| With the rapid growth of China’s economy,increasing of high-rise building and large multistory basement,super large deep foundation pits have also increased.For example,there are other important buildings adjacent to the foundation pit and underground traffic tunnel is also very common near to the foundation pit.It is difficult to result in foundation pit by hand outward part of the anchor,and the super large foundation pit are also created using traditional the inner support method becomes more and more difficult,there cannot be an anchor,also difficult to hold the dilemma.The new slope-side reversed construction method is to use the reverse construction method of several major structures of the basement of the pit(a certain amount of lateral-resisting shear wall which perpendicular to the pit side diaphragm wall and also as a permanent structure).Such a number of sub-basement major structures serve as the effective lateral support of the retain structure is a new type of deep foundation retaining method.Compared with the traditional reverse method,the new slope-side reversed construction method requires only a few spans of construction at the edge of the pit.The reduction of the reversed area brings convenience in construction,the central area away from the edge can be excavated according to normal construction,and shorten the unearthing cycle and reduce construction costs effectively.In this thesis,the lateral-resisting stiffness of the slope-side reverse structure with excavation depth of 15 to 25 m is studied by the new method of slope-side reverse construction,and discussed in a new case of the new slope-side reverse method,the effect of the lateralresisting stiffness by reversed width,section height of lateral-resisting shear wall,arrangement of lateral-resisting shear wall,floor system,bedrock depth,temporary rigid partition between lateral-resisting shear wall and other factors is shown in the case study.The results show that the cross-section height of the lateral-resisting shear wall and the lateral-resisting stiffness of the temporary rigid baffle are more significant,and the influence of the bedrock depth on the lateralresisting stiffness is greater.The lateral-resisting shear wall layout and the lateral-resisting stiffness of the floor system have a certain influence,while the effect of the reverse width on the lateral-resisting stiffness is not obvious.In this thesis,the new slope-side reversed construction method is proposed.The MATLAB software is used to simulate the floor and retain structure and the bilinear quadrilateral element to simulate the lateral-resisting shear wall,and the unit is subdivided to obtain higher the plane numerical simulation analysis method of calculation accuracy is also proposed.The calculation method of calculating the nodal earth pressure and nodal soil spring stiffness by definite integral calculation of the earth pressure function and the integral calculation of the soil spring stiffness function is proposed.This paper also uses the MIDAS GTS NX software to perform planar finite element modeling analysis and 3D finite element modeling analysis for the case of new slope-side reversed construction method.The soil layer and the rock layer are simulated by modified Mohr-Coulomb constitutive model,steel components and the concrete members are simulated by elastic constitutive model,and the results of plane finite element analysis,three-dimensional finite element analysis,MATLAB software plane numerical simulation results and the deformation monitoring results of the construction site are compared with each other to verify the MATLAB software proposed in this paper.The correctness of the plane numerical simulation calculation method is verified.The numerical simulation analysis of the new slope-side reversed construction method in this paper has great significance for understanding the deformation theory analysis of the slopeside reverse method.It has reference value for the similar large-scale deep foundation by slopeside reverse method. |
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