复变函数法分析盾构隧道开挖引起的土体位移和衬砌变形

发布时间：2018-02-10 15:54

本文关键词： 盾构隧道复变函数椭圆化变形土体位移衬砌变形　出处：《岩土工程学报》2017年09期 　论文类型：期刊论文

【摘要】：盾构隧道开挖引起的地层变形历来是人们所关注的重要课题。目前,既有成果较少考虑隧道衬砌与土体相互作用所带来的影响,尤其是较少针对衬砌变形进行分析,就此基于隧道椭圆化变形边界条件,提出了考虑衬砌与土体两种不同介质相互作用下的地层位移和衬砌变形复变函数解答。在该方法中,隧道埋深只影响共形映射后圆环域的环壁厚度,而解析区域依然保持圆形,具有不会对函数解析产生影响的优势;此外,该法经共形映射后保证了边界连续性,避免了既有应力函数法为保证隧道扰动土体无穷远处位移为零,而对解析解进行修正所导致物理意义不明确的缺陷。通过实例分析,得到了隧道开挖引起的地表沉降,并与实测数据进行了对比验证;通过参数分析,获取了扰动地层和隧道衬砌变形的影响规律。结果表明:复变函数解答得到的土体位移曲线与实测值吻合较好,且地表最大沉降值更接近于实测值;隧道的埋深和半径对土体位移和衬砌变形均有较大影响,衬砌厚度对其影响虽然较小,但仍不可忽略;衬砌径向位移曲线呈仰卧的鸭蛋形,关于90°/270°轴对称,拱顶和拱底被压扁,拱顶压缩量明显大于拱底,左、右两侧压缩量小于上、下两侧,表现为收缩之后又被压扁向左、右两侧突出,且随着埋深的增大,衬砌整体上浮;衬砌环向位移曲线呈侧立的苹果形,关于0°/180°轴对称,且在90°和270°处取值为零,随着隧道埋深的增大,环向位移绝对值增大。
[Abstract]:The ground deformation caused by shield tunnel excavation has always been an important subject of concern. At present, the existing achievements seldom consider the influence brought by the interaction between tunnel lining and soil, especially the analysis of lining deformation. Based on the elliptical deformation boundary condition of tunnel, the complex function solution of stratum displacement and lining deformation considering the interaction between lining and soil is presented. The depth of tunnel only affects the thickness of the ring wall after conformal mapping, but the analytic region is still circular, which has the advantage of not having an effect on the function analysis, in addition, the conformal mapping ensures the continuity of the boundary. The existing stress function method is used to avoid the defect that the existing stress function method can ensure the infinite displacement of the disturbed soil is zero and the physical meaning is not clear due to the modification of the analytical solution. The surface settlement caused by the tunnel excavation is obtained through the analysis of an example. The effects of disturbance strata and tunnel lining deformation are obtained by parameter analysis. The results show that the displacement curve of soil obtained by complex variable function is in good agreement with the measured data. The maximum settlement value of the ground surface is closer to the measured value, the depth and radius of the tunnel have great influence on the displacement of soil and the deformation of the lining, and the thickness of the lining has little effect on it, but it can not be ignored, the radial displacement curve of the lining is the duck egg shape of supine. With respect to 90 掳/ 270 掳axisymmetric, the crown and bottom are compressed, the compression of the vault is obviously greater than that of the arch bottom, the compression amount of the left and right sides is less than that of the upper and lower sides, which is shown as follows: after contraction, the compression is flattened to the left and the right side protrudes, and with the increase of the depth of burying, The annular displacement curve of the lining is apple-shaped with an axial symmetry of 0 掳/ 180 掳, and is zero at 90 掳and 270 掳. The absolute value of the circumferential displacement increases with the increase of the buried depth of the tunnel.
【作者单位】：国土资源部丘陵山地地质灾害防治重点实验室;上海理工大学环境与建筑学院;中国建筑科学研究院建筑安全与环境国家重点实验室;华东建筑设计研究院有限公司;
【基金】：国家自然科学基金项目(41772331) 上海自然科学基金项目(15ZR1429400) 国土资源部丘陵山地地质灾害防治重点实验室课题(2015k005) 建筑安全与环境国家重点实验室课题(BSBE2015-01)
【分类号】：U455.43

【相似文献】