Study On The Calculation Method Of Pile Anchor Reinforcement Of Foundation Pit

Nowadays, the traditional design method and calculation model of pile anchor retaining structure has developed quite thoroughly. At the same time, it is so convenient to check the safety and accuracy of the result by mature software. However, in recent engineering practice, there are some problem existing in some special foundation pit analysis. Firstly, the deepening of the foundation pit. For the shallow depth foundation which is in constructing or under constructed, in the full use of former supporting part, the reinforcement piles and anchor will be set in the foundation pit to reinforce and deepen the former supporting system. Secondly, the reinforcement of existing supporting system.However, in the design of practical engineering, the theory and research of the reinforcement pile anchor supporting design is still in the blank stage. When in this certain stance, the design personnel often choose a simplified design to finish the practices by turning their own experiences and using design software. The simplified design may increase the engineering cost or lead some unsafe results. Therefore, for this certain reinforcement foundation pit, it is of great importance in theory and remarkable valuation in engineering practice to explore a new calculation theory and model of accurate and closing the actual situation of the project.This paper gets following main innovating achievements:1 In the case of ignoring the interaction of the original pile and reinforcement pile, this paper has established the displacement and stress equations of the original pile and reinforcement pile, considering the excavation process and anchor settings. Though solving the equations, it results the the displacement and stress of the original pile and reinforcement pile and the stress of each anchor under different working conditions. This method called divided calculation.2 In the case of considering the interaction of the original pile and reinforcement pile, this paper has established the displacement and stress equations of the whole pile, considering the excavation process and anchor settings. Though solving the equations, it results the displacement and stress of the whole pile and the stress of each anchor under different working conditions. Based on the calculation result of the whole pile, the stress of original pile and reinforcement pile could have been weighted average by pile bending stiffness. This method called combined calculation.3 Though the comparison the results of combination and dividing calculation of the original pile and reinforcement pile, it shows the results of combination calculation are more closer to the actual situation as it could consider the displacement and stress of each pile and the stress of anchor in different working condition as a whole.4 In this paper, it has been completed the corresponding calculation by program FORTRAN of the pile anchor reinforcement of foundation.