Analysis of Influence of Arc Cutterhead on Ground Settlement during EPB Shield Construction
(1 Key Laboratory of Transportation Tunnel Engineering of Ministry of Education, Southwest Jiaotong University, Chengdu 610031;2 Chengdu Construction Investment Co., Ltd., China Power Construction Corporation, Chengdu 610212)
Abstract：
During the shield tunnel construction, the form of cutterhead may have a certain impact on constructioninduced ground settlement. In view of this, the stress characteristics of balanced in-situ soil pressure in front of the arc and rectangular shield cutterheads are analyzed, the calculation formula of the balance pressure in the arc edge area and the selection method of the soil chamber pressure of the arc cutterhead are deduced, and the definition of the influence coefficient of the arc cutterhead is provided as well. FLAC3D numerical simulation software is used to analyze the ground settlement difference induced by excavation of arc and rectangular shield cutterheads, and the effects of soil pressure and soil unit weight in excavation chamber on ground surface settlement and tunnel face displacement. The results show that the ratio of ground settlement induced by arc and rectangular cutterheads obtained by numerical calculation is basically consistent with the influence coefficient of arc cutterhead obtained by theoretical analysis, which means that it is feasible to use this influence coefficient to evaluate the ground settlement differ? ence induced by rectangular and arc cutterheads.
WANG Yingxue1 LUO Yang1 ZHANG Ziwei1 WANG Guoyi2 SONG Xiangshuai1
.Analysis of Influence of Arc Cutterhead on Ground Settlement during EPB Shield Construction[J] MODERN TUNNELLING TECHNOLOGY, 2021,V58(6): 155-162
2021, Vol. 58 