考虑注浆材料流变的隧道施工土层变形计算

Deformation calculation of soil surrounding tunnel considering rheology of grouting material

在盾构隧道施工过程中背后注浆是必不可少的,注浆材料在逐步卸载的压力作用下由流动状态变化到固体状态,注浆材料的变形特性将与恒载作用有区别。针对南京地铁1号线实际工程盾构隧道施工注浆材料,进行了卸载条件和恒载条件下注浆材料的流变试验,得到了非线性流变的试验曲线和拟合的流变方程;在半无限空间圆孔扩张位移理论解和注浆材料的流变试验结果的基础上,推求得到隧道所在土层的位移解,确定了位移的影响范围,讨论了地表沉降计算结果的合理性,初步建议确定隧道施工应保护区域的确定原则。

It is necessary to inject grout in shield back in construction process of tunnel by shield driving method. The grouting material is from liquid to solid on stepped unloading pressure. The characteristics of grouting material is different from that on constant load. On basis injection material in tunnel of Nanjing subway No 1 with shield driving method, creep tests of injection material under constant loading and unloading condition have been taken, the rheological equation and nonlinear experiment curves have been shown. Based on analytical solution of spherical expansion in semi-space and rheological test of injection material the displacement solution of soil surrounding tunnel has been presented; influence＇ area from deformation is discussed; the feasibility of calculation is analyzed. The determination method of protection from tunnel construction is suggested.