الفهرس 
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Abstract
This thesis aims to study the performance of micropiled raft foundations under combined vertical and lateral loading using finite element modeling. Although the behavior of micropiled raft foundations has been reported, no guidance is available to show their lateral performance under combined loading. Therefore, the primary goals of the current study are to assess the behavior of laterally loaded micropiled rafts and examine the effects of different parameters on their performance. Several factors were investigated throughout the thesis: micropiles spacing, raft thickness, the magnitude of vertical loading, and micropiles’ length and arrangement. The difference between the lateral performance of a primary micropiled raft and that of an existing raft enhanced by underpinning micropiles was also investigated. Not only was the behavior of micropiled rafts investigated under combined loading, but numerous guidelines were also introduced to help design practitioners improve the lateral capacity of micropiled rafts by installing inclined micropiles or using permanent steel casing. The lateral load capacity of the micropiled raft, the bending moment, and the shear force along the micropiles depth were estimated for various configurations. Moreover, the load-sharing ratio between the micropiles and the raft was assessed. The study mainly reveals that increasing vertical loads causes a continuous decrease in the lateral load capacity of micropiled rafts over soft clay. Inclined micropiles offer a greater lateral load-sharing ratio (αh) than that of vertical ones, largest at θ=45°.