor type V8 from MTS. The study contains the comparison of the permissible vibration levels that are recommended by selected European standards (DIN, BS, VSS, and PL) and an approximate assessment of the impact of vibrations on the technical condition of the residential building.

Стилі APA, Harvard, Vancouver, ISO та ін.

26

Lukashevich, Viktor, Igor Efanov, Viktor Vlasov, and Olga Lukashevich. "Asphalt concrete pavement reinforced with chemical fibers." MATEC Web of Conferences 216 (2018): 01013. http://dx.doi.org/10.1051/matecconf/201821601013.

Повний текст джерела

Анотація:

Asphalt concrete pavement which is currently built in accordance with the existing requirements does not withstand the standard service life. Various kinds of damages occur. Fiber reinforcement of asphalt concretes is one of the effective means to deal with deformations and fractures of road pavements, such as rutting, buckling, crack formation and shear. Chemical fibers serving as reinforcement are of great concern herein. The major purpose of this work was evaluation of reinforcement fibers resistance to natural environment and climatic impacts within the conditions of experimental production construction and studying compactibility of asphalt concrete mixture with fiber reinforcement. Infrared spectroscopy and physical-chemical investigations of fibers were used to study changing properties of fiber-forming polymer. Compactibility of asphalt concrete mixture with fiber reinforcement was determined upon compaction factor. Research results revealed insignificant influence of natural environment and climatic impacts on the properties of fiber reinforcement material. In order to obtain the standard compaction factor of asphalt concrete additional compacting impact is not required.

Стилі APA, Harvard, Vancouver, ISO та ін.

27

Chukharev, R. A., N. E. Tarasova, and E. K. Chabutkin. "SIMULATION OF IMPACT PROCESS OF SOIL COMPACTION." Russian Automobile and Highway Industry Journal 17, no. 2 (May 25, 2020): 208–18. http://dx.doi.org/10.26518/2071-7296-2020-17-2-208-218.

Повний текст джерела

Анотація:

Introduction. During the construction of modern highways, much attention is paid to compaction of bases consisting of natural soils. They require the use of special equipment, including self-propelled machines, performing compaction in a continuous cycle. But when designing it, certain difficulties arise in determining the parameters of impact accelerators and the mass of the impact plate. The purpose of the work is to study the influence of the parameters of working equipment on the process of soil deformation.Materials and methods. To check the influence of the parameters of the tamper equipment on the compaction process, a method of mathematical modeling of the process using rheological models was chosen. The working cycle of impact ramming is divided into four phases. A mathematical description of the movement of the stamp and soil in each of the phases of movement is given. The change in the stress condition in time in the body of the soil half-space is considered.Results.Тhe time dependence of the soil stress condition was obtained for different stiffnesses of the spring impact accelerator and the change in the stamp mass. A joint analysis of the obtained dependencies showed that when designing impact equipment intended for compaction of naturally occurring soils, it requires matching the peak stresses from the mass of the stamp and the stiffness of the impact accelerators. This will make it possible to stretch the action of stresses in time, to form a compacted core in the soil half-space quickly and require a smaller number of strokes on one track to obtain the required material density.Discussion and conclusion. The proposed model of tamper equipment made it possible to consider the processes occurring in the soil half-space, to obtain comparative characteristics of the stamp mass and the rigidity of impact accelerators. The obtained data correlate well with the data of other authors. The results of the study may be useful to engineers involved in the development of new techniques of intensifying action.Financial transparency: the authors have no financial interest in the presented materials or methods. There is no conflict of interest.

Стилі APA, Harvard, Vancouver, ISO та ін.

28

Mileusnić, Zoran I., Elmira Saljnikov, Rade L. Radojević, and Dragan V. Petrović. "Soil compaction due to agricultural machinery impact." Journal of Terramechanics 100 (April 2022): 51–60. http://dx.doi.org/10.1016/j.jterra.2021.12.002.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

29

Gao, You Shan, Zhi Song, Ai Hong Wang, and Ze Kun Jin. "Dynamic Simulation for Rolling Impact Compaction Machine." Advanced Materials Research 430-432 (January 2012): 1610–13. http://dx.doi.org/10.4028/www.scientific.net/amr.430-432.1610.

