Shield tunneling and post-tunneling steady seepage are accompanied by stress and displacement variations,which could induce and influence the soil arching effect.Although there are many studies on the tunneling-induce...Shield tunneling and post-tunneling steady seepage are accompanied by stress and displacement variations,which could induce and influence the soil arching effect.Although there are many studies on the tunneling-induced soil arching effect,the research about the effect of seepage on soil arching effect is extremely lacking.In this study,a numerical model is firstly established and verified by field data.Then,a series of numerical models,whose simulation method of steady seepage is verified by adopting the conformal mapping technique,are established to study the soil arching evolution of deep-buried tunneling and post-construction steady seepage.The results indicate that seepage leads to an increase in effective vertical stress,which is consistent with the existing theory.The seepage weakens the soil arching effect resulting in the height of the arch zone reducing from 2.38D(D is the tunnel diameter)to 1.25D.The seepage leads to the further development of ground consolidation settlement,but the differential displacement in the soil mass decreases.The ground reaction curve in the steady seepage condition shows a bigger value than that after excavation.It is reasonable to control the ground loss ratio in the range of 0.5–1.0%,which can minimize overburden pressure with moderate ground deformation.展开更多
1Introduction Several characteristics of natural soils complicate the relationship between their mechanical behaviour and geotechnical construction and maintenance in the field.These characteristics include the presen...1Introduction Several characteristics of natural soils complicate the relationship between their mechanical behaviour and geotechnical construction and maintenance in the field.These characteristics include the presence of three phases(solid particle,water,and air),particle constitutions of various minerals(such as quartz,kaolinite,and montmorillonite),and an exceptionally wide range of particle size fromμm-scale(clay particles smallerthan2μm)to100-mm scale(suchas somegravelsandpebbles)。展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.52090082,51938005,52122807,and 52108318)China Hunan Provincial Science&Technology Department(Grant Nos.2021RC3043 and 2021JJ30119).
文摘Shield tunneling and post-tunneling steady seepage are accompanied by stress and displacement variations,which could induce and influence the soil arching effect.Although there are many studies on the tunneling-induced soil arching effect,the research about the effect of seepage on soil arching effect is extremely lacking.In this study,a numerical model is firstly established and verified by field data.Then,a series of numerical models,whose simulation method of steady seepage is verified by adopting the conformal mapping technique,are established to study the soil arching evolution of deep-buried tunneling and post-construction steady seepage.The results indicate that seepage leads to an increase in effective vertical stress,which is consistent with the existing theory.The seepage weakens the soil arching effect resulting in the height of the arch zone reducing from 2.38D(D is the tunnel diameter)to 1.25D.The seepage leads to the further development of ground consolidation settlement,but the differential displacement in the soil mass decreases.The ground reaction curve in the steady seepage condition shows a bigger value than that after excavation.It is reasonable to control the ground loss ratio in the range of 0.5–1.0%,which can minimize overburden pressure with moderate ground deformation.
基金the Research Grants Council(RGC)of Hong Kong Special Administrative Region Government(HKSARG)of China(Nos.15217220,15220221,15226822,and N_Poly U534/20)。
文摘1Introduction Several characteristics of natural soils complicate the relationship between their mechanical behaviour and geotechnical construction and maintenance in the field.These characteristics include the presence of three phases(solid particle,water,and air),particle constitutions of various minerals(such as quartz,kaolinite,and montmorillonite),and an exceptionally wide range of particle size fromμm-scale(clay particles smallerthan2μm)to100-mm scale(suchas somegravelsandpebbles)。