To see the other types of publications on this topic, follow the link: Slab.
Journal articles on the topic 'Slab'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Slab.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Jiang, Zhou Hua, and Xin Geng. "Research on the Surface Quality of ESR Large Slab Ingots." Advanced Materials Research 146-147 (October 2010): 670–73. http://dx.doi.org/10.4028/www.scientific.net/amr.146-147.670.
Full textAbstract:
A special bifilar 40t electroslag remelting(ESR) furnace for slab products has been fabricated to produce heavy plates for special application. The ESR slabs with the maximum thickness of the world in size of 980 mm thickness, 2000 mm wideness and 2800 mm length have been produced successfully. However, the ingots surface quality is a serious problemn in ESR process for large slab ingots, for ingot and mold with a relatively mobile, larger ingot contraction and thicker slag skin. Using CaF2-CaO-Al2O3-SiO2-MgO slag, suited remelting rate, lower filling ration, smooth movement of mold and adjusting taper of the mold and are necessary for improving surface quality of the ESR large slab ingots.
2
Amer M. Ibrahim, Nazar K. Ali, and Wissam D. Salman. "Flexural Capacities of Reinforced Concrete Two-Way Bubbledeck Slabs of Plastic Spherical Voids." Diyala Journal of Engineering Sciences 6, no. 2 (June 1, 2013): 9–20. http://dx.doi.org/10.24237/djes.2013.06202.
Full textAbstract:
This paper presents the flexural capacities of R.C two way hollow slabs of plastic spherical voids, also known as BubbleDeck slab system. Recently, various types of slab systems which can reduce the self-weight of slabs have been studied as the height and width of building structures rapidly increase (1). A biaxial hollow slab system is widely known as one of the effective slab systems which can reduce the self-weight of slabs (1). A BubbleDeck slab has a two-dimensional arrangement of voids within the slabs to reduce self-weight (2). The behavior of BubbleDeck slabs is influenced by the ratio of bubble diameter to slab thickness. To verify the flexural behavior of this BubbleDeck slab such as ultimate load, deflection, concrete compressive strain and crack pattern, two-dimensional flexural tests were tested by using special loading frame. Six test of specimens were used. Two were a conventional RC slab and four were BubbleDeck slabs having void diameter to slab thickness ratios of (0.51, 0.64 and 0.80). Results have shown that the crack pattern and flexural behavior depend on the void diameter to slab thickness ratio. The ultimate load capacities for BubbleDeck slabs having bubble diameter to slab thickness of (0.٥1 and 0.64) were the same of solid slabs, while when bubble diameter to slab thickness of (0.80) the ultimate capacities were reduced by about (10%).
3
Peng, Qi Chun, Xue Sen Yu, Wei Xiong, Liu Yang, Liang Zhou Zhang, Ming Yao Peng, and Ming Wei Zhou. "Study on Cleanliness of Ultra-Low Carbon Steel First Slab." Advanced Materials Research 524-527 (May 2012): 2037–43. http://dx.doi.org/10.4028/www.scientific.net/amr.524-527.2037.
Full textAbstract:
By means of Oxygen and Nitrogen Analyzer, Metallographic Examination, SLIME, SEM, EDS, etc, the cleanliness of ultra-low carbon steel first slab produced by LD-RH-CC, and the comparative analysis with the cleanliness of normal slab is studied. The results show that T[O] and [N] are obviously decreasing with the increasing of casting length. The micro-inclusions and large-inclusions are generally decreasing with the increasing of casting length. The micro-inclusions of the first slab are mainly from deoxidization products and reoxidation of liquid steel. And the sources of large-sized inclusions mainly are reoxidation of liquid steel, slag entrapment in mould or tundish and stuffing sand. The cleanliness of ultra-low carbon steel first slab is closed to those normal slabs at the length of 3.5m.
4
Kim, Byoung Hoon, Joo Hong Chung, Hyun Ki Choi, Seung Chang Lee, and Chang Sik Choi. "Flexural Capacities of One-Way Hollow Slab with Donut Type Hollow Sphere." Key Engineering Materials 452-453 (November 2010): 773–76. http://dx.doi.org/10.4028/www.scientific.net/kem.452-453.773.
Full textAbstract:
This paper presents the flexural capacities of one-way hollow slab with donut type hollow sphere. Recently, various types of slab systems which can reduce self-weight of slabs have been studied as the height and width of building structures rapidly increase. A biaxial hollow slab system is widely known as one of the effective slab system which can reduce self-weight of slab. A biaxial hollow slab has hollow spheres within slabs in order to reduce self-weight of slabs. The capacities of biaxial hollow slab are influenced by the shapes, volume and materials of hollow spheres. According to analytical studies, the hollow slab with donut type hollow sphere had good flexural capacities such as strength, stiffness and deflection. To verify the flexural capacities of this hollow slab, flexural tests were performed on the one-way hollow slabs. Five test specimens were used for test parameters. One was conventional RC slab and others were hollow slabs. The test parameters included two different shapes and materials of plastic balls. The shape parameters were donut and non-donut forms. And the material parameters were general plastic and glass fiber plastic.
5
Khairussaleh, Nor Ashikin Muhammad, Ng Kah Hoe, and Gerald A. R. Parke. "Effect of Area Loading on Flexural Performance of Bubble Deck Slab." Key Engineering Materials 912 (March 4, 2022): 41–54. http://dx.doi.org/10.4028/p-51xde0.
Full textAbstract:
Reinforced bubble deck slab is a structural slab that contains high-density polyethene (HDPE) hollow spherical plastic bubble balls forming a slab with less concrete volume compared to the normal reinforced concrete slab. Reducing certain volumes of concrete from 30 to 50% will affect the performance of the slab structure in particular the flexural and shear capacity. Thus, in this research the effect of area loading on the flexural performance of bubble deck slabs is investigated by considering the slabs to be one-way supported slabs. The square deck slabs used were 1200mm by 1200mm for the width and length with a thickness of 230mm. A total of 36 HDPE hollow spherical plastic bubble balls with a 180mm diameter were placed in the bubble deck slab specimens which reduce significantly the structural self-weight. In this paper, the experimental results of the flexural performance of the reinforced bubble deck slab, (BD slab) compared with a conventional reinforced concrete slab, simply supported, subjected to static area loadings, are presented. The effect of the load applied in the experiments on the flexural strength, bending stiffness and load-deflection behaviour of both types of slabs have been discussed including the crack propagation and crack pattern. In general, the conventionally reinforced solid slab, simply supported (SS) has a 60.6% higher resistance against bending deformation than the reinforced bubble deck slab.
6
Gupta, Sushant, and Sanjeev Naval. "Analysis of Orthotropic RC Rectangular Slabs Supported on Two Adjacent Edges - A Simplistic Approach." Civil Engineering Journal 6, no. 10 (October 1, 2020): 1992–2001. http://dx.doi.org/10.28991/cej-2020-03091598.
Full textAbstract:
The design of reinforced concrete slabs supported on two adjacent edges involves complex formulations. In this paper, a simplistic approach is presented for designing orthotropic slabs supported on two adjacent edges. Slab supported on two adjacent edges (existing slab) is transformed into a slab supported on three edges (equivalent slab) by taking a mirror image of the yield line pattern of two adjacent edges supported RC slabs about its unsupported edges to get the exact collapse mechanism for the slabs supported on three edges. The equivalent aspect ratio can be used in the equations already developed for the slabs supported on three sides. Ultimate moment carrying capacity of the slab carrying uniform load can be evaluated by using the available analytical formulations of the slab supported on three edges. So, the present approach gives a simplified method to analyse and design the orthotropic RC rectangular slab supported on two adjacent edges using the equations available for slab supported on three adjacent edges. Hence, the simplistic approach will be very helpful for structural designers dealing with analysis and design of slabs supported on two adjacent edges. Doi: 10.28991/cej-2020-03091598 Full Text: PDF
7
Yaagoob, Ali H., and Ibrahem S. Harba. "Behavior of Self Compacting Reinforced Concrete One Way Bubble Deck Slab." Al-Nahrain Journal for Engineering Sciences 23, no. 1 (March 20, 2020): 1–11. http://dx.doi.org/10.29194/njes.23010001.
