非均质断层破碎带注浆扩散机理

断层破碎带是诱发塌方、突泥等地质灾害的重要构造因素。但是，针对断层治理的注浆理论与技术研究进展缓慢。结合断层岩体特征分析与注浆试验，开展断层破碎带注浆扩散过程与规律研究。首先，依托永莲隧道F2断层突水突泥灾害注浆治理工程，提取并分析断层岩体性质，划分岩体类型，建立注浆概念模型，将岩体划分为松散型、软弱型及密实型等三种介质。基于牛顿流体及土体一维压缩理论，分别建立三种介质注浆控制方程，分析介质结构特征与孔隙度、压缩性等物理性质，对注浆扩散过程的影响规律。结合注浆试验，研究了不同介质条件下，注浆过程中注浆压力、介质应力变化规律，基于浆脉分布情况，分析浆液由注入点向介质的扩散过程。理论分析与试验结果表明：非均质断层破碎带注浆扩散过程，可分为优势充填与劈裂扩散两个阶段，注浆压力变化曲线由缓慢上升至陡降的突跳点即两阶段分隔点；优势充填阶段主要发生在松散型与软弱型介质中，注浆压力上升慢，浆液出现集中扩散；劈裂扩散阶段主要发生在密实型介质中，注浆压力上升快，扩散范围与介质结构面数量正相关，与压缩模量、注浆速率负相关。针对松散型与软弱型介质形成的不良地质区，为达到优势扩散与治理效果，提出了定域注浆控制技术，并在永莲隧道突水突泥灾害治理工程中应用，取得了良好的注浆治理效果。

Grouting Diffusion Mechanism in Heterogeneous Fault-fracture Zone

The fault-fracture zone is an important tectonic factor for the geological hazards such as cave-in and mud bursting. However, the research on grouting theory and technology of fault treatment develops slowly. We carried out the research of grouting diffusion process and rule in fault-fracture zone, based rock mass analysis and grouting test. Firstly, property of rock mass in fault-fracture zone was analyzed, based on the treatment project of F2 fault water-and-mud inrush hazard in yonglian tunnel. The rock mass was classified into three kinds of medium: incompact, compressible and compact, and the grouting conceptual model was established. The grouting control equations of three kinds of medium were built, to analysis the influence on grouting process by rock mass property, such as: texture, porosity and compressibility. Through the grouting test, the variation law of grouting pressure and media stress was studied, and the slurry diffusion process from borehole to the media was analyzed, based on the distribution of slurry vein. The theoretical and experimental results show that: the grouting diffusion process in heterogeneous fault-fracture zone could be divided into two stages: advantage filling and split grouting, and the curve break of grouting pressure from creeping up to sharp down. The advantage filling stage, in which the slurry intensively diffuses and the grouting pressure increasing slowly, occurs mainly in compressible and compact media. In the split grouting stage which occurs mainly in incompact media, the grouting pressure rises fast, the grouting diffusion distance is positively related to the number of rock mass structural planes, and negatively related to the compression modulus of rock mass and grouting rate. In order to realize the advantage diffusion of slurry in the treatment process of unfavorable geologic bodies filled with incompact or compressible medium, the grouting control technique was put forward, and applied to the treatment project of F2 fault water-and-mud inrush hazard in yonglian tunnel, the technique was proved to have good grouting treatment effect.