Similar simulation test study on the influence of mining on shaft deflection of deep soil based on hydraulic permeability model

Abstract

Ensuring shaft safety is critical in the process of coal mining. During coal mining in the Guotun coal mine, Shandong Province, China, issues, such as shaft deflection, tank channel and shaft deformation, and tank jamming, which did not appear in the shaft before, brought huge hidden dangers to safety. In this study, a set of three-dimensional analog simulation systems for assessing the influence of mining on shaft deflection was designed by using penetration force simulations of gravity fields. In this system, electromagnetic displacement meter is used to collect surface settlement data, which verifies the feasibility of using hydraulic pillow to simulate formation disturbance caused by coal mining. the strain of the shaft is measured by optical fibers and strain gauges, and the amount that mining influenced the deflection of the shaft is obtained. The results show that there is an approximately positive linear correlation between the horizontal displacement of the shaft caused by mining and the mining thickness of the coal. The horizontal displacement of shaft caused by coal mining is inversely proportional to the moving Angle within a reasonable range. The horizontal displacement of shaft is affected by mining mode, and symmetrical mining can significantly reduce the horizontal displacement of shaft. The horizontal displacement of the shaft at different depths caused by mining decreases with increasing shaft depth, which is the main cause of shaft deflection.

Study on the Vertical Stability of Drilling Wellbore under Optimized Constraints

“…The wellbore structure is prone to longitudinal instability during the construction process in drilling methods. Once the wellbore structure loses its stability, it can lead to collapse accidents, causing significant personnel and economic losses [6][7][8][9][10]. Moreover, the depth of coal resource extraction in western China is gradually increasing, and the construction depth of new shafts is about to reach a historic height [11,12].…”