Full textAbstract:
Reinforced concrete slab with plastic voids (Bubbled Deck system) is a new type of slabs which has two-dimensional arrangement of voids within the slab that is developed to decrease the slab self-weight while maintaining approximately the same load carrying capacity as compared with the solid slabs. Plastic voided slabs have the ability to reduce concrete amount by about 30 percent and this reduction is so important in terms of cost saving and enhancement the structural performance. In this research paper investigation is carried out to study the shear strength behavior of one-way bubble deck slab using self-compacting reinforced concrete. The experimental program consists of testing thirteen one-way slabs with dimensions of (1700 length, 700 width and 150 thick) mm. One of the tested slabs is a solid slab (without balls) is used as a reference, the remaining twelve bubbled slabs with ball diameter (73, 60) mm are divided into five groups according to the parameters of the experimental work, the parameters of the experimental work include: type of slab (bubble and solid slabs), ball diameter (73, 60) mm, shear reinforcement and spacing between balls. The experimental results showed that the bubbled slabs without shear reinforcement have a decrease in the ultimate load as compared to solid slab by about 3.7% to 14.3% and an increase in the deflection at ultimate load by about 10% to 22%, at the same time the first crack load decreases by about 15.3% to 42.4% as compared to solid slab due to decreases of moment of inertia of bubble slab compared to solid slab. Also, the results showed that the bubbled slabs withe shear reinforcement (multi-leg) have an increase in the ultimate load as compared to solid slab by about 35.4% to 57.3% and an increase in the deflection at ultimate load by about 1% to 15%, at the same time the first crack load decreases by about 2.8% to 27.4% as compared to solid slab.
8
Liu, Yu, Yuanpeng Tian, Xudong Wang, and Yali Gao. "Influence of processing parameters on slab stickers during continuous casting." High Temperature Materials and Processes 39, no. 1 (June 30, 2020): 228–35. http://dx.doi.org/10.1515/htmp-2020-0065.
Full textAbstract:
AbstractIn this study, the parameters of 44 sticker breakout samples were analysed. The research mainly focused on the steel grades and slab thickness of stickers. Other processing parameters, such as slab width, casting speed, mould fluctuation, heat flux and operation, were also discussed. The results show that the number of stickers of low carbon steel and low alloy steel was 16 and 28, respectively. The stickers of low carbon steel were less than those of low alloy steel regardless of the thickness and width. The ratio of stickers per 1,000 casting heats of 220, 260 and 320 mm thickness slabs was 2.5, 0.5 and 0.6, respectively. The higher casting speed of 220 mm thickness slabs made the casting status unsteady and caused more stickers. From the perspective of width, the stickers were gradually increased along with the increase in width due to the worse mould slag. This study provides a foundation to reduce slab stickers and is helpful for a more efficient technology of continuous casting.
9
Gao, Ju, and Cheng Liang Du. "Study of Large Inclusions in Casting Slab of 45# Steel." Advanced Materials Research 634-638 (January 2013): 1859–63. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.1859.
Full textAbstract:
According to the production process of 45#steel(120t BOF→ slag refining →CC), some system analysis are introduced to research on the type, composition and quantity of large inclusions in casting slab under slag washing process, the effect of slag washing production process on the cleanliness of casting slab is evaluated. The results of the study show that: Under slag washing process, many of large inclusions are spherical inclusions，the main type of large inclusions is CaO-SiO2-Al2O3-MnO complex inclusion andSiO2-Al2O3 inclusion; the content of large inclusions in normal slab is 5.17mg/10kg, it is lower than that under un-slag washing process; the content of large inclusions in head slab is 108.82mg/10kg, it’s 21.05 times higher than that in normal slab; the content of large inclusions in compound casting slab is 15.94mg/10kg, it’s 3.08 times higher than that in normal slab; the content of large inclusions in casting slab is slightly higher under the condition of unsteady casting; the main inclusions with a size of between 140μm and 300μm in head slab, take up 70.13%, the inclusions with a size of more than 300μm is second, take up 29.24%, and the least is inclusions with a size of between 80μm and 140μm, only take up 0.63%. The level of the molten steel fluctuated remarkably, slag entrapment and secondary oxidation is serious at the casting start and compound casting, which cause the cleanliness of casting slab decreasing. Unsteady casting has great effect on the cleanliness of casting slab.
10
M. Ibrahim, Amer. "Effect of Construction Type on Structural Behaviour of R.C Bubbled One-Way Slab." DJES 12, no. 1 (March 1, 2019): 73–79. http://dx.doi.org/10.24237/djes.2019.12109.
Full textAbstract:
Using Bubbles in the slab is a revolutionary method of eliminating concrete from the middle of conventional slab as this concrete does not perform any structural function, thereby dramatically reducing structural dead weight. This research presents experimental study to investigate the effect of construction type on the strength and behaviour of bubbled one-way slabs. The experimental program consists of testing four slabs with dimensions of 1850mm×460mm×110 mm. One1of the tested slabs was conventional slab (without bubbles), two bubbled slabs with different types of construction (simple and filigree bubbled slabs) and the remaining one is filigree bubbled slab strengthened with steel cage. The bubbles were made of recycled plastic balls. The experimental results show that the stiffness reduction factor for all the bubbled slabs was (0.87), this leads to decrease the ultimate strength of bubbled slabs and to be smaller than that of the solid slab by 4.4% 69% and 1.7% respectively. Also an increase in deflection at yield load (∆y) by about (10% to 12%), at the same time the crack load is found to be decreased by (13% to 40%). The simple bubbled slab is more efficient when compared with filigree bubbled slab. Also the results show that the use of steel cage in filigree bubbled slab gives an increase in the ultimate load by 69% and an increase in the ultimate deflection by about 77% when compared with filigree bubbled slab without steel cage.
11
Chung, Joo-Hong, Hyung-Suk Jung, and Hyun-Ki Choi. "Flexural Strength and Stiffness of Donut-Type Voided Slab." Applied Sciences 12, no. 12 (June 7, 2022): 5782. http://dx.doi.org/10.3390/app12125782.
Full textAbstract:
The voided slab system has been known as an effective technique to replace a heavy reinforced concrete slab system without the decrease in flexural strength. However, according to the previous studies, the flexural capacities such as flexural strength, stiffness and ductility of the voided slabs were practically lower than that of the solid slabs depending on the void shapes and details. Therefore, in this study, an analytical and experimental study were conducted to derive the optimal void shape and details focused on the flexural capacities of voided slabs. Based on a finite element (FE) analysis, a donut-type void shaper, which was a hexahedron with rounded edges and a hole penetrating the center, was suggested as the optimal shape in voided slabs, and an experimental study was conducted to verify flexural capacities of the donut-type voided slab. The flexural strength, stiffness and deflection of the donut-type voided slab were investigated by void shape and fixing method of void shaper as variables. The ductility of voided slab was also evaluated, because ductility is as important as strength for the safe design of slab member. The test results showed that the flexural strength of the donut-type voided slabs was equivalent to 98% and 105% that of the solid RC specimen, and the donut-type voided slab specimens had enough ductility for the flexural member. The stiffness of the donut-type voided slab was decreased about 8~9% compared with the solid slab, but it was improved up to 7% compared to the non-donut-type voided slab. Based on test results, the flexural design method of the donut-type voided slab associated with the void shape and fixing device of void shaper was suggested, and it was confirmed that the donut-type voided slab is one of the efficient alternatives to replace heavy flat plate slabs.
12
Sawwalakhe, Abhijit K., and Prabodh D. Pachpor. "Comparative Study Of Conventional Slab, Flat Slab And Grid Slab Using ETABS." IOP Conference Series: Materials Science and Engineering 1197, no. 1 (November 1, 2021): 012020. http://dx.doi.org/10.1088/1757-899x/1197/1/012020.
Full textAbstract:
Abstract In today’s construction, the traditional slab is mostly supported by a beam, with a small slab thickness and a large beam depth, and the weight is carried from beam to column. The flat slab allows architects to place partition walls wherever they are needed. It is widely used because it reduces weight, speeds up building, and is cost effective. Similarly, since its inception, the conventional slab has provided benefits such as increased stiffness, increased weight carrying ability, as well as being safe and cost effective. Grid slabs are necessary where the span is greater, and grid beams are provided to lessen the spanning. Grid slabs reduce dead load due to voids and are appropriate for longer spans with heavy loads. The Grid slab is less expensive and provides superior vibration resistance. The project’s goal is to find the most cost-effective slab among standard slab, flat slab with drop, and grid slab. A G+5 Commercial multi-story structure with flat slab, conventional slab, and gird slab was investigated for characteristics such as storey displacement, shear force, bending moment, and storey drift in this study. There are a total of 18 structures examined. The performance and behaviour of all structures in India’s seismic zone III have been investigated with the application of dead load, live load and seismic load. The results of shear force, Bending Moment, story shear, story displacement, story drift and quantity of concrete and steel shows that the overall result values makes flat slab a suitable structure as compared to the conventional and grid slab.
