Research on Nonuniform Support of System Anchor Bolts
(1 Key Laboratory of Transportation Tunnel Engineering, Ministry of Education, School of Civil Engineering, Southwest Jiaotong University, Chengdu 610031; 2 China Railway Eryuan Engineering Group Co. Ltd., Chengdu 610031)
Abstract：
Using the four-track Wumengshan No.2 railway station tunnel as an example, a numerical simulation was performed to study nonuniform support of the system anchor bolts adopted in a multi-partition excavation. The results indicate that: under uniform support of the system anchor bolts, the order of axial force magnitude is "spandrel (partition ① and ②) > arch springing (partition ④ and ⑤) > sidewall (partition ⑥ and ⑦) > crown (partition ③)," with obvious nonuniformity at different excavation partitions; the axial force on the left and right sides of the anchor bolts at the arch springing and sidewall are asymmetrical, i.e., it is larger at the former excavated side than it is at the latter one; the axial force of the anchor bolts is minimal at the crown and has almost no effect. An analysis of nonuniform support of the system anchor bolts is carried out based on different lengths, diameters, and intervals of anchor bolts, and comparison is undertaken with the uniform support. Based on the results, consumption of the anchor bolts is 37%, 36%, and 36.93% of the original consumption at the spandrel, arch spring, and sidewall and crown, respectively, thereby achieving significant economic benefits.
ZHANG Hui-Jian-1,
CHOU Wen-Ge-1,
ZHAO Bin-1 etc
.Research on Nonuniform Support of System Anchor Bolts[J] MODERN TUNNELLING TECHNOLOGY, 2015,V52(1): 98-104
2015, Vol. 52 