| Too much resilience of foundation pits will occur during excavations since thefoundation ditches of high building are always deep and wide. During excavations,the stresses in the structure and foundation will be redistributed because of theexcessive resilience, and the surrounding buildings and subsurface pipes will beendangered. Therefore, it's too important for civil engineers to predict the heave ofditch's bottom. According to many measured-data of projects, foundation piles havecertainty effects to restrict the heave of ditch's bottom. Besides, the excavations havedeformed the piles. However, quantitative analysis considering foundation piles israrely carried out to calculate the resilience of foundation pit by three-dimensionalFEM, nor do the spatial effects of resilience.A 3-dimensional finite element model considering resilience's spatial effects isproposed in this paper. In this model, sequential excavations and strut installations aresimulated in the stratified soil, and soil nonlinearity is modeled using ModifiedCam-clay constitutive relationship. This method can be used to calculate the resilienceof foundation pit at any depth. This paper also analyzes spatial distributions ofresilience considering foundation piles in many cases. The study also brings forwardthe conception of "resilience field". Moreover, it is also analyzed some spatial factorswhich have influences on the resilience during excavations, such as ditch areas,shapes and depths. The resilience values of foundation pit in the ditch's corners aresmaller than those of the middle part, and the resilience values of the rectangularditches are smaller than those of the foursquare ones with the same excavation areasand depths. The paper deduces a feasible method of calculating the resilience offoundation pit under unloading.
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