13
Portner, Daniel Evan, and Gavin P. Hayes. "Incorporating teleseismic tomography data into models of upper mantle slab geometry." Geophysical Journal International 215, no. 1 (July 12, 2018): 325–32. http://dx.doi.org/10.1093/gji/ggy279.
Full textAbstract:
SUMMARY Earthquake-based models of slab geometry are limited by the distribution of earthquakes within a subducting slab, which is often heterogeneous. The fast seismic velocity signature of slabs in tomography studies is independent of the distribution of earthquakes within the slab, providing a critical constraint on slab geometry when earthquakes are absent. In order to utilize this constraint, researchers typically hand-contour images of subducting slabs in tomography models, leading to a subjective final slab model. With this paper, we present an automated procedure for extracting slab geometry from teleseismic tomography volumes that limits this subjectivity and provides constraints on the structure of aseismic segments of slabs. This procedure is designed as a complement to earthquake-based slab models rather than as a replacement, which can help to broaden the extent of existing subduction zone geometry databases.
14
Lee, Seokjae, Sangwoo Park, Minkyu Kang, and Hangseok Choi. "Field Experiments to Evaluate Thermal Performance of Energy Slabs with Different Installation Conditions." Applied Sciences 8, no. 11 (November 10, 2018): 2214. http://dx.doi.org/10.3390/app8112214.
Full textAbstract:
The energy slab is a novel type of horizontal Ground Heat Exchanger (GHEX), where heat exchange pipes are encased in building slab structures. The thermal performance of energy slabs is usually inferior to the conventional closed-loop vertical GHEX because its installation depth is relatively shallow and therefore affected by ambient air temperature. In this paper, heat exchange pipes were made of not only conventional high-density polyethylene (HDPE), but also stainless steel (STS), which is expected to enhance the thermal performance of the energy slabs. In addition to a floor slab, a side wall slab was also used as a component of energy slabs to maximize the use of geothermal energy that can be generated from the underground space. Moreover, a thermal insulation layer in the energy slabs was considered in order to reduce thermal interference induced by ambient air temperature. Consequently, two different field-scale energy slabs (i.e., floor-type and wall-type energy slabs) were constructed in a test bed, and two types of heat exchange pipes (i.e., STS pipe and HDPE pipes) were installed in each energy slab. A series of thermal response tests (TRTs) and thermal performance tests (TPTs) were conducted to evaluate the heat exchange performance of the constructed energy slabs. Use of the STS heat exchange pipe enhanced the thermal performance of energy slabs. Additionally, the wall-type energy slab had a similar thermal performance to the floor-type energy slab, which infers the applicability of the additional use of the wall-type energy slab. Note that if an energy slab is not thermally cut off from the building’s interior space with the aid of thermal insulation layers, heat exchange within the energy slabs should be significantly influenced by fluctuations in ambient temperature.
15
Wang, Xiao Wei, Wen Ling Tian, Zhi Yuan Huang, Ming Jie Zhou, and Xiao Yan Zhao. "Analysis on Punching Shear Behavior of the Raft Slab Reinforced with Steel Fibers." Key Engineering Materials 400-402 (October 2008): 335–40. http://dx.doi.org/10.4028/www.scientific.net/kem.400-402.335.
Full textAbstract:
The thickness of the raft slab is determined by punching shear. The raft slab is commonly thick, which causes concrete volume is large. Mass concrete can bring disadvantage to the foundation. In order to increase the bearing capacity and reduce the thickness, it is suggested that the raft slab to be reinforced by steel fibers. There are five groups of specimens in this paper. S1 is the common reinforced concrete slab. S2 and S3 are concrete slabs reinforced by steel fibers broadcasted layer by layer when casting specimen. S4 and S5 are concrete slabs reinforced by steel fibers mixed homogeneously when making concrete. The punching shear tests of these slabs were done. The test results indicate that the punching shear capacity of the slab reinforced with steel fibers is higher than that of concrete slab, the stiffness and crack resistance of the steel fibers reinforced concrete slab are better than those of the common concrete slab and the punching shear of the slabs with different construction methods of steel fibers is similar. It analyses the punching shear behavior of the slab reinforced with steel fibers and suggests the ultimate bearing formula. The calculative values are coincided with the measured values well.
16
Galishnikova, Vera V., Alireza Heidari, Paschal C. Chiadighikaobi, Adegoke Adedapo Muritala, and Dafe Aniekan Emiri. "Ductility and flexure of lightweight expanded clay basalt fiber reinforced concrete slab." Structural Mechanics of Engineering Constructions and Buildings 17, no. 1 (December 15, 2021): 74–81. http://dx.doi.org/10.22363/1815-5235-2021-17-1-74-81.
Full textAbstract:
Relevance. The load on a reinforced concrete slab with high strength lightweight aggregate concrete leads to increased brittleness and contributes to large deflection or flexure of slabs. The addition of fibers to the concrete mix can improve its mechanical properties including flexure, deformation, toughness, ductility, and cracks. The aims of this work are to investigate the flexure and ductility of lightweight expanded clay concrete slabs reinforced with basalt fiber polymers, and to check the effects of basalt fiber mesh on the ductility and flexure. Methods. The ductility and flexural/deflection tests were done on nine engineered cementitious composite (expanded clay concrete) slabs with dimensions length 1500 mm, width 500 mm, thickness 65 mm. These nine slabs are divided in three reinforcement methods types: three lightweight expanded clay concrete slab reinforced with basalt rebars 10 mm (first slab type); three lightweight expanded clay concrete slab reinforced with basalt rebars 10 mm plus dispersed chopped basalt fiber plus basalt fiber polymer (mesh) of cells 2525 mm (second slab type); three lightweight expanded clay concrete slab reinforced with basalt rebars 10 mm plus dispersed basalt fiber of length 20 mm, diameter 15 m (third slab type). The results obtained showed physical deflection of the three types of slab with cracks. The maximum flexural load for first slab type is 16.2 KN with 8,075 mm deflection, second slab type is 24.7 KN with 17,26 mm deflection and third slab type 3 is 32 KN with 15,29 mm deflection. The ductility of the concrete slab improved with the addition of dispersed chopped basalt fiber and basalt mesh.
17
Wang, Yifan, Tianlai Yu, Linlin Zhang, Lihui Yin, Yuxuan Wu, and Binglin Chen. "Fatigue Performance of Rib Beam Bridge Slabs Reinforced with Polyurethane Concrete Based on the Damage Theory." Buildings 12, no. 6 (May 24, 2022): 704. http://dx.doi.org/10.3390/buildings12060704.
Full textAbstract:
In this paper, the rib beam bridge slabs were taken as the research object. Static load and fatigue tests were carried out on the benchmark bridge slabs to determine the ultimate load capacity and fatigue life of the bridge slabs. Then, the bridge slab was pre-damaged and reinforced with polyurethane concrete. A fatigue test was carried out on the reinforced bridge slab to study the fatigue performance. Based on the damage theory, the fatigue damage reinforcement finite element models of the bridge slabs under different damage degrees were established. The fatigue performance of the reinforced bridge slabs was systematically studied. The results show that the fatigue damage of the reinforced bridge slab developed in stages. Compared to the unreinforced bridge slab, the fatigue damage of the reinforced bridge slab was significantly reduced at each stage. According to the least square method and numerical analysis results, a residual-bearing-capacity model including damage degree and fatigue cycles of the reinforced bridge slabs is proposed, which can be used as a reference in bridge slab reinforcement design.
18
Jendzelovsky, Norbert, and Kristina Zabakova Vrablova. "Comparison of Natural Frequencies of Hollow Core Slabs." Applied Mechanics and Materials 769 (June 2015): 225–28. http://dx.doi.org/10.4028/www.scientific.net/amm.769.225.
Full textAbstract:
This article is devoted to the calculation of natural frequencies of concrete slabs. Natural frequencies of a solid slab and a hollow core slab have been compared. Solid slab and lightened slab with reduced self-weight and stiffness have been modeled using FEM software ANSYS as 2D model using shell elements. Third model was made from 3D elements as a hollow core slab. Two types of boundary conditions have been considered: a simply supported slab and a clamped slab. The changes in natural frequencies according to aspect ratio of the slab were compared, too. Numerical methods have been compared with simplified method of calculation of natural frequency of slabs, as e.g. an equivalent plate approach; approximation presented by Hearmon and compilation of formulas by Bachmann.
19
Geng, Xing, Zhou Hua Jiang, Fu Bin Liu, and Hao Peng. "Manufacturing of Heavy Plates with Excellent Mechanical Properties by a 40t ESR Furnace for Slab Products." Advanced Materials Research 79-82 (August 2009): 1747–50. http://dx.doi.org/10.4028/www.scientific.net/amr.79-82.1747.
