Evaluation of Behavior of a Deep Excavation by Three-dimensional Numerical Modeling

Abstract

To stabilize the urban deep excavations, soil anchoring is one of the methods that are very common for geotechnical engineers. Most of the previous studies have used a simplified the complex interaction and often they have overlooked the effects of three-dimensional (3D) modeling. In this study, the results of 11 3D finite element (FE) analysis of a deep excavation which supported with tie-back wall are presents. For this purpose, Firstly, the Texas A&M excavation which supported by two rows of ground anchors, soldier pile and wood lagging was modeled and secondly the results obtained from 3D numerical modeling have been compared with those obtained from measured data and the results of previous study. Then, the effect of ground anchors arrangement on the excavation behavior including horizontal displacement of the wall (δ_h) and surface settlement (δ_v) and their maximum values have been investigated. The results showed that a change in the value of SV₁ does not have a significant effect on the value of maximum horizontal displacement of the wall (δ_hm). The value of SV₁ has a significant effect on the value of (δ_v and by increasing its value from 1.5 m to 2.5 m; the heave created at edge of the wall disappears and at d≥–1 m surface settlement created. When D_e=16 m, a variation in ground anchors arrangement significantly affected the values of maximum surface settlement ((δ_vm) as compared to δ_hm. The results presented in this study can be helpful for designers without experience and information of previous designs.