Mechanics of deep excavation’s spatial effect and soil pressure calculation method considering its influence
LI Da-peng1,2,TANG De-gao1,YAN Feng-guo1,HUANG Mu1
1. State Key Laboratory for Disaster Prevention and Mitigation of Explosion and Impact,College of Defense Engineering, PLA University of Science and Technology, Nanjing 210007, China; 2. No.5 Air Defense Engineering Department of PLA Air Force, Nanjing 211100, China
Taking the soil body around the deep excavation as subject investigated, according to the position-relationship between soil arching and slip plane, the forming mechanics of deep excavations spatial effect was analyzed. According to the stress states of micro soil elements affected and not affected by the spatial effect, an earth pressure equation considering spatial effect was derived. Studies show that the essence of spatial effect is the influence of soil arching around excavation to the characteristics of earth pressure and support deformation, and it’s more appropriate to take the ratio of length to depth when researching spatial effect. The earth pressure equation considering spatial effect can calculate the earth pressure at different position on the support precisely. The equation has two variables related to position’s depth and distance to excavation corner, covering the shortage of earth pressure equation only related to depth in code of excavation design. An example analysis shows that the equation can to reflect the earth pressures distribution condition of the retaining structure．
LI Da-peng,TANG De-gao,YAN Feng-guo,HUANG Mu. Mechanics of deep excavation’s spatial effect and soil pressure calculation method considering its influence. JOURNAL OF ZHEJIANG UNIVERSITY (ENGINEERING SCIENCE), 2014, 48(9): 1632-1639.
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