Full textAbstract:
A special bifilar 40t electroslag remelting(ESR) furnace for slab products has been fabricated to produce heavy plates for special application. The slab ingots were rolled to heavy plates, and then the mechanical properties of which were investigated. The impact toughness of heavy plates with different position, directions and under welding condition were performed at the temperature ranging from -70°C to room temperature. The tensile experiments at room temperature were carried out to check the tensile properties of heavy plates in different position, directions and under welding condition. The secondary cooling technology developed improves greatly the quality of solidification. Adjusting taper of the mold and using CaF2-CaO-Al2O3-SiO2-MgO slag are necessary for improving surface quality of the ESR slab. The ESR slabs with the maximum thickness of the world in size of 980 mm thickness, 2000 mm wideness and 2800 mm length have been produced successfully. The heavy plates with 410 mm in thickness can be obtained after rolling the 40 tons ESR slabs. The results of mechanical properties show that the heavy plates produced by ESR furnace for slab products exhibits excellent ductility, impact and isotropic properties in different position, directions and under welding condition.
20
Al-Ahmed, Ali Hussein Ali, Falah Hasan Ibrahim, Abbas AbdulMajeed Allawi, and Ayman El-Zohairy. "Behavior of One-Way Reinforced Concrete Slabs with Polystyrene Embedded Arched Blocks." Buildings 12, no. 3 (March 10, 2022): 331. http://dx.doi.org/10.3390/buildings12030331.
Full textAbstract:
This study presents experimental and numerical investigations on seven one-way, reinforced concrete (RC) slabs with a new technique of slab weight reduction using polystyrene-embedded arched blocks (PEABs). All slabs had the same dimensions, steel reinforcement, and concrete compressive strength. One of these slabs was a solid slab, which was taken as a control slab, while the other six slabs were cast with PEABs. The main variables were the ratio of the length of the PEABs to the length of the slab (lp/L) and the ratio of the height of the PEABs to the total slab depth (hP/H). The minimum decrease in the ultimate load capacity was about 6% with a minimum reduction in the slab weight of 15%. In contrast, the maximum decrease in the ultimate load capacity was about 24% with a maximum reduction in the slab weight of 40%. Moreover, the mode of failure changed from flexure to shear failure, especially for those slabs with an lP/L ratio equal to one. The geometric and material non-linearity was adopted in the proposed finite element (FE) model to simulate the slabs with PEABs using Abaqus software. Good agreement was obtained between the developed FE and experimental results.
21
Alfeehan, Ashraf Abdulhadi, Hassan Issa Abdulkareem, and Shahad Hameed Mutashar. "Flexural behavior of sustainable reactive powder concrete bubbled slab flooring elements." Challenge Journal of Structural Mechanics 3, no. 2 (June 13, 2017): 81. http://dx.doi.org/10.20528/cjsmec.2017.04.010.
Full textAbstract:
Voided slabs are reinforced concrete slabs in which voids allow to reduce the amount of concrete. The bubbled deck slab is a new and sustainable biaxial floor system to be used as a self-supporting concrete floor. The use of voided slabs leads to decrease the consumption of materials and improve the insulation properties for enhancing the objectives of sustainability. This study presents an investigation into the flexural behavior of sustainable Reactive Powder Concrete RPC bubbled slab flooring elements. Six one-way slabs were cast and tested up to the failure. The adopted variables in this study are: the volumetric ratio of steel fibers, type of slab; bubbled or solid, placing of reinforcement and thickness of slab. The effect of each variable on the ultimate load, deflection and strain has been discussed. The results show that increasing the percent of steel fibers from 1% to 2% in solid and bubbled slabs decreases the deflection by (18.75%) and (50%) respectively. As well as, the deflection increases by (41%) for bubbled slab compared to the solid slab. The slabs reinforced with top and bottom steel meshes show less deflection than slabs reinforced by only bottom steel mesh.
22
Abdullah, Mazin Diwan, and Khamail Abdul-Mahdi Mosheer. "Effect of Stirrups on the Behavior of Semi-Precast Concrete Slabs." Civil Engineering Journal 8, no. 8 (August 1, 2022): 1653–64. http://dx.doi.org/10.28991/cej-2022-08-08-09.
Full textAbstract:
A semi-slab of precast concrete (or half-slab) is a structural system that consists of concrete at the bottom half of a slab and concrete cast in situ at the top. To avoid traditional formwork and minimize the bottom half of the slab, this section can function as formwork and reduce the thickness of precast slabs, which makes their transportation easy. The interface between precast and overtopping concrete is effective for the slab system's performance. To improve the half-slab floor system, it is needed to have a shear connector (stirrups). Therefore, to better understand the behavior of this slab system, six full-scale slab specimens (2×7.5 m) with different shapes of the stirrups and spacing between them were constructed for this study. One specimen was produced with no connections and served as a reference specimen, while the other employed stirrups to connect slab units. The tests found that the distribution and type of stirrups affect the structural performance of the semi-precast concrete slab. The maximum load capacity of slabs with rectangular or triangular connections was nearly more significant than reference slabs, reaching 136.11 and 86.11%, respectively. The maximum load increased by 81.4 % for rectangular connections and 54.9% for triangular connections when the distance between the connectors was reduced from 600 to 300 mm. Furthermore, stirrups in semi-precast slabs could improve the cracking behavior, stiffness, and ductility. Doi: 10.28991/CEJ-2022-08-08-09 Full Text: PDF
23
Hulke, Pankaj, and S. S. Solanke. "Comparative Study of Different Types of Slab for Same Structural Condition." IOP Conference Series: Earth and Environmental Science 1193, no. 1 (June 1, 2023): 012001. http://dx.doi.org/10.1088/1755-1315/1193/1/012001.
Full textAbstract:
Abstract The regular slab is often supported by a beam in modern construction, With a modest slab width and a big beam deep, the weight is transmitted from beam to column. Because of the flat slab, architects may construct partition walls wherever they are required. It is popular since it assists with weight reduction, stimulates quick development, and is did-not expensive. Similarly, since its debut, the classic slab has brought benefits such as greater rigidity. It offers a higher weight bearing capacity while also being good and economical. Grid slabs are required if the span is higher than one span, while grid beams are given if the span is less than one span. Grid slabs are good for longer spans with large loads because they eliminate voids that would otherwise result in dead load. Some slabs are less costly and more resistant to vibration. The study’s purpose is to determine which of the three slab varieties, regular slab, flat slab with drop, and grid slab, is the most benefits. a G+5 This study looked at storey displacement, shear force, bending moment, and storey drift in a residential multi-story structure with different slab.
24
Ruan, Xuanqi, Deshen Chen, Yan Zhang, Zimeng He, Yaning Li, and Baiping An. "MECHANICAL PROPERTIES OF A NEW FULLY PREFABRICATED STAGGERED FLIP-DOWN SLAB." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 29, no. 4 (March 13, 2023): 318–28. http://dx.doi.org/10.3846/jcem.2023.18597.
Full textAbstract:
Prefabricated slab has been widely used in the global construction industry due to energy saving, environmental protection, and good economic advantages. In this paper, a new type of fully prefabricated staggered flip-down slab without cast-in-situ operation has been proposed. First, the experiments were carried out on the new slab. The structural performance of the new slab was compared with the cast-in-situ slabs and composite slabs of the same specification. The experimental results showed that the ultimate bearing capacity of the new slab meets the requirements for practical utilization. On this basis, an additional CFRP sheet could be pasted on the bottom initial seam between prefabricated slabs to enhance the integrity and prevent cracks. Then, the whole loading process of the slab was simulated, and the results were consistent with the experimental results. Finally, through experiments and parametric analysis, recommendations for improvement were put forward to enhance the mechanical properties of this kind of slab.
25
Athare, Shubham, and Prof A. U. Bhalerao. "Cost Analysis of Solid Slab and Voided Slab - A Review." International Journal for Research in Applied Science and Engineering Technology 11, no. 6 (June 30, 2023): 2350–52. http://dx.doi.org/10.22214/ijraset.2023.54054.
Full textAbstract:
Abstract: A novel and inventive structural system for concrete slabs, called plastic voided slabs, has been developed. This system incorporates plastic voids within the reinforced concrete slab, resulting in a lighter self-weight for the structure without compromising its load-bearing capacity compared to a solid slab. This study aims to compare the design process of plastic voided slabs with that of reinforced concrete solid flat slabs. Specifically, the design of typical bays with identical thickness is analyzed to assess the differences between the two systems.
