Abstract：
Back-analysis was conducted to determine internal tunnel forces causing support failures of a large-span railway station tunnel excavated by double-side heading method on the basis of measured horizontal convergence movements. Results demonstrated that excessive local deformations of the diaphragm walls at the lower bench level occurred and the subsequent heading excavation greatly affected the temporary support structure. The temporary support structure at the lower bench sustained large bending stresses, which resulted in cracking failure. Both the axial and bending strains of the previous temporary support were larger than that of the later ones due to repeated effects of subsequent construction, and the failures were more serious.
2011, Vol. 48 