锥探灌浆技术在小型水库大坝除险加固工程的应用探讨

Application of Cone Drilling Grouting Technique in Reinforcement Work of Small Reservoir Dams

为较经济解决某些小型水库均质土坝的严重渗漏问题,借鉴锥探灌浆技术在堤防防渗广泛应用经验,结合已实施的工程案例,通过地勘渗透试验分析和渗流稳定分析其合理性,并提出了实施要点:建议在水库坝高不大于20 m均质土坝,渗透系数、压实度均不满足土石坝设计规范要求且坝体渗漏量不大情况下,采用锥探灌浆技术较为适宜;灌浆应在坝前水位降至死水位后实施;应根据大坝的地勘报告、坝高和坝体渗流量等因素综合确定施工参数;施工中应设置大坝变形观测断面,实时监测大坝位移、沉降和检查变形、裂缝及冒浆情况。

In order to economically solve the serious leakage problem of homogeneous earth dams in some small reservoirs,the experience of extensive application of the cone drilling grouting technique in anti-seepage treatment of embankment is summarized.Based on practical engineering cases,the rationality of the technique is verified with geological exploration permeability tests and seepage stability analysis.Also,the key implementation points of the technique are concluded.It is recommended that the cone drilling grouting technique is more suitable for homogeneous earth dams with the dam height of no more than 20 m,and the permeability coefficient and compactness do not satisfy the requirements of the design specification,and the dam leakage is not large.The grouting construction should be carried out after the reservoir water level drops to the dead water level.The construction parameters should be determined based on a comprehensive consideration of the geological survey results,the dam height and the leakage flow of the dam body.During the grouting construction,dam deformation observation sections should be arranged to monitor the dam displacement and settlement and inspect the deformation,cracks and slurry emission conditions in real time.