26
Ali H. Aziz. "PUNCHING SHEAR AND FLEXURAL STRENGTHS OF SELF COMPACTED CONCRETE NON-RECTANGULAR SHAPED FLAT PLATE SLABS." Diyala Journal of Engineering Sciences 4, no. 1 (June 1, 2011): 95–107. http://dx.doi.org/10.24237/djes.2011.04107.
Full textAbstract:
This study is conducted to investigate experimentally the punching shear and flexural strengths of reinforced concrete flat plate slabs made with Non-Rectangular (triangular and trapezoidal) shaped. Four test self-compacting concrete slab groups were manufactured, each of which consisted of three slab specimens identical in size and shape but different in constituent’s properties. All slabs are simply supported along the all edges and subjected to single point load applied at the center of gravity of each slab.
Experimental results shows that the use of self compacting concrete improves the punching shear resistance and allows higher forces to be transferred through the slab-column connection. For slabs which were designed to fail in punching shear, the ultimate capacity of the tested specimens increased by (7%) to (20%) when the shape of slab specimens changed from triangular to trapezoidal. In contrast of slabs which were designed to fail in flexure, the ultimate capacity of the tested specimens increased from (16%) to (58%) when the shape of slab specimens changed from triangular to trapezoidal.
The cracking load depends essentially on concrete strength and not on slab configuration, but, the ultimate capacity depends on both, concrete strength and shape of slab.
27
Valivonis, Juozas, Bronius Jonaitis, Robertas Zavalis, Tomas Skuturna, and Arnoldas Šneideris. "FLEXURAL CAPACITY AND STIFFNESS OF MONOLITHIC BIAXIAL HOLLOW SLABS." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 20, no. 5 (October 20, 2014): 693–701. http://dx.doi.org/10.3846/13923730.2014.917122.
Full textAbstract:
The article presents a research on flexural behaviour of hollow monolithic reinforced concrete slabs. It focuses on the results of experimental investigation into full-size hollow reinforced concrete slabs and analyses their flexural capacity and stiffness. The self-weight of the slabs directly depends on the shape and number of hollows. An increase in the hollowness of a slab significantly reduces the load caused by self-weight. This allows increasing the estimated length of the slab under the same payload. An increase in the amount of hollows of the slab changes the stiffness of the slab cross-section that has a direct impact on slab deflection. Considering the shape of the slab cross-section, theoretical calculations of the flexural capacity and deflection of experimental slabs were made. The design of a new type of slabs and variations in different parameters of the slab experience difficulties in conducting a large amount of experimental tests. Therefore, the initial analysis may apply to numerical simulation. The paper describes the principles of designing a numerical model. The calculations were made using DIANA software. The stiffness and flexural capacity of the hollow slabs were established employing numerical simulation compared to the results of experimental investigations. The findings indicate that numerical simulation can be applied for analysing the stress state of the examined structures.
28
Wei, Liu, and T. F. Fwa. "Closed-Form, Six-Slab, Thick-Plate Solution for Analysis of Edge Slab of Concrete Pavement." Transportation Research Record: Journal of the Transportation Research Board 1919, no. 1 (January 2005): 2–15. http://dx.doi.org/10.1177/0361198105191900101.
Full textAbstract:
The development and application of a theoretical closed-form solution of a six-slab, thick-plate model for the structural design and analysis of an edge slab in jointed concrete pavement subjected to vertical loads are described. The jointed concrete pavement system is idealized as a six-slab system resting on a Winkler foundation. The six slabs are arranged in two rows with three slabs in each row. The loaded slab of interest is represented by a middle slab with five surrounding slabs to consider the effects of jointed pavement system. Fundamental equations of the proposed model were derived from thick-plate theory. Solutions of the fundamental equations were obtained by superposition of the solutions of appropriate elemental slabs. The validity of the proposed solutions was checked against finite element solutions. The six-slab model was applied to analyze the critical stresses and deflections of an edge slab under the following three loading conditions: interior, edge, and corner loadings. Comparisons of the computed critical stresses and deflections were made with Westergaard's solutions. Westergaard's solutions were found to overestimate the maximum bending stresses and deflections for large slabs but to tend to underestimate these pavement responses for small slabs. The likelihood of underestimation by Westergaard's solutions also increased as the load transfer efficiency of pavement joints fell.
29
Han, Zebin, Wenjun Qu, and Peng Zhu. "Research on Hybrid FRP–Steel-Reinforced Concrete Slabs under Blast Load." Buildings 13, no. 4 (April 18, 2023): 1058. http://dx.doi.org/10.3390/buildings13041058.
Full textAbstract:
The service environment of civil air defense engineering structures is relatively harsh, and the corrosion of steel bars is the main reason for reducing the durability of concrete structures in civil air defense engineering. A hybrid FRP–steel-reinforced concrete (hybrid-RC) structure has excellent durability. Therefore, it is a good choice to apply hybrid-RC to civil air defense engineering structures. In order to study the blast resistance of hybrid-RC structures, close blast and contact blast experiments were carried out on hybrid-RC slabs, steel-reinforced concrete (SRC) slabs and GFRP-reinforced concrete (GRC) slabs. For the close blast experiment, the steel reinforcement in the SRC slab first entered the plasticity stage, whereas the GFRP reinforcement in the hybrid-RC slab was in the elastic stage under the close blast. Therefore, the capacity to dissipate energy through the vibration in the hybrid-RC slab was better than that of the SRC slab. The residual deformation in the hybrid-RC slab after the close blast experiment was smaller than that of the SRC slab. The Blast Recovery Index (BRI) was introduced to evaluate the recovery capacity of the concrete slab after the close blast, and damage assessment criteria for the hybrid-RC slabs were proposed according to the maximum support rotation θm and BRI. There was little difference in the size of the local damage in the hybrid-RC slab and the SRC slab under the contact blast. However, since the GFRP reinforcement was still in the elastic stage and the steel reinforcement was plastic after the contact blast, the ratio of the residual bearing capacity to the original bearing capacity in the hybrid-RC concrete slab would be larger than that of the SRC slab. The prediction formula for the top face diameter D and blasting depth L of the hybrid-RC slab was obtained through dimensionless analysis. This research can provide a reference for the anti-blast design of hybrid-RC slabs.
30
Li, Bing, Zhengshang Li, Zhijun Chen, Zhoulin Yang, and Yang Zhang. "Experimental Study on the Structural Performance of Reinforced Truss Concrete Composite Slabs during and after Fire." Buildings 13, no. 7 (June 26, 2023): 1615. http://dx.doi.org/10.3390/buildings13071615.
Full textAbstract:
Standard fire resistance tests and post-fire tests on residual mechanical properties were carried out on two four-edge simply supported reinforced truss concrete two-way composite slabs with wide seam splicing (“integral seam”) and close seam splicing (“separated seam”), and the effects of the different splicing forms on the mechanical properties of the reinforced truss concrete composite slabs during and after exposure to high temperatures were explored. The results indicate that there are significant differences in terms of crack developments, moisture loss times on the slab surface, spalling characteristics of the bottom of the slab and cross-section temperature gradients of concrete and steel reinforcement along the thickness direction between the wide seam spliced reinforced truss concrete composite two-way slab (referred to as “S1 composite slab”) and the close seam spliced reinforced truss concrete composite two-way slab (referred to as “S2 composite slab”) in the fire test. This is mainly due to differences in the splicing forms and structural measures of the prefabricated base slabs at joints, which led to changes in the heat transfer path at the joints. As the temperature at the close seam can be released quickly, the stiffness recovery of the S2 composite slab is significantly greater than the stiffness weakening due to the thermal hysteresis of the concrete, so the deflection of the S2 composite slab recovers immediately after the fire stops. Overall, both the S1 and S2 composite slabs exhibit two-way high temperature deformation characteristics. The post-fire residual static load tests show that the static load-carrying capacity of the S1 composite slab is 12.08% higher than that of the S2 composite slab and the ultimate displacement is 8.74% lower than that of the S2 composite slab. It is appropriate to calculate the residual load capacities of the S1 and S2 composite slabs after the fire as a one-way slab.
31
Flores Bastidas, Camilo, Constanza Lucia Flores Bastidas, Jun Ichiro Giorgos Tsutsumi, and Caori Patricia Takeuchi. "Approach to the Load Resistance in Two Kinds of Bamboo Reinforced Concrete Slab." Advanced Materials Research 261-263 (May 2011): 459–63. http://dx.doi.org/10.4028/www.scientific.net/amr.261-263.459.
Full textAbstract:
Steel reinforced concrete is generally used in houses structure elements. However bamboo strength properties similarly to the wood, make it an alternative concrete composite material. Load test were performed in two kinds of bamboo guadua concrete reinforced composite slabs. During the tests the slabs functioned as domestic roofing-flooring in standing houses, the slab systems tested were bamboo stem covered slab and stem free slab. Two different tests were designed to measure the deflection in the middle of the composite slab and along a single bamboo stem. In three different slab sizes and after replications, no deflection under the applied load was recorded. Therefore, bamboo composite slabs without steel reinforcing seem likely to be used in long lasting houses for middle and high class dwellings in Colombia.
