Influence of Full-face Grouting of the Metro Tunnel on Ground Surface Heaving
(1 China Railway Southern Investment Group Co., Ltd., Shenzhen 518000; 2 China Railway Tunnel Consultants Co.,Ltd.,Guangzhou 511400; 3 School of Civil Engineering, Central South University, Changsha 410075)
Abstract：
Continuous heaving of ground surface occurs at certain mined section of Shenzhen metro due to high in? tensity grouting, with the maximum heaving exceeds 50 cm and no settlement occurrence during the subsequent tunnel excavation. Considering that it mainly consists of sandy cobbles and little coarse sand and fully weathered grani?telocated at the upper part and bottom,an analysis on the causes of ground surface heaving is conducted by theoretical analysis, numerical simulation and field measurement from the aspect of lifting by grouting.The results show that grouting has penetration compaction effect on the loose soil mass of this section and hydraulic fracture occurs under large grouting pressure; the directions of most grouting veins are horizontal;jet grouting pile constructed on the both side of grouting area changes the initial stress state of grouted stratum and increases the degree of ground surface heaving.
LIU Jiqiang1 XU Junwei2 DONG Zonglei3 ZHANG Xuemin3 YANG Junsheng3
.Influence of Full-face Grouting of the Metro Tunnel on Ground Surface Heaving[J] MODERN TUNNELLING TECHNOLOGY, 2020,V57(3): 147-153
2020, Vol. 57 