Повний текст джерела

Анотація:

Through established the simulation model for the engine and the traction host powertrain of rolling impact compaction machine, Simulated the working load with time history with the simulation parameters of rolling impact compaction machine. The simulation accuracy was verified by compared between the test speed and the simulation speed. The speed, turbine torque, torque converter efficiency, torque converter, gear ratios, fuel consumption, engine power, torque are dynamic changes follow with the alternating load and slope load so as to adapt to the dynamic drag torque fluctuations. Traction host power must be equipped with a full host transmission of the internal combustion engine. Driveline should be hydraulic transmission fluid or hydraulic machinery.

Стилі APA, Harvard, Vancouver, ISO та ін.

30

Nawaz, Muhammad Farrakh, Guilhem Bourrié, and Fabienne Trolard. "Soil compaction impact and modelling. A review." Agronomy for Sustainable Development 33, no. 2 (January 31, 2012): 291–309. http://dx.doi.org/10.1007/s13593-011-0071-8.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

31

Ivanov, R. A., and A. I. Fedulov. "Description of process of impact soil, compaction." Journal of Mining Science 35, no. 2 (April 1999): 146–49. http://dx.doi.org/10.1007/bf02565368.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

32

Kleibl, Miroslav, Radomír Klvač, and Josef Pohořalý. "Impact of Forest Operation on Soil Compaction – San Rossore Case Study." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 63, no. 4 (2015): 1133–40. http://dx.doi.org/10.11118/actaun201563041133.

Повний текст джерела

Анотація:

The paper presents the assessment of compaction grade caused by machinery used in forest biomass for energy harvesting. The main aim was to determinate unaffected soil conditions, the compaction grade exactly after harvesting activities, the return of soil after couple of years and compaction grade in stands, which were not harvested but affected by skidding and seed collection activities. Therefore four different compaction grades were evaluated. To ensure as much as possible uniform soil conditions also soil samples were evaluated. Soil samples were collected using Kopecky physical metal rings and followed characteristics of soil were determined i.e. moisture content, bulk density and porosity, respectively. In San Rossore national park 24 plots were identified of which 8 were harvested in 2011 year (H2011), 8 were harvested in 2005 year (H2005), 7 were not harvested but were affected by other activities (NH) and 1 was unaffected (U). On each plot 50 repetition of measurement were carried out. The results display both: significantly different compaction grade of soil and return of the soil towards the original conditions after 6 years.

Стилі APA, Harvard, Vancouver, ISO та ін.

33

Olekšáková, Denisa, Peter Kollár, Miroslav Neslušan, Miloš Jakubčin, Ján Füzer, Radovan Bureš, and Mária Fáberová. "Impact of the Surface Irregularities of NiFeMo Compacted Powder Particles on Irreversible Magnetization Processes." Materials 15, no. 24 (December 14, 2022): 8937. http://dx.doi.org/10.3390/ma15248937.

Повний текст джерела

Анотація:

One specific group of materials with excellent application potential are powder-compacted soft magnetic materials. These materials have been intensively studied by materials scientists to improve their magnetic properties. This work describes the influence of mechanical smoothing applied to Ni80Fe15Mo5 (wt.%) alloy particle surfaces before the process of compaction. The soft magnetic properties of compacted powders prepared from smoothed and non-smoothed particles were investigated using the following measurements: coercive field, permeability, excess loss, and Barkhausen noise analysis. We found that compactions prepared with smoothed powder particles exhibit a lower value of coercivity (4.80 A/m), higher initial (10,850) and maximum relative permeability (27,700), and low-frequency core losses (1.54 J/m3) in comparison with compactions prepared with non-smoothed particles.

Стилі APA, Harvard, Vancouver, ISO та ін.

34

Baer, M. R. "Numerical Studies of Dynamic Compaction of Inert and Energetic Granular Materials." Journal of Applied Mechanics 55, no. 1 (March 1, 1988): 36–43. http://dx.doi.org/10.1115/1.3173658.

