الفهرس 
LITERATURE SURVEYOnly 14 pages are availabe for public view
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Abstract
High Performance Concrete (HPC) is one such new material that has a major improvement over conventional concrete, but its behavior is still in the process of being defined. Pervious researches indicated that the mix proportions can be adjusted to produce high compressive and tensile strength HPC with strain softening behavior. These enhanced properties make HPC considered as a promising construction material especially in shear-critical slabs. Most of previous studies on HPC have focused on special concrete materials with characteristics that differ from those of conventional concrete at the material level. However, few experimental test results are available on the shear behaviour and capacity of HPC slabs at the structural level. The punching characteristics of HPC slabs is still poorly understood.In this study, large scale experimental program consisting of eleven specimens has been conducted. The test specimens were categorized into three groups according to the studied parameters. These groups discussed the following items; (1) the comparison of normal strength concrete (NSC),fiber reinforced concrete (FRC), and HPC slabs as well as the role of polypropylene fibers (PP fibers) in improving the punching shear strength,(2) The effect of the boundary conditions on the punching shear strength and (3) the influence of applying unbalanced moments on the punching behavior. In all the experiments, the steel-strains, deflections, crack patterns and ultimate loads were recorded.Expanded numerical program is performed using the finite element software ANSYS-V19.2 in order to widely study the effect of relative parameters on the punching shear strength. These parameters include the effect of changing the location of the load, the effect of tension and compression reinforcement, the effect of compressive strength, the effect of load aspect ratio, size effect and the effect of the load size.A new single proposed equation based on the experimental results and the finite element case studies was developed accounting the main parameters affecting the punching strength. Furthermore, the proposed equation was validated and compared against all case studies as well as well as the experimental work of the pervious researches. Finally, the whole data were used to train, validate and test a neural network that can predict the punching capacity of slabs. The neural networks were found to be a good tool to predict punching capacity of slabs.