Abstract In order to study the relationship of the face support pressure and the ground surface deformation of a shield-driven tunnel, a self-made model testing system is used to measure the ground surface deformation and the face support pressure of a sand sample, and the relationship between the two is then analyzed. A failure model for soil settlement and heaving ahead of the excavation face is established by measuring the disturbance area at different overlying depths. Based on the gained relation curves of the face support pressure and the ground surface deformation, a deformation of 0.2% of the excavation diameteris taken as a reference value for setting the face support pressure, and the upper and lower limits of the ultimate support pressure for maintaining face stability are given by considering the Rankine earth pressure formula. For convenience of application, the required support pressure values for keeping specific ground surface deformation are suggested.
Abstract：
In order to study the relationship of the face support pressure and the ground surface deformation of a shield-driven tunnel, a self-made model testing system is used to measure the ground surface deformation and the face support pressure of a sand sample, and the relationship between the two is then analyzed. A failure model for soil settlement and heaving ahead of the excavation face is established by measuring the disturbance area at different overlying depths. Based on the gained relation curves of the face support pressure and the ground surface deformation, a deformation of 0.2% of the excavation diameteris taken as a reference value for setting the face support pressure, and the upper and lower limits of the ultimate support pressure for maintaining face stability are given by considering the Rankine earth pressure formula. For convenience of application, the required support pressure values for keeping specific ground surface deformation are suggested.
.Model Test of the Relationship between the Face Support Pressure and Ground Surface Deformation of a Shield-Driven Tunnel in Sand Stratum[J] MODERN TUNNELLING TECHNOLOGY, 2015,V52(2): 44-51
2015, Vol. 52 