Повний текст джерела

Анотація:

In this paper a numerical study of dynamic compaction of granular materials is presented. A multiphase mixture model treating two-phase nonequilibrium flow is applied to describe dynamic compaction experiments. Compaction is modeled using a description of grain distortion driven by pressure differences. Various energetic and inert granular materials including HMX, Fluid A (Nitrocellulose), Melamine, and Teflon are studied for various piston-impact conditions and compared to existing data. Numerical analysis of a ramp-wave piston-impact experiment is also examined. The multiphase mixture model predicts reasonably well the observed steady compaction wave characteristics. Dynamic compaction experiments with detailed resolution are needed to better address the transient behavior of compaction waves in granular materials.

Стилі APA, Harvard, Vancouver, ISO та ін.

35

Nurek, Tomasz, Arkadiusz Gendek, Kamil Roman, and Magdalena Dąbrowska. "The Impact of Fractional Composition on the Mechanical Properties of Agglomerated Logging Residues." Sustainability 12, no. 15 (July 29, 2020): 6120. http://dx.doi.org/10.3390/su12156120.

Повний текст джерела

Анотація:

Fractional composition, as well as the temperature of the agglomeration process, affect the quality and mechanical properties of briquettes. In this research, shredded forest logging residues were investigated. Compaction tests were carried out for several specially prepared mixtures made of shares of fractions with different particle sizes. The moisture content, density of briquettes, specific work of compaction, mechanical durability, and biomass susceptibility to compaction were analyzed. Studies have confirmed the significant impact of the fractional composition of compacted biomass on its susceptibility to process parameters and the quality of the final product. Statistical analysis confirmed that the density of the briquette, its durability, the specific work of compaction, and the susceptibility of the tested biomass to compaction strongly depend on the particle size of the compacted biomass. An increase in temperature to 73 °C increased specific work by 40% and contributed to the high quality of briquettes in the range from 0.768 to 1.14 g·cm−3.

Стилі APA, Harvard, Vancouver, ISO та ін.

36

Bonicelli, Alessandra, Maurizio Crispino, Filippo Giustozzi, and Melanie Shink. "Laboratory Analysis for Investigating the Impact of Compaction on the Properties of Pervious Concrete Mixtures for Road Pavements." Advanced Materials Research 723 (August 2013): 409–19. http://dx.doi.org/10.4028/www.scientific.net/amr.723.409.

Повний текст джерела

Анотація:

Pervious concrete is a relatively new material, standards and rigorous specifications for construction and placement are therefore still missing. One the one hand, the main characteristic to achieve is a high permeability to allow meteoric water percolate in the pavement and evaporate from the subgrade. On the other hand, developing pavement cementitious mixtures able to retain high void contents and reach significant mechanical performance entails an in-depth analysis of materials and construction practices. Pervious concrete can indeed be placed using a standard paver as for asphalt mixtures but the compaction stage is usually demanded to the contractor practices: light steel hand-rollers or standard drum rollers are both used without an in-depth knowledge of compaction properties of the cementitious mixture. The present paper aims at investigating the influence of compaction methods on the mechanical performance and void contents of pervious concrete mixtures. Several compaction procedures were tested modifying the compaction energy and the mixture characteristics while preserving high permeability. The main objective was to simulate and identify the effect of commonly adopted in situ compaction techniques - i.e.: tamper compaction as provided by the paver, steel hand-roller compaction, or standard drum roller compaction. Results showed how the compaction energy, water/cement ratios, and the percentage of cement affect the Indirect Tensile Strength and void contents of the mixtures. Further investigations were also conducted in order to comprehensively evaluate how the variation in the percentage of cement and water/cement ratio influenced the stiffness of the material.

Стилі APA, Harvard, Vancouver, ISO та ін.

37

Poran, Chaim J., and Jorge A. Rodriguez. "Design of dynamic compaction." Canadian Geotechnical Journal 29, no. 5 (October 1, 1992): 796–802. http://dx.doi.org/10.1139/t92-087.