32
Zhao, Xin, Dan Dan Kong, Zhi Wei Zhang, and Mai Wu. "Study on Mechanical Behaviors of New Reinforced Concrete Hollow Floor Slab." Applied Mechanics and Materials 94-96 (September 2011): 1018–21. http://dx.doi.org/10.4028/www.scientific.net/amm.94-96.1018.
Full textAbstract:
In this paper a new type of reinforced concrete four-way rib hollow slab was proposed by the authors first. Further in order to research on the mechanical properties of the new floor slab the other two common slabs were compared with the new one, that was two-way rib hollow slab and solid slab. The rational finite element (FE) models of the three kinds of slabs supported by four corner columns were built up respectively by ANSYS. The deflection and stress of the three kinds of slabs under three load cases were calculated separately, on the basis of which thorough comparisons and analysis were carried out. The study results showed that the new reinforced concrete four-way rib hollow floor slab has superior mechanical properties.
33
Okoroafor, S. U., P. C. Anyadiegwu, and O. O. Okpo. "Bending strength characteristics of sawdust- crete laminated composite slab." Nigerian Journal of Technology 41, no. 3 (November 2, 2022): 419–28. http://dx.doi.org/10.4314/njt.v41i3.1.
Full textAbstract:
This paper presents the bending characteristics of sawdust-crete laminated composite slab. The materials used in the laboratory experiments include: Ordinary Portland Cement, river sand, gravel, sawdust, plywood, nails, reinforcement bars, stirrups and water. Manual mixing method was adopted and all sawdust-crete ingredients were batched by weight. A total of 48 slabs of size 1200mm x 1000mm x 100mm, 1200mm x 1000mm x 125mm, 1200mm x 1000mm x 150mm and 1200mm x 100mm x 175mm were cast for flexural strength from the mix ratios 0.75:1:2:2 and 0.75:1:3:3. Out of the 48 slabs cast, 32 were produced from sawdust-crete laminated composite (with 12.5mm and 20mm as the thickness of plywood for the laminate), 8 were produced from normal concrete ingredients (coarse aggregates, fine aggregates, cement and water) with 10mm rebar and mix ratio of 0.45:1:2:4. The remaining 8 slabs were made from plain sawdust-crete with mix ratio of 0.75:1:3:3. During the experiment, the maximum deflection for the slab was observed to occur at the slab with size 1200mm x 1000mm x 100mm no matter the core content used to produce the slab while the minimum deflection occurs at the size 1200mm x 1000mm x 175mm. The deflection of slab decreases with increase in slab thickness while flexural strength increases with increase in slab thickness. The flexural strength results of slab were compared by percentage difference and the results shows that there is significant difference between the two sets of slabs. Also, by comparing the results of plain sawdust-crete slab to that of sawdust-crete laminated composite slab, the result show that laminates with plywood increases flexural strength up to 68.4%. Conclusively, laminated sawdust-crete can be used for slabs that is not carrying too much load like residential houses.
34
Ahmad, Omar. "Financial comparative study between post-tensioned and reinforced concrete flat slab." International Journal of Advanced Engineering, Sciences and Applications 3, no. 1 (January 31, 2022): 1–6. http://dx.doi.org/10.47346/ijaesa.v3i1.67.
Full textAbstract:
As for today, post-tensioned slabs gained much popularity and started to be widely used among construction companies all around the world. As we refer to the structural members, we acknowledge that the price of the slab is much higher in comparison to the other structural members like columns, beams, or foundation in accordance to the amount of steel and concrete in it. A comparative study has been done between post-tensioned, and reinforced concrete flat slab to compare how much each slab cost. It describes that since the post-tension slabs are thinner and it provides fewer columns, so the amount of concrete required is less than the required amount in a flat slab. Special steel tendons that are used in post-tensioned slabs will be stretched by a hydraulic jack after the casting of concrete, and these tendons have an effect in reducing the reinforcement steel bars. Although tendons are used only in post-tension slabs, the amount of steel used in it is less compared to flat slabs. Furthermore, the contractor work cost differs from doing the post-tensioned slab and flat slab. The study had been done by comparing the amount of concrete, steel and contractor work cost. The results obtained from the comparative study between post-tension slabs and reinforcement concrete flat slabs indicate that post-tensioned slabs are cheaper.
35
Chung, Joo Hong, Hyun Ki Choi, Seung Chang Lee, and Chang Sik Choi. "Punching Shear Strength of Biaxial Hollow Slab with Donut Type Hollow Sphere." Key Engineering Materials 452-453 (November 2010): 777–80. http://dx.doi.org/10.4028/www.scientific.net/kem.452-453.777.
Full textAbstract:
This paper presents the punching shear capacities of biaxial hollow slab with donut type hollow sphere. Recently, various types of slab systems which can reduce self-weight of slabs have been studied as the height and width of building structures rapidly increase. A biaxial hollow slab system is widely known as one of the effective slab system which can reduce self-weight of slab. According to previous studies, the hollow slab has weakness in slab-column connection. In addition, the present code does not provide a clear computation method for the punching shear strength of hollow slab. In this study, the special type of cage was used to improve punching shear capacities and fix the hollow spheres in critical section. To verify the punching shear capacities of this biaxial hollow slab, punching shear tests were performed. Four test specimens were used for test parameters. One was conventional RC slab and three were hollow slabs. The test parameter was the areas of critical section which were determined by the number of hollow spheres in critical section.
36
Zhang, Jing Shu, Huan Huan Nie, Yuan Long Yang, and Yuan Yao. "Research and Application of Pre-Stressed Concrete Composite Slabs." Applied Mechanics and Materials 166-169 (May 2012): 131–39. http://dx.doi.org/10.4028/www.scientific.net/amm.166-169.131.
Full textAbstract:
The pre-stressed concrete composite slab, which combines the advantages of cast-in-place slabs and precast slabs, has promising development prospects. In the paper, according to structural integrity, bond performance, sound insulation, thermal preservation and construction techniques, four categories composite slab, such as the composite slab with flat bottom panel (including the composite slab with bar truss reinforced precast concrete bottom panel), the concrete composite slab with precast ribbed panel, the composite slab with hollow bottom panel and the composite slab with sandwich bottom panel are studied. The composite slab with flat bottom panel has poor structural integrity, and its bond performance and crack resistance of edge joint details need to be improved; the composite slab with bar truss reinforced precast concrete bottom panel has enough bond force, but its storage and transportation are inconvenient; the concrete composite slab with precast ribbed panel has good structural integrity and convenient construction procedure; the composite slab with hollow bottom panel and the composite slab with sandwich bottom panel have functions of sound insulation and thermal preservation, however they are inadequacy to resist bending moment and have complex construction procedure. The concrete composite slab with precast ribbed panel is provided with good mechanical behavior, economy and practicability, and is worth further researching and promoting.
37
Makki, Ragheed, Haider Al-Katib, and Ahmed Alalikhan. "Load-defl ection behaviour of hybrid concrete flat slab." Przegląd Naukowy Inżynieria i Kształtowanie Środowiska 28, no. 4 (December 29, 2019): 516–25. http://dx.doi.org/10.22630/pniks.2019.28.4.47.
Full textAbstract:
Due to the important role of high strength concrete in the structural systems, present work focuses on the use of this material as a strengthening technique incorporating with the normal strength concrete in flat slab system. Eight simply supported flat slab models with (1,000 × 1,000 × 120 mm) dimensions are investigated based on three groups including normal strength concrete and high strength concrete. The first group represents models containing of two flat slabs fully with one type of concrete; NSC and HSC as control flat slab. The second and third groups consist of six flat slabs as hybrid flat slabs of two layer of concrete with different thicknesses. Concrete mixture HSC was used in tension zone in three hybrid flat slabs (second group) with three thicknesses (30, 60 and 90 mm), while the remaining three hybrid flat slabs (third group) was used the HSC in compression zone with the same previous thicknesses. The experimental results shown that the ultimate load increased about (19.4%) when HSC was used fully (hH / h = 1) instead of using NSC in the control flat slab (NSC slab). The hybrid flat slabs with use HSC in compression zone showed higher in cracking and ultimate flexural loads compared with those of the hybrid flat slabs with use HSC in tension zone and also were stiffer in load-defl ection curve with the hybrid flat slabs with HSC in tension zone, also the hybrid flat slabs showed an improvement in the cracking load and ultimate flexural load when increasing the thickness of the HSC layer (hH / h) in both tension and compression zone as compared to control flat slab (NSC slab).
