摘要
研究目的:针对应用随机介质理论预测盾构施工过程中诱发的地表沉降量时盾尾隧道断面收敛量的确定问题,文中在考虑盾构施工工艺的基础上,结合工程地质条件,并运用弹性力学的相关理论知识计算出随机介质理论预测地表沉降所需的参数。本文意在利用随机介质理论预测地表沉降量时,将预测计算所需参数可以进行量化计算,并能对影响其大小的各个因素针对施工环境进行优化。研究结论:通过对西安地铁隧道盾构施工诱发的地表沉降分析表明:(1)在盾尾断面收敛量的影响因素中,偏心超挖的影响最为敏感,而且最不容易控制;(2)盾尾应力释放引起的收敛变形是控制地表沉降的关键因素,而在弹性变形范围内,适当的增大注浆压力可以控制盾尾应力释放引起的隧道断面收敛量,有效地减小地表沉降;(3)使用本文提出的计算断面收敛量的方法并结合随机介质理论预测得到的地表沉降数据和沉降曲线趋势与实际结果符合;可对土体结构致密、强度较高的黄土地层中盾构施工中地表沉降控制措施的采取提供一定的理论依据。
Research purposes： For the problem of calculated the cross - section convergence when use the stochastic medium theory to predict the surface subsidence induced by shield construction, on the basis of consideration of shield construction technology, combined with the engineering geological conditions, this paper uses the theory of elastic mechanics knowledge to calculate the parameters needed for the stochastic medium theory to predict the surface subsidence. The purpose is that can quantify the parameters of section convergence and optimize the factors which affect convergence value when use the stochastic medium theory to predict the surface subsidence. Research conclusions：Through the analysis of surface settlement of Xihn subway tunnel induced by shield construction, the results show that ： （ 1 ） Among these three factors which affect ground settlement, the influence of eccentric overbreak is the most and is the most difficult to control. （2） The key factor to control the ground settlement is controlling convergence deformation which caused by stress release in shield machine tail, and in the range of elastic deformation, increasing grouting pressure properly can control section convergence value and reduce ground settlement. （3） The predicted results of surface subsidence which are got from the method for calculating convergence value of section in this paper and stochastic medium theory are matched well with the actual results. And it will provifded a certain theoretical basis to develop the control measures for reduced ground surface subsidence by shield construction in the compact structure of soil mass and high strength of loess strata.
出处
《铁道工程学报》
EI
北大核心
2014年第3期110-116,共7页
Journal of Railway Engineering Society
关键词
随机介质理论
地表沉降
断面收敛
施工因素
弹性理论
stochastic medium theory
surface settlement
section convergence
construction factors
elastic theory