Повний текст джерела

Анотація:

In recent years dynamic compaction (DC) has become a popular method for deep improvement of loose cohesionless soils and man-made fills of disposed waste and rubble. One of the main problems facing design engineers and contractors is the assessment of the number of tamper drops, grid spacing, and layout of passes required to attain satisfactory improvement depth in the soil strata. Many DC sites have irregular subsurface conditions where it is difficult to interpret results from site exploration and verification tests. The industry has long been using a simple relationship to estimate the depth of improvement (influence depth). The estimates obtained from that empirical method may vary considerably and in many cases may be rendered useless for DC design. The paper describes a new, rational, and more comprehensive DC design method based on results from an extensive experimental model study of impact response in dry sand. Analysis of normalized impact energy and the resulting densification in the sand in terms of normalized dimensions of volumetric strain contours shows unique correlations that are used for the proposed design method for dynamic compaction in unsaturated sandy soils. Data from several DC sites fit well with the new method. With future studies of field results the proposed approach could eventually be calibrated and used for other types of soil conditions. Key words : dynamic compaction, design, impact, sandy soil, energy, plastic strains

Стилі APA, Harvard, Vancouver, ISO та ін.

38

Al-Shatib, Mohammed A. M., John McL Bennett, Guangnan Chen, and Troy A. Jensen. "Impact of cotton picker traffic on vertosol soil and yield in individual rows." Crop and Pasture Science 72, no. 7 (2021): 514. http://dx.doi.org/10.1071/cp20360.

Повний текст джерела

Анотація:

This study investigated the impact of soil compaction owing to cotton picker traffic, and the impact of this compaction on cotton yield on a row-by-row basis across the field under both random traffic farming (RTF) and controlled traffic farming (CTF) systems. Measurements of soil water content, dry bulk density and soil penetration resistance were taken and compared with a depth of 80 cm both before and after traffic. It was found that the traffic of JD7760 round-bale cotton picker caused significant compaction in cotton rows and furrows located between, adjacent to, and in wheel tracks under both RTF and CTF systems, particularly for the top 30-cm depth. Because of the soil compaction, the yield was more significantly reduced (7~10% by the machine-pick method) in the rows between the dual-wheel than in those adjacent to the wheel track. Adopting CTF reduces the area of soil compaction and ensures the maintenance of soil characteristics of the cultivated portions of the farm, hence enhancing cotton yield.

Стилі APA, Harvard, Vancouver, ISO та ін.

39

Lopes, Bruna de Carvalho Faria Lima, Vinícius de Oliveira Kühn, Ângela Custódia Guimarães Queiroz, Bernardo Caicedo, and Manoel Porfírio Cordão Neto. "Structure evaluation of a tropical residual soil under wide range of compaction conditions." Géotechnique Letters 12, no. 2 (June 1, 2022): 1–8. http://dx.doi.org/10.1680/jgele.21.00101.

Повний текст джерела

Анотація:

Soil compaction is one of the most common techniques used to engineer the soil. It is especially appealing to developing countries for its cost-effective and sustainable attributes for improving the soil's geotechnical characteristics. The compaction process along with the complexity of residual soils, abundant in the tropics zone, can have an impact on the performance of geotechnical structures built with these soils. Therefore, it is important to understand the influence that certain compaction conditions have on the structure of these materials. To investigate that, mercury intrusion porosimetry tests were performed on compacted samples of a tropical residual soil from Brazil under different conditions of water content and compactive effort. Results show that the compacted soil under all studied conditions presents a bimodal pore-size distribution (PSD). It appears that the low availability of water within the macro-pores, hence suction, could have played a decisive role in maintaining the bimodal framework of the PSD. In this respect, this study contributes to a better understanding of the tropical residual soils’ structure when subjected to different compaction conditions, thus providing means to improve field applications.

Стилі APA, Harvard, Vancouver, ISO та ін.

40

Cheng, Jinxiang, Dongbiao Zhao, Kai Liu, Yangwei Wang, and Huaiyuan Chen. "Modeling and impact analysis on contact characteristic of the compaction roller for composite automated placement." Journal of Reinforced Plastics and Composites 37, no. 23 (September 18, 2018): 1418–32. http://dx.doi.org/10.1177/0731684418798151.

