The Calculation Method Consider The Displacement Effects For Uppotring Structure In Deep Excavation

With the rapid development of urban construction, the development of underground space is imperative. In deep foundation works, the dense surrounding buildings, cluttered pipeline distribution, the small site, etc. Bring a great deal of difficulty and complexity of deep excavation works. Original part of the classical theory and supporting method has not been able to meet the actual needs, the classic Rankine earth pressure theory and the Coulomb earth pressure theory are derived of the hypothesis that the soil in the state of limit equilibrium. However, the actual supporting structure is difficult to achieve so large displacement of the limit state. The earth pressure of soil in a non-limit state and its distribution situation is not only related with the soil,but also largely depending on the deformation situation of the supporting structure.In deep excavation works, for the row of piles prestressed bolt supporting structure, the earth pressure on the supporting structure on the pile is changed by pile deformation, between the soil and the supporting structure is a nonlinear interaction relationship. Based on this point, according to the elastic foundation beam model that proposed by Winkler, Using a series siol spring to represent the role of soil on the pile, establish the earth pressure calculation model which consider the impact of displacement, make the calculated value is more close to earth pressure in the role of supporting structure of the earth pressure on practical value.For the non-linear relationship between the soil and supporting structure, Many scholars at home and abroad propose increment method to solve this problem through a lot of researching, increment method can effectively track the process of deformation of the supporting structure, reflects the influence of the loading path. However, it use a series of linear problems to approximate nonlinear problems, with the increasing of loading, the calculation error will be increasing and could eventually lead to results do not converge. Iterative method for solving nonlinear problems can make the calculation results better converge, but it can not be considered to supporting structure of the deformation process. Mixing calculation, that Let incremental and iterative comprehensive applied to the calculation of the supporting structure can control calculation error in the small range, and can be a good description of the liner relationship between loading and displacement.Using MATLAB software to make mixing calculation be a program, and applied to practical engineering, compared with the calculated results of traditional deep excavation design software (LIZHENG), will get a calculated results more closed to the actual internal forces of supporting structure. Thus, proving the method proposed in this article has good applicability, and can be widely used in practical engineering after improving.