【摘要】 盾构施工将会在管片和围岩之间形成环形空隙,对该空隙进行注浆回填来控制地层沉降是盾构施工控制地层位移的关键工序。注浆完成后随浆体水泥水化反应的进行和浆体水分的渗透损失,浆体体积收缩造成地层损失并引起地层位移沉降。因此壁后注浆体的变形及力学性质变化直接影响到土体的应力释放、土体位移及作用在管片上的土压力大小。利用自制壁后注浆单元模型试验装置,研究不同的注浆压力、注浆材料在砂性土条件下浆体的变形规律,提出了能够反映浆体变形规律的数学模型。确定间隙参数是解析方法预测土体位移的关键步骤,利用浆体变形模型可更为准确地确定壁后注浆完成后的盾尾间隙参数。更多还原

【Abstract】 An inevitable annular space named tail void is created at the rear of shield machines. This void is of importance with respect to subground settlements. During shield tunnel construction,the grout is being pumped in the void through a number of injection holes. With the hydration of cement and liquid loss after backfill process being completed,the grout volumes shrinkage leads to ground loss and induces the ground movement. The grout deformation and mechanical property variation can directly affect soil stresses releasing,ground movement, and earth pressures acting on segment. Utilizing the self-developed small scale element model of backfill grouting,the change laws of grout deformation are studied under different grouting pressures,different grout material mixtures in sandy soil. Based on grout deformation laws,mathematical model is proposed to simulate grout deformation. Identification of the gap parameter is one of the most important steps when using an analytical method to predict ground movement. Gap parameters can be obtained more exactly through grout deformation model.更多还原