劈裂注浆能耗分析

Energy Dissipation Analysis for Crack Grouting

假设土体服从摩尔库仑破坏准则,劈裂注浆的劈裂是指土体在注浆压力作用下压缩屈服和浆液的楔入。将压缩过程视为无限土体中的圆孔扩张问题,根据注浆过程中能耗区土体在注浆压力和静止土压力作用下的应力、应变和体变关系,以及注浆扩孔过程中的能量和体变守恒原理及土体的屈服准则,推导出劈裂注浆的初始启劈注浆压力求解公式。利用该求解公式计算的结果与现场试验结果较为吻合。从能量耗散角度,分析土体在劈裂注浆过程中的能量耗散,可以得出:劈裂注浆过程中主要的能量消耗在土体的劈裂、土体的裂缝延伸及土体的塑性变形上,其他方面的能量消耗相对较少。

On the assumption that the soil mass is in compliance with Mohr-coulomb failure criterion, crack grouting is the grout injection into the compressed and yielded soil mass under grouting pressure. The compression process is considered as the question of cavity expansion in infinite soil mass. According to the stress-strain-volume change relationships of the soil mass in energy dissipation area under grouting pressure and static soil pressure in the process of grouting, energy and volume change conservation principle and yield criterion, formula for computing the beginning grouting pressure caused by crack grouting is deduced. The calculation results obtained from this formula agree well with field test results. In the view of energy dissipation, energy dissipation of the soil mass during crack grouting process is analyzed. Analysis results show that the main energy is dissipated in crack, crack expansion and the plastic deformation of soil mass. Other dissipation is less compared with the above main energy dissipation.