盾构隧道壁后注浆浆液时变半球面扩散模型

Half spherical Surface Diffusion Model of Shield Tunnel Back filled Grouts

摘要:

在假定注浆浆液为粘度时变性流体且浆液沿半球面扩散的前提下，应用达西定律对盾构管片注浆扩散半径及浆液对管片产生的压力进行了理论推导，得到了浆液扩散半径及对管片产生的压力的计算式.通过具体实例，对比分析了考虑浆液粘度时变性和不考虑浆液粘度时变性2种条件下注浆压力、注浆时间、浆液初始粘度、土体渗透系数对浆液扩散半径及浆液压力的影响，得到了浆液压力的分布形式.分析结果表明，注浆压力和土体渗透系数较大且注浆时间较长时，浆液的粘度时变性对浆液扩散范围和压力的影响显著；可通过调整注浆压力、注浆时间、浆液特性来调整注浆效果.

Abstract:

On the assumption that the back filled grouts should be viscosity degeneration fluids, and the grouts diffuse with half spherical surface, the grouts diffusion area and the pressure to shield tunnel segments were derived with Darcy’s law. As a result, the formula to calculate the radius and the pressure were acquired. The diffusion radius and the pressures to shield tunnel segments with different grouting pressures, grouting time, grouts initial viscosities, and soil permeability coefficients were compared between the grouts viscosity degeneration condition being taken into consideration or not. The diffusion model of grouts pressure is also acquired. The result shows that the grouts viscosity degeneration has a significant influence on the diffusion radius and the pressure to shield tunnel segments on the condition of high grouting pressure, long grouting time, and big soil permeability coefficient. The grouting effect can be improved by adjusting grouting pressure, grouting time and grouts properties.