Numerical analysis on foundation underpinning method for constructing underground space

As the weight of the existing building is supported by the braces under the top beams and slabs of basement, columns and base slabs constructed, spread foundation underpinning method can be used to add basement of existing buildings in soft soil. Numerical models of three-dimensional finite element analysis based on Ansys code are established to study the settlement of socles on foundation underpinning construction. Some conclusions are drawn as follows: In the course of the foundation underpinning and basement constructed along some axis, the differential settlements of adjoining socles of underpinned parts in vertical direction of soil dug increase remarkable; on the contrary , the differential settlements of adjoining socles in parallel direction of soil dug have little change except underpinned parts. After the foundation and basement of several axis have constructed, the differential settlement of adjoining socles in boundary of underpinned parts and parts have not been underpinned is the maximum in vertical direction of soil dug. Compared the maximum of differential settlements with allowable value of code, the results provide basis for strengthening.