The Deformation Monitoring Of Retaining Structure And Numerical Simulation About Deep Foundation Pit In Shenyang

Deep foundation pit engineering is one of the hot and difficult problems in rock soil engineering. How to effectively control deformation of foundation pit and make foundation pit engineering safe and economical is the task that people always probe. Deformation for retaining structure of foundation pit is an important factor for effect on the deformation of foundation pit. On the basis of reading lots of relevant researches at home and abroad and summarizing former research achievement, in view of displacement, deformation of deep foundation pit during the processing of deep foundation excavations, analyses of calculation method for excavation by steps and practical engineering measurement have been finished, on the ground of engineering of support of deep foundation pit in Shenyang. Then using PLAXIS finite element software, the deformation of retaining piles, surface subsidence and basement uplift of deep foundation excavation have been calculated in the progress of excavation of the practical engineering. The effect of the position of the first floor anchor on the deformation of the foundation pit was studied. The main contents and results are as follows:The horizontal displacement of pile increases with the deep of the foundation pit. The maximum horizontal displacement appears on a half length of retaining pile. The curve of the horizontal displacement of pile is big in the middle and small at both ends;The maximum of horizontal displacement of soil occurs in a certain depth below the excavation face. The horizontal displacement of soil being apart from the foundation pit slope 2.5times the size of foundation depth will be produced. The maximum of ground surface settlement occurs at a distance of 1.1 times the depth of the excavation from foundation pit slope. The range of ground surface settlement caused by excavating is 2 times the size of foundation pit depth;The quantity of the uplift of soil around the excavation face is large. With the depth increasing, the quantity of the uplift of soil is smaller. The range of uplift of soil caused by excavating is 1 times the depth of foundation pit depth;The position where the first anchor cable was installed on the pile has a significant effect on the displacement of the pile. Raised the first anchor cable position can significantly reduce the horizontal displacement of the pile top, but the displacement of the pile bottom is bigger than before. The result will be reversed if the position of the first anchor cable position goes down.