الفهرس 
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Abstract
Continuous Flight Auger (CFA) pile installation technique is widely used technique in deep piles installation. Despite the several advantages of this technique especially economy, quick installation and reduced vibration compared to other pile installation techniques. In this study, comprehensive review on the possible causes of unfavorable pile drilling conditions including soil related reasons and auger rotation. Also, several reliable case studies reported in the literature where the CFA pile installation has resulted in sever distresses in adjacent structures. In order to investigate the possible effect of the pile installation on the adjacent structures, 3D numerical analyses have been used. In this study, a simplified procedure to model single CFA pile installation was proposed. The proposed simplified procedure assumptions have been made based on observations in the literature review. The proposed procedure was conducted to simulate both favorable and unfavorable CFA pile drilling and for single and group of piles. Single CFA pile drilling is simulated to calculate possible settlement and subsidence that may resulted from pile installation. Several factors have been studied. The results showed that there are possible surface deformations calculated due to CFA pile drilling even in case of favorable conditions. This possible settlement has the shape of inverted conical shape at the center of the pile. The pile group CFA installation was investigated using the same proposed procedure. Several scenarios were assumed for the sequence of pile installation to determine the sequence that may have minimal possible settlement adjacent to the pile drilling site. The recommended scenario with minimal settlement in which the piles will be installed by leaving two piles and drill the next one and then drill the left piles (the distance left between the drilled piles in each stage of construction is about 0.6 to 0.7 of the pile length). Finally, a chart was developed to assess the possible extent of calculated settlement on the surface and possible effect on the adjacent structures. This chart is based on observations and case studies in the literature and 3D numerical analyses conducted for 3D numerical model. This chart may help practitioner to evaluate approximately the possible effects of CFA pile drilling on adjacent structures.