Повний текст джерела

Анотація:

Composite automated placement shows great potential for efficient manufacturing of large aviation components. In order to understand the effect of the contact between the compaction roller and the fiber/tape on the layup quality, it is necessary to study the contact characteristic of the compaction roller and the morphological change of the prepreg under the compaction roller. The contact of the compaction roller is divided into the static and dynamic contact. For the static contact, the contact model is simplified to a roller compaction on an elastic body with curved surfaces, and it is developed based on the elastic contact theory. On the contrary, a dynamic contact model is presented by simplifying the contact areas as idealized rectangular elements with identically sized elements. Due to the compaction roller exerting pressure on the prepreg, the morphology of the prepreg will change with different processing parameters. The deformation model of the prepreg is determined as the resin flows through a porous network of fibers by creep theory. A series of experiments had been conducted to verify feasibility and accuracy of the developed models. Results demonstrate that these models have good precision.

Стилі APA, Harvard, Vancouver, ISO та ін.

41

Beddu, Arifin, Lawalenna Samang, Tri Harianto, and Achmad Bakri Muhiddin. "Interpretation of CBR Test Results Based on the Rapid Impact Compaction Electro-Mechanic System Model." MATEC Web of Conferences 203 (2018): 04003. http://dx.doi.org/10.1051/matecconf/201820304003.

Повний текст джерела

Анотація:

In order to understand the mechanical properties of the compaction results and to optimize the relevant energy design of the repeated Rapid Impact Compaction (RIC), a series of California Bearing Ratio (CBR) tests were performed on the compaction sample with RIC electro-mechanic system. In this laboratory test, samples were compacted at various RIC impact energy levels. A mass of different weight and various of falling height was used to compact the samples in a CBR cylindrical test. The mass was repeatedly dropped on the anvil plate with a frequency of 30-40 blows per minute. The compaction process carried out by varying number of blows from 5 to 35 for each compacted sample, and all compaction processes were controlled by electro-mechanic new development system. The test results represented that there was a variation of CBR value at the same RIC energy levels. The CBR values at the same energy level with the larger number of blow increased higher in lighter mass, whereas than the RIC energy level for larger masses with the smaller number of blows also occurred with the same trend to the result of relative compaction density test. This advantages that with a better understanding of RIC mechanisms and relevant energy designs, it is a new practical idea to improve compaction degree as well as CBR value on fill construction works with appropriate equipment and lower energy consumption.

Стилі APA, Harvard, Vancouver, ISO та ін.

42

Ceccato, Chiara, August Brandberg, Artem Kulachenko, and Christophe Barbier. "Micro-mechanical modeling of the paper compaction process." Acta Mechanica 232, no. 9 (July 6, 2021): 3701–22. http://dx.doi.org/10.1007/s00707-021-03029-x.

Повний текст джерела

Анотація:

AbstractDouble-roll compaction is a process to create extensible paper and paperboard suitable for replacing plastic in 3D forming applications. Understanding the macro- and micro-mechanisms governing the compaction process allows increasing the stretch potential while maintaining sufficient strength and bending stiffness. In this work, we approach the compaction process of paperboard with micro-mechanical methods featuring the unprecedented level of details otherwise inaccessible with currently available experimental tools. The loading scheme is based on experiments and continuum level simulations. The different levels of compaction and their continuous impact on the fibers’ geometry, void closures, and irreversible deformation of the fibers are thoroughly characterized. We find that the structural changes are concentrated in the fibers oriented within 30 degrees of the direction of compaction. The deformation accumulates primarily in the wall of the fibers in the form of irreversible strains. The spring-back effect beyond the compaction is negligible. For the first time, the role of normal and frictional fiber-to-fiber interactions in the compaction process is investigated and quantified. The frictional interaction between the fibers has a surprisingly low impact on the outcome of the compaction process, and the normal interaction between the fibers has a dominant response. The consequence of this finding is potentially limited impact of the surface modifications targeting the friction.

