冲积层中劈裂注浆现场模型试验

Experiment of Fracture Grouting in Alluvium with Physical Model

河流堤坝多位于深厚冲积层上,而冲积层含砂石量大等特点对堤坝防渗、稳定性是不利的,对堤坝进行注浆加固是必要的,而研究浆液在冲积层中的分布扩散规律是首要任务.基于传统注浆理论,通过现场注浆模型试验,得出浆液在冲积层中的分布扩散规律、浆液劈裂机理、土的加固特性以及注浆加固过程中应注意的问题.指出浆液在冲积层中一般先沿土石分界面进行充填、劈裂,并以水平向劈裂为主.在注浆过程中宜采用多次重复注浆方式以达到提高加固效果的目的.对冲积层中堤坝注浆加固有一定的参考与指导作用.

Dams are mainly located at the deep alluvium, where large amount of sand and gravel is adverse to prevention of seep- age and maintenance of stability of the dams. Therefore it is necessary to reinforce the darns by grouting, and the primary task is to do research on the laws of diffusion and distribution of the slurry in the alluvial layer. The present study is based on the traditional theory of grouting and the laws of diffusion and distribution of the slurry, the slurry splitting mechanism, the char- acteristics of soil reinforcement are obtained. In addition, it is found by on-site grouting model tests that the slurry is generally filling and splitting along the interface between the earth and rock, and mainly splitting in the horizontal direction in grouting reinforcement process. To improve the reinforcement effect, the repeated injection should be adopted in grouting process. The study results will facilitate future dam grouting reinforcement projects in alluvial layer.