Force Analysis And Deformation Characteristic Analysis Of Retaining Structure Under Asymmetric Excavation Condition

With the rapid development of underground construction and increasingly harsh conditions of deep excavation, two or more different asymmetric excavation foundation pits are becoming more common. It has become more important for how to consider asymmetric excavation in excavation engineering. Now, theoretical research lags behind engineering practices and no standards can be referenced. Ignoring the influences caused by two different asymmetric excavation, traditional method to solve this problem is simplifying the asymmetric excavation as symmetrical and using the deeper side in calculating. So, it makes sense and has the value of practical application. Based on that, those work have been done.1. Firstly, analytical solutions of calculating force on retaining structures of foundation pit which can consider the influences caused by two different asymmetric excavation have been deduced based on the equivalent beam method. The insertion ratio caused by two different asymmetric excavation have been investigated. The results shows that, insertion ratio of retaining structures located on the side of shallower depth of pit increases compared with calculating results without considering two different asymmetric excavation. The results can improve the asymmetric excavation pit design method, and provide a useful and economic reference.2. Based on principle of minimum potential energy, deformation of piles in symmetric excavation have been investigated (with or without struts). Parameter analysis also have been done like length of the excavation, the position of struts, the spacing of piles. The application of deformation analysis by principle of minimum potential energy has been expand to two asymmetric excavation.3. A 3D finite element model about two asymmetric excavation has been established. The deformation of top beam and retaining structure are obtained by the 3D model. Compared the results from finite element model and theoretical calculation presented in this paper, the validity of the theoretical calculation have been proved.