Combination reinforcement mechanism of sub-horizontal jet-grouting and pipe roof in water-rich soft stratum
SHI Yu-feng1, CAI Li-ping2, YANG Jun-sheng3, HU Wen-tao1
1. School of Civil Engineering and Architecture, East China Jiaotong University, Nanchang 330013, China; 2. Guangzhou Railway(Group) Corporation, Guangzhou 510010, China; 3. Central South University, Civil Engineering School, Changsha 410075 China
Abstract：The horizontal jet-grouting pile, which is applicable in soil reinforcement and water isolation, is hard to assemble an ideal homogeneous sealed pre-reinforced shell accounting for the restriction of geological condition, material characters and construction technology. For improvement, a composite pre-reinforcement technique utilizing horizontal jet-grouting piles and large pipe shed is proposed. The corresponding 3-D numerical model considering fluid-solid coupling effects is established using FLAC3D for further analysis. The results show that the range of the plastic zone decreases by adding extra pipe shed beneath the piles. The “arch support effect” of piles in horizontal direction and “beam support effect” of shed in vertical direction can be fulfilled. With this technique, the value of the stretch stress of the horizontal rotary jet-grouting piles will be reduced, which results in better stability and reinforcement effect of piles. This technique is successful applied in the water-rich section of Jiangmen tunnel in Guangzhou-Zhuhai Railway, which may provide suggestions for similar projects.
石钰锋, 蔡理平, 阳军生, 胡文韬. 富水软弱地层隧道水平旋喷与大管棚预支护研究及应用[J]. 岩土工程学报, 2015, 37(zk2): 101-106.
SHI Yu-feng, CAI Li-ping, YANG Jun-sheng, HU Wen-tao. Combination reinforcement mechanism of sub-horizontal jet-grouting and pipe roof in water-rich soft stratum. Chinese J. Geot. Eng., 2015, 37(zk2): 101-106.
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