鲁中矿区地下开采对竖井井塔楼的影响分析

INFLUENCE OF UNDERGROUND MINING ON SHAFT TOWERS IN LUZHONG MINING AREAS

针对鲁中矿区软岩地层地下开采引起岩体移动变形及竖井井塔楼倾斜变形的工程实际情况,将该矿区深埋金属矿体开采引起的岩体移动变形这一客观现象视为一随机事件,建立了开采岩体移动分析数学模型,并利用该模型对开采引起采区岩体移动变形及竖井井塔楼所处地表移动变形进行了具体计算分析。分析结果表明,理论预测值和工程实际观测结果吻合很好;在软岩地层条件下,矿体开采地表移动变形的影响范围有随着采深的增加而逐渐增大的趋势。这些结果可用于矿山竖井及井塔楼的安全评价。

Prediction of ground movements and their surface effects is an important problem of the rock mass mechanics in the excavation activities, especially the ore mining in soft rock mining areas. Whether planned or accidental, such movements can cause considerable damage to structures located within the area of influence of underground mining works. Example is the recent subsidences that took place at the end of the 1990s in the Luzhong mining areas. A better understanding is necessary on how ground surface movements can be imparted to the supported structure and damages it. Based on the results of the statistical analysis of a large amount of measured data in mining engineering, the fundamental theoretical model of ground surface movements due to underground mining is established by using the theory of probability. The formulas of rock mass displacements and deformations are developed and applied to the prediction of the ground surface movements due to underground mining. The agreement of the theoretical results with the field measurements shows that the proposed model is satisfactory and the formulae obtained are valid; and thus can be effectively used for analyzing and predicting the ground surface movements due to underground mining in soft rock mining areas. The results show that the area of rock mass displacements and deformations in overlying strata will deteriorate with the increase in depth. The results can be used for safety assessment of shaft and the towers.