Стилі APA, Harvard, Vancouver, ISO та ін.

43

Chen, Jin, Zhi Yu Xiao, Chao Jie Li, San Cai Deng, Tung Wai Leo Ngai, and Yuan Yuan Li. "High Velocity Compaction of 316L Stainless Powder." Applied Mechanics and Materials 44-47 (December 2010): 2993–97. http://dx.doi.org/10.4028/www.scientific.net/amm.44-47.2993.

Повний текст джерела

Анотація:

High velocity compaction technology was used to press 316L stainless powders. Effects of impact times on stress wave, green density and ejection force were analyzed. It was found that under the same total impact energy, the first loading time and the actuation duration of the second impact in double impact process were longer when compared with single impact process, while the first delay time was shorter. Furthermore, the green density of compacts prepared by double impact was greater than that prepared by single impact, but no obvious variation in maximum ejection force can be observed between single impact and double impact process.

Стилі APA, Harvard, Vancouver, ISO та ін.

44

Mamy, Laure, Christian Mougin, Pierre Benoit, Sabine Houot, Agathe Brault, Nathalie Cheviron, Ghislaine Delarue, Valérie Dumeny, and Laure Vieublé-Gonod. "Effect of Multiple Stresses, Organic Amendment and Compaction, on the Fate and Impact of Isoproturon in Soil." Environments 7, no. 10 (September 29, 2020): 79. http://dx.doi.org/10.3390/environments7100079.

Повний текст джерела

Анотація:

Organic matter decline and compaction are two major processes of soil degradation. Organic amendment is a current practice to compensate the loss of organic matter, which could in addition contribute to increase soil aggregate stability and limit compaction. Therefore, the objective of this work was to study the effect of multiple physico-chemical stresses, organic amendment (compost of sewage sludge and green waste) addition and soil compaction, on the fate and impact (measured through the urease enzyme activity) of isoproturon. Compost addition and compaction did not significantly affect the fate and impact of isoproturon. The lack of effect of compost can be due to the delay between soil sampling and soil amendment. Compaction had no effect probably because the porosity reduction does not affect the habitable pore space accessible to degrading microorganisms. Nevertheless, isoproturon significantly increased the urease enzyme activity in compacted and not compacted unamended soils contrary to the amended ones. It seems that the organic amendment could act as a buffer with regards to the impact of isoproturon. The results obtained in this work suggest that, in general, the fate and impact of isoproturon in soils will not change following compaction and/or organic amendment addition, neither the corresponding risks for the environment.

Стилі APA, Harvard, Vancouver, ISO та ін.

45

Teng, Yun Nan, Li Yang Xie, and Bang Chun Wen. "Study on Vibration Friction Mechanism of Vibration Compaction System." Advanced Materials Research 706-708 (June 2013): 1594–97. http://dx.doi.org/10.4028/www.scientific.net/amr.706-708.1594.

Повний текст джерела

Анотація:

The mechanism model of vibration compaction system was built. The vibration friction mechanism of vibratory compaction system was studied based on granular dynamics theory. The results show that the void ratio does a great impact on strength and compaction.

Стилі APA, Harvard, Vancouver, ISO та ін.

46

Jiang, Yang, Yue Xin She, Wen Bin Sun, Bao Hai Chen, and Hua Rong Shen. "Consolidation Effect and Influencing Factors of Dynamic Compaction for Filling Subgrade." Applied Mechanics and Materials 204-208 (October 2012): 1617–21. http://dx.doi.org/10.4028/www.scientific.net/amm.204-208.1617.

Повний текст джерела

Анотація:

The parameters of dynamic compaction impacting on consolidation effect such as fall-height of hammer, impact mode, impact space, etc. are analysed by dynamic FEM method. The method of choosing parameters of dynamic compaction and consolidation effect of dynamic compaction on filling subgrade are illuminated by field test. Conclusions are drawn: with the increase of impact energy, the range of plastic deformation zone will extend to a certain depth in subgrade, which will certainly expand the effective reinforcement range of subgrade; optimal impact times of a subgrade is available; the consolidate depth and influencing area by light hammer with heavy impact is less than that by heavy hammer with light impact when impact energy is equal; with the increase of hammer diameter, both deformation and strain of subgrade reduce under the same impact energy.

