地下工程涌突水注浆止水浆液扩散机制和封堵方法研究

RESEARCH ON MECHANISM OF GROUT DIFFUSION OF DYNAMIC GROUTING AND PLUGGING METHOD IN WATER INRUSH OF UNDERGROUND ENGINEERING

涌突水是地下工程的主要地质灾害之一。实践表明,注浆是治理涌突水的有效技术手段,但相关的动水注浆理论发展尚不成熟,尤其是裂隙动水条件下的浆液扩散和封堵机制研究不足。针对上述问题,研发准三维裂隙动水注浆模型试验台,进行裂隙岩体涌突水的动水注浆模型试验研究,通过对200余组试验数据进行分析,提出浆液的U形扩散规律和水泥浆液的分层分区扩散机制,得到浆液的快速析水沉积原理和沉积留核扩散规律,实现浆液扩散和封堵效果的定量评价。在此基础上,形成以浆水流量比为核心控制因素的裂隙涌水注浆封堵方法。室内涌水注浆封堵试验和龙固煤矿高压涌水现场注浆封堵试验进一步验证研究成果的正确性,这对发展动水注浆理论和指导工程实践有一定作用。

Grouting has been indicated to be an effective technological means to manage water inrush, which is one of the major geological hazards in underground engineering. However, the dynamic grouting theory, especially the mechanisms of grout diffusion and plugging of fracture in hydrodynamic condition, are not studied systematically and meticulously. In order to evaluate the dynamic grouting for plugging water inrush from fractured rock mass, a quasi-3D fracture model test-bed is developed. Through analyzing 218 groups of dynamic grouting tests data, U-shaped diffusion law and：the sectionalized and layered diffusion mechanism of grout are proposed. The principle of fast water-separating and the mechanism of depositing-core diffusion are studied. Quantitative evaluations of grout diffusion and plugging effect are realized. Based on the research above, a new technology of plugging water inrush, with the controlling factor RGW（ratio of grout injection to water discharge through unit width of fracture per unit time）, is put forward. The practical effect of research results is verified through the model test and field test in Longgu coal mine. The research results may play a promoting role in developing dynamic grouting theory and guiding engineering practice.