Papers by Keyword: Reinforced Concrete Slab

Abstract: The influence of modeling the support of floor slabs on forces and deformations is shown. In slabs freely supported on the walls, the corner zones move upwards. In slabs that are partially pinched into the walls, negative bending moments occur. The degree of pinching and separation of the corner zones depends on several factors. The article shows how to take into account these factors in the design.

Abstract: This paper investigates the finite element modelling of the temperature distributions of reinforced concrete slab using a general purpose non-linear finite-element program, ABAQUS. The reinforced concrete slab is tested under exposure to designed fire in order to validate the shell element in in the ABAQUS program. The modelling results showed agreement with the fire test and it demonstrated that the ABAQUS shell element can be used to predict fire behaviour within reinforced concrete slab in elevated temperature conditions.

Abstract: This study applies the nonlinear finite element analysis software LS-DYNA to conduct a numerical simulation of damage mode of reinforced concrete slab under complex boundary condition subjected to air blast load. The factors affecting damage model of reinforced concrete slab, standoff distance and explosives location, were analyzed. The results show that: With the increase of the standoff distance, the failure mode of RC slab gradually changes from localized punching failure to shear failure at the support. With the location for explosive changing from the center of RC slab to the beam plate combination, the failure mode of RC slabs gradually changes from localized punching failure to bending-shear failure under close-in blast loading.

Abstract: We analyzed the rectangular slab with four sides supported, respectively elastic and plastic methods of calculation the slab. Generally considered l₂/l₁≤2 calculated as the two-way slab, 2< l₂/l₁<3 should be calculated as the two -way slab, however l₂/l₁≥3 calculated as one-way slab, consider these provisions is not reasonable, analysis shows, if using elastic or plasticity theory analysis, l₂/l₁ <3, or l₂/l₁ <4 as the two-way slab. Otherwise, it is one-way slab. Reasonable distinction between one-way slab and two-way slab are meaningful, not only simplifies the calculation, but also makes the design economical, safe and reliable.

Abstract: Reinforced concrete panels were tested explosion for reinforced concrete slab in the dynamic response under blast loading. Dimensions of 1300mm×1300mm×50mm plates under different reinforcement ratio were designed. Explosion test was carried out for three different batches of reinforcement ratio reinforced concrete slab in the explosion simulator. The load was calculated using empirical formulas. Blast loading time curve was obtained by the explosion test and the correctness of the numerical simulation method was verified. The results indicate that reinforced concrete slab under blast loading is different from static damage destruction. Diagonal cracks appear on plat under the blast loading destroyed. When the peak load is large, a large square cracks plate was appeared in the middle of the plate and accompanied diagonal cracks. When the peak load is small, diagonal cracks develop fully, square cracks were smaller.

Abstract: Concepts of remedial treatments of historic buildings using ventilated floors, with a few exceptions, are with considerable popularity preferred by the representatives of monument protection. The fact that they require small interventions in the masonry is of great benefit for compliance with the methodology of cultural heritage protection, as is the fact that such interventions do not compromise the structural analysis of buildings. These concepts have gained great popularity also because they can be considered kind of a "return" to historical example. With these technologies we return to the methods and principles that the ancient Egyptians were already familiar with. The paradox is that these methods are used for many centuries, until today they are only proposed on the basis of empiricism. In this article two different underfloor ventilation systems are compared using CFD simulation.

Abstract: The damage and failure of reinforced concrete (RC) slabs under blast loadings may cause significant hazards for frame systems even progressive collapse of whole structures. The numerical simulation of one-way RC slabs using the finite element explicit code LS-DYNA to estimate the dynamic response and failure mode of one-way RC slabs .Blast loadings are imposed on the top surface of slabs using a blast model based on conwep algorithm. Concrete was modeled using a concrete damage constitutive model considering strain rate effect, and reinforcement was modeled using a elastoplastic material type with kinematic hardening and strain rate effect. The numerical model is introduced in details and adopted to simulate the dynamic responses of RC slabs in reference test. The numerical model can match well with the test data, and thus the proposed numerical model can be considered as a valuable tool in assessing the deformation or failure mechanism and predicting the dynamic responses of one-way RC slabs subjected to blast loadings.

Abstract: This paper presents the latest developments of a simple method used to determine the ultimate load of two-way simply supported reinforced concrete slabs. Based on the reinforcement ratio, two failure criteria are proposed in the paper. The effectiveness of the developed model is validated through satisfactory comparison with from test results.

Abstract: The influence of the structure parameters on the anti-impact performances of the reinforced concrete slab is studied in the article. The reinforced concrete model is established by using ANSYS 13.0/LS-DYNA and nonlinear finite element theory and the parameterized modeling is achieved. The results show that the increase of the thickness of the slab and the steel bar diameter result in the enhancement of impact resistant capability of the slab; a appropriate quantity of reinforcement is significant; Increasing the concrete strength has a distinct impact on the slab’s impact resistance when using relatively low strength concrete. However the influence becomes weak after the concrete strength comes to C60 and higher. The fruits are useful to the designing of reinforced concrete slabs.

Abstract: There are no clear design standards for the reinforcements or concealed beams under partitions in reinforced concrete slabs which often appear in reinforced-concrete residential buildings. Designers, in most cases, have to rely on engineering experiences after a simple calculation to design such reinforcements or concealed beams. In this paper, we built a finite element model of such reinforced concrete slabs in SAP2000. The element for the plates was layered shell element. By changing the span , thickness and boundary constraints of the plate, the materials of the partition , the diameter of the reinforcements to analyze the force of the plate. Based on results analyzed, we discuss the internal forces of such plates, and offer suggestions for the selection of partitions and design of reinforcements.