38
Zhou, Hai Long, Xiang Dong Shen, and Tian Yu Zhang. "Calculation of Load Lateral Distribution for Hinged Slab Bridge with Different Stiffness between Outside Slabs and Inside Slabs." Applied Mechanics and Materials 178-181 (May 2012): 2530–34. http://dx.doi.org/10.4028/www.scientific.net/amm.178-181.2530.
Full textAbstract:
Based the hinged slab bridge theory and fundamental of structural mechanics, calculation formulas of load lateral distribution are deduced for hinged slab bridge with different rigidity between outside slabs and inside slabs, which make the hinged slab theory more perfect. Finally, a practical example is calculated and its results are compared with the results calculated by Equivalent Stiffness Method.
39
Pandey, Manish Kumar. "Seismic Response of Large span slab in Horizontal Setback Building: A Review." International Journal for Research in Applied Science and Engineering Technology 9, no. 10 (October 31, 2021): 508–14. http://dx.doi.org/10.22214/ijraset.2021.38452.
Full textAbstract:
Abstract: The demand of multistory Building is increases day by day. The residential plus commercial building predominantly used for the need of large span. The large span is needed for Flat slab, Waffle slabs & ribbed slab stands as an excellent option for architects when larger spans in a building has to be covered with the least possible number of columns. The use of different types slabs are evolving as a new trend and are becoming a big challenge for structural engineers. Therefore it is necessary to study about its structural behavior. The paper is review the behavior of different types slab for large span type of building. Final aim to gets the suitable type of slab for large span for effective manner. It is found that very less work is taken setback building with large span, it is required to analysis on the setback building with large span. Keywords: Flat slab, Waffle slabs, ribbed slab, multistory Building, large span.
40
Liu, Xiaowen, Claire A. Currie, and Lara S. Wagner. "Cooling of the continental plate during flat-slab subduction." Geosphere 18, no. 1 (December 22, 2021): 49–68. http://dx.doi.org/10.1130/ges02402.1.
Full textAbstract:
Abstract Most flat-slab subduction regions are marked by an absence of arc volcanism, which is consistent with closure of the hot mantle wedge as the subducting plate flattens below the continent. Farther inland, low surface heat flow is observed, which is generally attributed to cooling of the continent by the underlying flat slab. However, modern flat slabs have only been in place for <20 Ma, and it is unclear whether there has been sufficient time for cooling to occur. We use numerical models to assess temporal variations in continental thermal structure during flat-slab subduction. Our models show that the flat slab leads to continental cooling on timescales of tens of millions of years. Cool slab temperatures must diffuse through the continental lithosphere, resulting in a delay between slab emplacement and surface cooling. Therefore, the timescales primarily depend on the flat-slab depth with shallower slabs resulting in shorter timescales. The magnitude of cooling increases for a shallow or long-lived flat slab, old subducting plate, and fast convergence rates. For regions with flat slabs at 45–70 km depth (e.g., Mexico and Peru), shallow continental cooling initiates 5–10 Ma after slab emplacement, and low surface heat flow in these regions is largely explained by the presence of the flat slab. However, for the Pampean region in Chile, with an ~100-km-deep slab, our models predict that conductive cooling has not yet affected the surface heat flow. The low heat flow observed requires additional processes such as advective cooling from the infiltration of fluids released through dehydration of the flat slab.
41
Lowe, Maximilian, Jörg Ebbing, Amr El-Sharkawy, and Thomas Meier. "Gravity effect of Alpine slab segments based on geophysical and petrological modelling." Solid Earth 12, no. 3 (March 19, 2021): 691–711. http://dx.doi.org/10.5194/se-12-691-2021.
Full textAbstract:
Abstract. In this study, we present an estimate of the gravity signal of the slabs beneath the Alpine mountain belt. Estimates of the gravity effect of the subducting slabs are often omitted or simplified in crustal-scale models. The related signal is calculated here for alternative slab configurations at near-surface height and at a satellite altitude of 225 km. We apply three different modelling approaches in order to estimate the gravity signal from the subducting slab segments: (i) direct conversion of upper mantle seismic velocities to density distribution, which are then forward calculated to obtain the gravity signal; (ii) definition of slab geometries based on seismic crustal thickness and high-resolution upper mantle tomography for two competing slab configurations – the geometries are then forward calculated by assigning a constant density contrast and slab thickness; (iii) accounting for compositional and thermal variations with depth within the predefined slab geometry. Forward calculations predict a gravity signal of up to 40 mGal for the Alpine slab configuration. Significant differences in the gravity anomaly patterns are visible for different slab geometries in the near-surface gravity field. However, different contributing slab segments are not easily separated, especially at satellite altitude. Our results demonstrate that future studies addressing the lithospheric structure of the Alps should have to account for the subducting slabs in order to provide a meaningful representation of the geodynamic complex Alpine area.
42
Muhamad Khairussaleh, N. A., R. Omar, S. Mat Aris, M. F. Mohd Nor, M. A. Mohd Saidi, and N. M. A. Nik Mohd Mahari. "Flexural Behaviour of the Two-Way Spanning Reinforced Concrete Slab Using Spherical Plastic Bubble Balls." IOP Conference Series: Earth and Environmental Science 1140, no. 1 (February 1, 2023): 012016. http://dx.doi.org/10.1088/1755-1315/1140/1/012016.
Full textAbstract:
Abstract The use of conventional reinforced concrete in the construction industry increases each year, especially in developing countries. However, the concrete content, particularly cement production contributed to the greenhouse gas emission subsequently increase to climate change. Thus, the reinforced concrete slab containing high-density polyethene (HDPE) hollow spherical plastic bubble balls also known as bubble deck slabs were introduced for sustainable construction. This type of slab forms a slab that has less concrete volume compared to the normal solid reinforced concrete slab. Although this unique system can facilitate up to a 50% longer span compared to the conventional reinforced concrete solid slab, yet, it can cause the performance of the slab structure such as flexural and shear capacity may be affected due to the thirty to forty per cent of fewer concrete volumes. Hence, this paper studies the comparison of the performance of the two-way supported slabs; reinforced bubble deck slab and normal solid reinforced concrete slab after being subjected to the area loading. The square slabs are 1200mm by 1200mm in width and length with a thickness of 235mm. The investigations of the experiments included flexural strength, bending stiffness and load-deflection behaviour due to the impact of the area loading. Also, the crack propagation and crack pattern which differs also was shown for each type of slab system, especially in shear strength.
43
A. Alwash, Nameer, and Fatimah H. Naser Al-Mamoori. "Behavior of The RC Slab-Beam System Using Self Compacting Concrete." International Journal of Engineering & Technology 7, no. 4.20 (November 28, 2018): 507. http://dx.doi.org/10.14419/ijet.v7i4.20.26252.
Full textAbstract:
The present study includes an experimental investigation of the behavior of square reinforced concrete slabs. These slabs are with and without edge beams under uniformly distributed load with corner supports using two types of self compacting concrete (SCC), the first type of SCC incorporated limestone filler and the other was without filler, the results obtained are compared with those obtained from conventional concrete (CC).The experimental program consists of testing nine square slab samples. Three of these slab samples are flat in shape with panel dimensions of 1050×1050×50 mm depth. The others three slab samples are of the same outer dimensions with surrounding edge beams of depth to slab thickness equal 100/50 and 100 mm width. The last three slab samples are similar to the former slab-beam systems but with increasing the depth of edge beams by 50%.In general, for a specified flat plate panel, the ultimate load carrying capacity can be increased, if the panel is restricted by four surrounding beams. The slab-beam samples with surrounding beams of depth to slab thickness equal to 3 showed greater ultimate load capacity by about 79.37%, 52% and 97.82% when compared with the corresponding flat slabs samples produced using CC, SCC with and without filler, respectively.
44
Wang, Lei, and Hong Ya Zhang. "Summary of Study on Composite Concrete Slabs." Applied Mechanics and Materials 351-352 (August 2013): 695–98. http://dx.doi.org/10.4028/www.scientific.net/amm.351-352.695.
Full textAbstract:
Reinforced Concrete Slab is one of the important types of composite structure, About the concrete laminated slab of the research and the engineering application are summarized, Point out that the characteristics of Composite Concrete Slabs, the application and development of the laminated slab of recent advances at home and abroad, and look into the future of the Composite Concrete Slabs research.
45
Al-Ansari, Mohammed Salem, and Muhammad Shekaib Afzal. "Structural analysis and design of irregular shaped reinforced concrete slabs using a simplified design method." Journal of Structural Engineering & Applied Mechanics 3, no. 4 (December 31, 2020): 276–88. http://dx.doi.org/10.31462/jseam.2020.04276288.
