TUNNEL PILE INTERACTION & SETTELMENT ANALYIS OF PILES UNDER INFLUENCE OF TUNNEL USING PLAXIS 2D

Abstract

On each passing day competition for surface area/space is increasing in such situation to satisfy the target of sustainable development & utilization of subsurface/underground space turns out to be vital. Underground designs although being difficult, troublesome and uneconomical to develop, restricted only to just some special structures like tunnels, hydropower stations, mining, etc we are forced to use then urban areas due to lack surface space. Being said that we should also attract our attention that in a rising number of cases where a portion of public structures are likewise being built underground which is close to vicinity or near to the metro tunnels in urban areas for that reasons though it is effective and successful utilization of land and area ,this type of situation where existing structure is in the radius of influence of each other it poses a great threat for both the tunnel and surface structure. Hence, we can say that in urban/metropolitan areas or at any urban environment, it is very common to find tunnel having influence over an existing pile foundation and inevitably affecting or compromising the settlement of soil. Hence, this paper discusses the influence of newly built tunnel on the existing pile foundation using FEM (Finite Element Method), so the aim of this paper is to provide parametrical study to assess the extent of the settlement problem near piles. The numerical model which we have used to access the situation was modelled using PLAXIS 2D software. In which the plane strain model with 15 noded elements was defined therefore 2D plane strain approach was used to analyze the loading of pile rows & influence of tunnelling on the pile rows. There is a variation of position of tunnel corresponding to which the variation of the total displacement of pile is observed. Then these results are analyzed & as per which settlement criteria along with design guidelines are defined.