الفهرس 
CHAPTER 1 INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Construction on foundation subsoils that contain weak regions or subterranean cavities creates problems with the stability and tilt of the superstructures. The extent of the danger of underground voids underneath structures varies depending on their sizes and locations from the building foundations. The previous studies in the literature mainly focused on the behavior of footings rested on soil with voids without considering the soil-structure interaction (SSI) and the nonlinear behavior of the concrete superstructure. The author has conducted analysis of numerous models of different reinforced concrete structures founded on soil containing voids using the finite element method to emphasize subsoil void effects on concrete buildings.
Static and dynamic analyses were performed to examine the response of structures resting on soils containing weak zones (voids) using ANSYS FE software. A wide range of parameters were studied for this analysis, such as void sizes and locations, heights and widths of the superstructure, types of foundation and subsoil, soil type, loading applied to superstructures, and the structural systems of the building. Numerous finite element models counting 550 models with the investigated parameters were analyzed. The static and dynamic responses of superstructures, such as foundation settlements, building lateral displacements, inter-story drifts, and the base shear force, were investigated for various cases of void shapes, sizes, and locations of different structures.
The influence of these parameters on the response of the structures was estimated. The critical zones under the various RC structures due to underground voids were estimated. In addition, equations for design were provided for the crucial area underneath concrete structures affected by underground voids, according to the building size, void location, and diameter. Finally, design recommendations for the assessment of structure behavior resting on soils containing voids/tunneled zones within the studied cases, were provided.