天然碱矿双水平溶腔稳定性分析及安全矿柱宽度探讨

Stability Analysis on the Two-horizonal Dissolved Champers of Trona Mine and Discussion on the Width of Safety Pilllar

土耳其Kazan天然碱矿采用钻井与对接井技术使两井或多井连通,形成水平溶采通道并进行注水开采。以土耳其Kazan天然碱矿为例,采用FLAC3D软件对油垫水溶法所形成的双水平溶腔形状进行简化,通过改变双水平溶腔间的矿柱宽度进行溶腔稳定性分析,并最终对安全矿柱宽度的确定进行了相关探讨。研究表明:溶腔顶板塑性区分布范围呈现正三角形分布形态,当矿柱宽度为25m时,溶腔上部顶板及肩部塑形分布区均明显减小;溶腔应力与位移的变化随着矿柱宽度增大至25m时逐渐趋于平缓;矿柱宽度的大小对溶腔底部隆起的影响基本可忽略。

The drilling and butted well technology in Kazan trona mine of Turkey was used to connect wells, so as to form a horizontal dissolved mining channel and conduct water flooding mining. Taking the Kazan trona mine in Turkey as an example, the two-horizontal dissolved champers shape by oil cushion solution salt was simplified by FLACSD, and through changing the pillar width of the two＇horizontal dissolved champers, the stability of champers was analyzed, then the determination of the width of the safety pillar was discussed. The results showed that, the plastic area distribution at the roof of dissolved champers presented a positive triangular pattern. When the pillar width was 25 m, the plastic distribution area at the upper roof and shoulder of the chambers obviously reduced. The change of stress and displacement of ehampers showed a gentle trend as the width of the pillar was increased to 25 m, so the effect of the pillar width on the rise in bottom of dissolved champers could be negligible.