Stability analysis and grouting treatment of inclined shaft lining structure in water-rich strata: A case study

The stability of inclined shaft lining structure (ISLS) in complex water-rich strata is affected by many factors, such as water pressure, joint, soft rock, lining corrosion and so on. The instability of the ISLS will affect the safe and efficient coal mine production. Bathe sed on the geological conditions of the Xiaobaodang coal mine, this paper tested the evolution characteristics of concrete composition in long-term water seepage areas and revealed the influence mechanism of corrosion weakening of shaft lining (SL) in water-rich strata. Meanwhile, transient electromagnetic, ground penetrating radar, and infrared monitoring are used to detect the water-rich zones, and damage zones of surrounding rock and lining water seepage zones, and a three-level safety evaluation model for the instability risk of ISLS is constructed. Water abundance of the surrounding rock, surrounding rock deterioration, and shaft lining seepage were the specific indicators in the model. The main inclined shaft (MIS) in the studied coal mine is divided into three levels: non instability risk zone, potential instability risk zone, and high instability risk zone. According to the evaluation results, comprehensive prevention and control measures of “hydrophobic hole drainage” and “back-lining grouting” are adopted for the water inrush source and the surrounding rock micro-crack water channel. The precise prevention and control of ISLS is realized. The research results also provide a reference for the stability evaluation of ISLS and the accurate prevention and control under similar conditions.