Full textAbstract:
This paper presents a simplified method to analyze and design the irregular reinforced concrete slabs based on structural safety and economy. The triangular, trapezoidal, and curved slab sections are selected in this study to be analyzed and designed using a simplified design method approach (SDM) as these sections are the most common type of irregular slab sections used in the construction industry. Flexural design formulas for triangular and curved slabs are derived based on the theoretical principles of plate and yield line theories and ACI building code of design constraints. Numerical examples are presented in this study to illustrate the method capability of designing the most commonly used irregular slabs sections. The complete design of four triangular slabs (TS-1 to TS-4) and four curved slabs (CS-1 to CS-4) is provided in this study. Besides, the required equivalent (triangular and rectangular) shaped sections are provided to deal with irregular trapezoidal slab section. The selected irregular slab sections (triangular and curved slab sections) are also analyzed and designed using the computer software (SAFE) and the results obtained are compared with the numerical solutions. The percentage difference of the simplified method with the finite element software (SAFE) ranges from 4% to 12%. The results obtained for all the selected irregular shaped slab sections indicates that the SDM is a good and quick approach to design irregular (triangular and curved) slab sections.
46
Dadzie, Donald Kwabena, and A. K. Kaliluthin. "Implications of Palm Kernel Shell-Filled Plastic Bottles on the Structural Behavior of Concrete Slab." Civil Engineering Journal 9, no. 3 (March 1, 2023): 731–51. http://dx.doi.org/10.28991/cej-2023-09-03-016.
Full textAbstract:
The implications of palm kernel shell (PKS)-filled plastic bottles on the structural behaviour of concrete slabs were carried out by comparing the flexural performance of conventional solid concrete slabs to concrete slabs incorporated with plastic bottles filled with palm kernel shells and placed vertically, horizontally, and diagonally at the neutral axis of the slab as per Bubble Deck Slab technology. One-way slab specimens of size 700 × 300 × 150 mm thick were produced and subjected to a four-point flexural load test. Findings from the study indicated that: (1) The PKS-filled bottle slabs deflected more than the conventional solid slab, hence making them more flexible than the conventional slabs and, as such, giving the occupants enough time to evacuate. (2) The flexural strengths of the PKS-filled bottle slabs exceeded those of conventional slabs by 18.3% and 10.9%, respectively, for five and ten percentages of the volume of slab concrete occupied. (3) The condition of the PKS, either dry or saturated, coupled with the bottle arrangement (either vertical, horizontal, or diagonal), does not, however, cause any significant change to the performance of the PKS filled bottle slabs in terms of load carrying capacity, deflection, and strength. Doi: 10.28991/CEJ-2023-09-03-016 Full Text: PDF
47
Guo, Gaoran, Xuhao Cui, and Bowen Du. "Random-Forest Machine Learning Approach for High-Speed Railway Track Slab Deformation Identification Using Track-Side Vibration Monitoring." Applied Sciences 11, no. 11 (May 22, 2021): 4756. http://dx.doi.org/10.3390/app11114756.
Full textAbstract:
High-speed railways (HSRs) are established all over the world owing to their advantages of high speed, ride comfort, and low vibration and noise. A ballastless track slab is a crucial part of the HSR, and its working condition directly affects the safe operation of the train. With increasing train operation time, track slabs suffer from various defects such as track slab warping and arching as well as interlayer disengagement defect. These defects will eventually lead to the deformation of track slabs and thus jeopardize safe train operation. Therefore, it is important to monitor the condition of ballastless track slabs and identify their defects. This paper proposes a method for monitoring track slab deformation using fiber optic sensing technology and an intelligent method for identifying track slab deformation using the random-forest model. The results show that track-side monitoring can effectively capture the vibration signals caused by train vibration, track slab deformation, noise, and environmental vibration. The proposed intelligent algorithm can identify track slab deformation effectively, and the recognition rate can reach 96.09%. This paper provides new methods for track slab deformation monitoring and intelligent identification.
48
Sun, Xiu Shan, Ying Hua Liu, Zhang Zhi Cen, and Dong Ping Fang. "Numerical Simulation of Deformation and Strength of Reinforced Concrete Slabs under Thermal-Mechanical Loads." Key Engineering Materials 353-358 (September 2007): 2676–80. http://dx.doi.org/10.4028/www.scientific.net/kem.353-358.2676.
Full textAbstract:
In this paper, full-scale reinforced concrete slabs are analyzed under thermal-mechanical loads in fire conditions. The rectangular one-way slabs including a simply supported slab and a three-span continuous slab are concerned in the analysis. Finite element simulation is carried out by using the ABAQUS program to evaluate the non-uniform temperature distributions in thickness of the slabs and to analyze the deformation and stress redistribution of the slabs at elevated temperatures. Sequentially coupled thermal and structural analyses are performed to simulate the responses of the slabs in fire conditions. Deformation and strength of the slabs under thermal and mechanical loads are discussed. The numerical results are compared with the experimental ones and good agreements are observed. The analysis results show that the main reinforcement ratio has significant effects on the deformation and strength of the slabs at elevated temperatures and the three-span continuous slab has better performance of fire-resistance than the simply supported slab.
49
Razaqpur, A. Ghani, Ettore Contestabile, and Ahmed Tolba. "Experimental study of the strength and deformations of carbon fibre reinforced polymer (CFRP) retrofitted reinforced concrete slabs under blast loadThis article is one of a selection of papers published in the Special Issue on Blast Engineering." Canadian Journal of Civil Engineering 36, no. 8 (August 2009): 1366–77. http://dx.doi.org/10.1139/l09-002.
Full textAbstract:
The blast response and ultimate resistance of reinforced concrete slabs externally strengthened with carbon fibre reinforced polymer (CFRP) laminates were investigated. Five square slab specimens, 1 m on a side, were retrofitted with 500 mm wide CFRP laminates bonded to their top and bottom surfaces. Another four nominally identical unretrofitted slabs were used as control specimens. Four of the retrofitted and the four control slabs were first subjected to the detonation of either 22.4 or 33.4 kg of explosive at a stand-off distance of 3.0 m. For reference, the fifth retrofitted slab was only statically tested to failure. Blast pressures and impulses and slab deformations were measured. After exposure to the blast, the slabs that were not completely damaged were statically tested to failure. Overall the retrofitted slabs performed better than the control slabs, but one retrofitted slab completely failed under the blast load while none of the control slabs experienced complete failure under similar load.
50
Lyu, Tianyang, Zhiyuan Zhu, and Benjun Wu. "Subducting slab morphology and mantle transition zone upwelling in double-slab subduction models with inward-dipping directions." Geophysical Journal International 218, no. 3 (June 14, 2019): 2089–105. http://dx.doi.org/10.1093/gji/ggz268.
Full textAbstract:
SUMMARY Lithospheric plates on the Earth's surface interact with each other, producing distinctive structures comprising two descending slabs. Double-slab subduction with inward-dipping directions represents an important multiplate system that is not yet well understood. This paper presents 2-D numerical models that investigate the dynamic process of double-slab subduction with inward dipping, focussing on slab geometry and mantle transition zone upwelling flow. This unique double-slab configuration limits trench motion and causes steep downward slab movement, thus forming fold piles in the lower mantle and driving upward mantle flow between the slabs. The model results show the effects of lithospheric plate properties and lower-mantle viscosity on subducting plate kinematics, overriding plate stress and upward mantle flow beneath the overriding plate. Appropriate lower-mantle strength (such as an upper–lower mantle viscosity increase with a factor of 200) allows slabs to penetrate into the lower mantle with periodical buckling. While varying the length and thickness of a long overriding plate (≥2500) does not have a substantial effect on slab geometry, its viscosity has a marked impact on slab evolution and mantle flow pattern. When the overriding plate is strong, slabs exhibit an overturned geometry and hesitate to fold. Mantle transition zone upwelling velocity depends on the speed of descending slabs. The downward velocity of slabs with a large negative buoyancy (caused by thickness or density) is very fast, inducing a significant transition zone upwelling flow. A stiff slab slowly descends into the deep mantle, causing a small upward flow in the transition zone. In addition, the temporal variation of mantle upwelling velocity shows strong correlation with the evolution of slab folding geometry. In the double subduction system with inward-dipping directions, the mantle transition zone upwelling exhibits oscillatory rise with time. During the backward-folding stage, upwelling velocity reaches its local maximum. Our results provide new insights into the deep mantle source of intraplate volcanism in a three-plate interaction system such as the Southeast Asia region.