可溶岩矿原位溶浸开采沉陷机理研究

项目名称： 可溶岩矿原位溶浸开采沉陷机理研究

项目编号： No.51504159

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 矿业工程

项目作者： 杨晓琴

作者单位： 太原理工大学

项目金额： 22万元

中文摘要： 可溶岩矿原位溶浸开采过程中矿体溶解形成溶腔，随着溶腔不断演化，逐渐失去对上覆岩层的支撑作用。在自重力作用下，上覆岩层产生向下弯曲变形导致地面沉陷。项目采用现场调研、理论分析、试验研究、数值模拟及模型建立、现场应用相结合的方法，研究钙芒硝可溶岩矿原位溶浸开采过程中不同开采条件下矿体及上覆岩层变形对沉陷的影响规律。试验研究溶浸液渗透压、浓度、温度耦合作用下钙芒硝可溶岩垂直层理的蠕变规律，并对蠕变前后钙芒硝试件进行显微CT扫描观测，试验研究钙芒硝矿上覆典型岩层在溶腔演化过程中的蠕变规律。通过试验数据和理论分析，建立蠕变本构模型，模拟沉陷规律，分析沉陷机理。在四川眉山区钙芒硝生产矿井进行现场应用，从岩石力学的角度分析原位溶浸采矿沉陷的机理规律，建立原位溶浸采矿沉陷预计模型。

中文关键词： 可溶岩；原位溶浸开采；多场耦合；蠕变模型；沉陷模型

英文摘要： In process of in-situ dissolution mining, dissoluable rock mineral can form cavity via rock dissolution，the supporting effect of rock on overlying strata is reduced gradually with development of cavity. Overlying strata bend downwards and this can lead ground to subsidence. The integrated methods, i.e. site surveys, theoretical analyses, experiments, and numerical simulations are used in the project. Model is established followed with its practical utilization to study effect laws of mineral deformation on overlying strata creep of glauberite, a sort of dissolvable rock mineral, under different mining conditions. Experiment is to study creep laws along direction vertical to glauberite beddings under coupling effect of osmotic pressure, density and temperature of the leaching solution. Moreover, specimens are conducted for micro CT scanning before and after creep experiment. Creep laws of typical overlying glauberite strata during cavity evolution are investigated through the experiments. Based on the experimental data and theoretical analyses, creep constitutive model is established, subsidence law is simulated and the mechanism of subsidence is analyzed. The results are put into application in glauberite production mines located in Meishan, Sichuan Province. The mechanism and rules of subsidence during in-situ dissolution mining are investigated from perspective of rock mechanics, by which subsidence projection model is constituted in in-situ dissolution mining.

英文关键词： dissoluble rock;solution mining in-situ;multi-coupled;creep model;subsidence model