Study On Security Early Warning System Of Deep Foundation Pit With Back Analysis Theory

The prevention and treating of deep foundation pit accident is a very important problem in geotechnical engineering, and it is a key problem in the deep foundation ditch engineering practice. A back analysis theory in engineering was used in this paper. The theoretic and practical study in the back analysis, security early warning system of deep foundation pit is set up using this theory.On the base of former study, the development and characters of deep foundation ditch engineering was expound perspicuity firstly. Aiming at the status and existing questions of the deep foundation pit engineering accident, the reasons of the deep foundation ditch engineering accidents was analyzed detailedly and generally reference to the articles of abroad and internal. The method of preventing and treating of deep foundation ditch accidents that set up security early warning system of deep foundation pit in back analysis was put forward in paper. The method of the back analysis parameter is introduced, and the normal analysis and optimum back analysis are very applicable in engineering. The back analysis method of the elastic foundation beam in linear elastic model is used to analyze the deformation of the retaining and protecting structure .And calculating the foundation excavation in plane finite element back method with program of Ansys. Then the calculation finding of two back analysis methods are compared with in-site engineering measurement data. And the application range of two methods is pointed out.At last, combining the practical engineering of the new Longpan road tunnel deep foundation pit in Nangjing, the flow of security early warning system of deep foundation pit in back analysis is bound and the key of security early warning system of deep foundation pit is expounded detailedly.