基于SPH的类矩形盾构同步注浆扩散机制及参数获取

Diffusion Mechanism and Parameters Acquisition of Quasirectangular Shield Synchronous Grouting using SPH Method

摘要:

异型盾构由于自身断面几何形状的特殊性，需要对其同步注浆的扩散效果及参数控制进行深入研究.利用光滑粒子流体动力学（SPH）方法对国内第1条类矩形盾构法隧道工程中同步注浆扩散机制和参数获取进行研究.分析结果表明，浆液扩散模式具有纵环向相互关联的挤压填充性流动特征，其在盾构顶/底部填充效率较差；高流动度和早强高抗剪性浆液的扩散面弧度与压力损失率效果以及整环流动封闭效率和填充均匀度都优于液态浆和抗剪浆；注入率150%对周边环境的扰动程度最小，上下孔位浆液注入比为4∶3∶2∶1的注浆效果最好，体现为浆液压力分布更均匀；而考虑较快的闭合/充盈时间可以认为对称孔位布置更适合类矩形盾构同步注浆施工.

Abstract:

Due to the particularity of heterotype shield, further research need to be executed on grouting diffusion effect and control parameters. This diffusion mechanism and parameter acquisition were studied using smoothed particle hydrodynamics (SPH) for the first quasirectangular shield tunneling project in China. The results show that the grout diffusion pattern has an related squeezing filling property in longitudinal and ring direction, and its filling efficiency is poor at top/bottom of the shield; The grout diffusion surface curvature, grouting pressure loss rate, entire flow sealing efficiency and filling uniformity of rectangular grout are better than these situation of liquid grout and thick grout; The disturbance degree of 150% injection rate for the surrounding stratum environment is minimal, and the optimum effect with grout injection ratio is 4∶3∶2∶1, which reflects in pressure distribution is more uniform; And considering the filling time, it is suggested that the symmetrical hole position is more suitable for synchronous grouting.