Analysis Of Contiguous Pile Wall As Deep Excavation Support System In Silty Soils Incase Of Adama Town.

Abstract

Development in urban areas around the world has rapidly increased in recent years. This rapid development has not been matched by the ever decreasing open space commonly associated with urban centers. Providing space for parking, public amenities, etc in multi-storey buildings at town centers has created a need to go deep excavations into ground. Deep excavation is often required for urban construction. Unfortunately, the ground movements associated with deep excavation can result in damage to adjacent buildings. Thus, it is critically important to accurately predict the damage potential of nearby deep excavations and designing adequate support systems. This thesis describes the analysis of contiguous pile walls as deep excavation support system in silty soils. A detailed analysis of deep excavation support system using PLAXIS 2D in silty soils at Adama town is furnished in this study with an objective to realistically simulates the deep excavation behavior. Some difficulties of not quite precise regulative have been encountered. Nevertheless, the proposed model has been able to describe the effects in the process of excavation in the selected material and loading conditions. This study presents details of problems with deep excavation, Analysis and design approaches of deep excavation support systems, Numerical and Analytical studies of deep excavations, laboratory and field performance measurements. Besides literatures on wall deformation, Ground movement, Earth and pore water pressure, Prop loads and wall bending moments, Deformation and damage of adjacent infrastructures are discussed to understand the design and construction trends of excavation support system. Numerical modeling and field studies are also discussed to predict the effect of model selection and precisely choose the best model that suits the selected soil type and area of study. Parametric study has been conducted to analyze the effects of surcharge and its location and pile diameter on horizontal displacement, vertical deformation and bending moment of the support system. Analysis results and discussion from the study are also presented with details of constitutive soil model used during analysis to analyze the suitability of contiguous walls as deep excavation support system during deep excavation and provide helpful first estimate of probable damages caused on adjacent structures due to excessive excavation. Limitations in the analyses and recommendations for future work are also presented at last.