侧向辐射注浆技术引起地表隆起变形分析

Analysis on Ground Heave Induced by Lateral Radiation Grouting Technique

侧向辐射注浆技术是用于处治现役高速公路沉降变形的新技术,可在通车条件下对高速公路进行加固。在通车条件下对高速公路进行加固需要对施工效应进行分析,确保施工过程中高速公路通车安全。根据土体中的球孔扩张理论,将侧向辐射注浆假设为半无限体多球孔扩张模型,将几何条件复杂的侧向辐射注浆简化为多球孔几何模型,并引入有限边界球孔扩张理论,建立注浆压力和扩孔半径的关系,得到了土体注浆过程存在极限注浆压力,在极限注浆压力后存在软化效应的结果;确定注浆球孔扩张压力和隆起变形的关系,最终给出了同时考虑注浆压力和注浆量两个注浆施工控制指标的地表隆起位移计算方法。结合工程实测参数,计算并对比分析了不同注浆压力、不同注浆步距对地表隆起位移的影响,给出了侧向辐射注浆施工隆起位移的计算方法,能够对注浆设计和施工提供指导作用。

Lateral radiation grouting technique is a new technology to treat the settlement of existing expressway by reinforcing ground while in operation.Grout casting effect needs to be analyzed to ensure traffic safety.Based on the spherical expansion theory for soil,a multiple spherical cavities expansion model was established to assume the grouting process as the half-space spherical cavity expansion.By simplifying the complex geometric condition of lateral radiation grouting as spherical expansion of multiple cavities,and by introducing the theory of spherical expansion to obtain the relation between grouting pressure and expansion radius,the conclusion was obtained that limit grouting pressure exists and softening effect can be found when grouting pressure reachs the limit.Then a method considering both grouting pressure and grouting volume was given to calculate the ground heave due to grouting.According to the field test data,calculation result was compared with the analyzed ground heave with different grouting pressure and grouting gaps.A calculation method for ground heave due to lateral radiation grouting was proposed to provide guidance for grouting design and construction.