Rapid Construction Technology for a Shallow-buried Bored Tunnel in Sandy Pebble Stratum
(1 Beijing Rail Transit Construction Management Co., Ltd, Beijing 100037;
2 Beijing Municipal Construction Group Co., Ltd., Beijing 100045;
3 Civil and Architectural Engineering Institute of Beijing Jiaotong University, Beijing 100044)
Abstract:
The running tunnel of phase three of the Beijing Subway Line 4 passes through a sandy pebble stratum, which creates construction risks of surrounding rock collapse, tunnel bottom swell, sand outflow and soil settlement above the roof. It also affects the road and bridge safety and results in difficult drilling and grouting. This paper addresses the optimization of the design and grouting parameters of small conduits and discusses the construction principles of "early covering, fine short tube, less disturbance, quick setting, abutment reinforcing and middle slotting" regarding the bored tunnel with a shallow overburden at the sandy pebble stratum. The construction technology of the bench method is introduced, which includes the key points of counter core soil excavation, small conduit grouting and locking anchor pipe, with a monthly advance rate of 60~70 m.
LIU Kui-Gang-1,
Wang-Wen-Zheng-2,
Pei-Shu-Feng-3
.Rapid Construction Technology for a Shallow-buried Bored Tunnel in Sandy Pebble Stratum[J] MODERN TUNNELLING TECHNOLOGY, 2011,V48(5): 115-120