Стилі APA, Harvard, Vancouver, ISO та ін.

47

PRANAGAL, JACEK JULIAN, DOROTA TOMASZEWSKA-KROJAŃSKA, HALINA SMAL, and SŁAWOMIR LIGĘZA. "Impact of selected waste applications on soil compaction." Agronomy Science 74, no. 3 (December 7, 2019): 19–32. http://dx.doi.org/10.24326/as.2019.3.2.

Повний текст джерела

Анотація:

In the years 2014–2017, a field experiment was carried out, in which two types of waste were applied to soil. One of them was mineral waste – carboniferous rock from a hard coal mine, and the other – organic waste – post-fermentation sludge from agricultural biogas-producing plant. The experiment was an example of an action, in which soil management was associated with their drainage effects on the soil. The waste was applied to the light soil of low utility value, included in the V bonitation class (in polish soil quality classification) and the 6th complex of agricultural suitability (weak rye). According to the WRB classification, it was Haplic Podzol (PZha) developed from the post-glacial sand. The aim of the study was to analyze changes in soil compaction caused by a single introduction of waste. During the four-year study (2014–2017), the durability of these changes was also observed. It was found that the best effects of reducing the soil compaction were obtained as a result of the combined application of two wastes: carboniferous rock and post-fermentation sludge. Introduction of waste into the soil was also permanent, as differences resulting from the soil management continued in the fourth year of the experiment.

Стилі APA, Harvard, Vancouver, ISO та ін.

48

Salam, A. Ejah Umraeni. "Prototipe Model Rapid Impact Compaction untuk skala laboratorium." JTEV (Jurnal Teknik Elektro dan Vokasional) 5, no. 1.1 (September 23, 2019): 39. http://dx.doi.org/10.24036/jtev.v5i1.1.106140.

Повний текст джерела

Анотація:

Penelitian ini bertujuan untuk mengembangkan model system pembebanan Repeated Load Tipe Rapid Impact Compaction dengan menggunakan sistem instrumentasi dengan proses akuisisi data untuk memperoleh data tekanan pada lapisan tanah, pola deformasi tanah dan tekanan air pori apabila dilakukan pembebanan. Untuk pengukuran tekanan pada lapisan tanah menggunakan sensor earth pressure cell, sedangkan untuk pengukuran deformasi tanah dan tekanan air pori digunakan sensor sensor ultrasonik dan pore water pressure sensor. Hasil pengukuran sistem ini akan divalidasi sesuai dengan rumus dan teori yang telah ada. Hasil yang diperoleh menunjukkan bahwa besarnya beban yang diberikan berbanding lurus dengan tekanan pada lapisan tanah. Begitupula dengan pengukuran tekanan air pori tanah yaitu untuk beban statis perbedaan presentase kesalahan antara teori dan praktek cukup kecil yaitu rata-rata presentase kesalahan berkisar 0,0475 %, sedangkan untuk beban dinamis, diperoleh bahwa tegangan air pori memilik batasan nilai, sehingga walaupun terjadi tumbukan lagi nilainya akan tetap. Untuk pengukuran deformasi tanah diperoleh peningkatan penurunan tanah sesuai dengan banyaknya jumlah tumbukan.

Стилі APA, Harvard, Vancouver, ISO та ін.

49

Hibino, Atsushi, Ichitaro Sato, and Hideaki Negishi. "Impact Compaction of Iron Powder by Electromagnetic Forming." Journal of the Japan Society of Powder and Powder Metallurgy 41, no. 3 (1994): 263–68. http://dx.doi.org/10.2497/jjspm.41.263.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

50

Corel'skii, V. A., and S. A. Zelepugin. "Numerical modeling of powder compaction with axisymmetrical impact." Soviet Powder Metallurgy and Metal Ceramics 31, no. 4 (April 1992): 291–95. http://dx.doi.org/10.1007/bf00796275.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Статті в журналах з теми "Impact compaction"

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями