注浆压力非均匀分布引发的地表沉降计算及其影响因素分析  

Calculation and influence factors analysis of surface subsidence caused by non-uniform distribution of grouting pressure

作　　者：邓皇适 傅鹤林[1] 史越[1] 赵运亚 张运良[1] DENG Huangshi;FU Helin;SHI Yue;ZHAO Yunya;ZHANG Yunliang(School of Civil Engineering,Central South University,Changsha 410075,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075

出　　处：《中南大学学报（自然科学版）》2021年第10期3550-3558,共9页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51978668,51538009,51578550)。

摘　　要：盾尾同步注浆能有效控制盾构施工引发的地表沉降,被广泛应用于城市盾构隧道工程建设,现有研究常将注浆压力简化为均布压力,忽略了注浆浆液性质及其扩散作用,导致沉降预测结果不合理,为此,本文首先考虑同步注浆浆液非均匀扩散作用,基于Mindlin解,推导得到注浆压力空间非均匀分布引发的地表沉降计算公式;其次,对比现场监测数据验证公式的适用性;最后,讨论浆液塑性黏滞系数、掘进速度以及盾壳长度对地表变形规律的影响。研究结果表明:由地表沉降计算公式所得地有沉降与现场监测结果吻合度高,验证了该计算公式的正确性;将注浆压力简化为均布压力大大削弱了注浆压力的沉降控制效果,地表隆起量仅为考虑注浆压力非均匀分布时的20%;注浆压力引起的地表隆起量及影响范围随浆液塑性黏滞系数及盾壳长度减小而增加,掘进速度变化对地表隆起的影响较小。Shield tail synchronous grouting can effectively control ground settlement caused by shield construction, and it is widely used in urban shield tunnel construction. In the existing research, grouting pressure is often simplified to uniform pressure, and the properties of the grouting liquid and its diffusion effect are ignored,which makes the settlement prediction result unreasonable. Firstly, considering the non-uniform diffusion of the synchronous grouting slurry, based on the Mindlin solution, the calculation formula of surface settlement caused by the non-uniform distribution of the grouting pressure space was derived, and it was applied in engineering calculation. Secondly, the calculated results were compared with the field monitoring results for validation.Finally, the influence of different slurry plasticcity coefficients of viscosity, excation speed and shield shell length on the surface deformation law was studied. The results show that the results obtained by the derived formula are in good agreement with the field monitoring results, which verifies the correctness of the formula. Treating the grouting pressure as a uniform pressure greatly weakens the settlement control effect of the grouting pressure, and the amount of surface uplift is only 20% of the non-uniform distribution of grouting pressure. The size and influence range of the surface uplift caused by the grouting pressure increase with the decrease of plastic viscosity coefficient of grouting and the length of the shield shell. The change of the excavation speed has little effect on the surface uplift.

关 键 词：注浆压力 非均匀分布 MINDLIN解 地表沉降 因素分析 

分 类 号：U453.6[建筑科学—桥梁与隧道工程]