Evaluation of Building Weight and Geometry Influence on the Surface Settlement due to Sequential Excavation Method Using Numerical Finite Element Approach

Considering upward trend of traffic congestion in mega cities، construction of urban tunnels (road or metro) is inevitable. The reciprocal effect of tunneling-induced ground settlement and surface buildings is an important factor during shallow tunneling design procedures in urban areas. Hence، the effective factors in this reciprocal relationship need to be appraised prior to the construction phase. In this paper، the major characteristics of buildings were numerically simulated using 3D finite element approach. It has been demonstrated that weight and length of buildings have showed parallel correlation with surface settlements. However، building width have had reverse trend with surface settlements. The main purpose of this research is the study of influence of building weight and geometry on the surface settlement due to sequential excavation method، and interaction between buildings and tunnel. It investigated by simulating of systematic construction process of tunnel using numerical method. Methodology and Approaches: In this paper، the major characteristics of buildings were numerically simulated using 3D finite element method. In addition، results of a study on field data of the Nyayesh tunnel are presented. Results and The results have proved that the existence of surface buildings has reciprocal effects on ground settlement troughs. The increase of the building weight will result in increase of surface settlements. On the contrary، by ignoring building weight، presence of surface building foundations will cause a less settlement compared to the green field condition which is due to increase of the rigidity of building foundation and thereby ground improvement. The increase of building width reduces the surface settlements، and the increase of the building length leads to more surface settlement، although the building width is a more effective parameter، which controls the overall tunneling-building interaction behavior than building length. Thus، building weight and geometry effectively influences the surface settlements troughs in urban tunneling.