宜昌磷矿地压显现规律及数值模拟

Regularity and mechanism of ground pressure in Yichang phosphate mine

在调查宜昌神农、樟村坪、桃坪河等磷矿的地压显现情况的基础上,总结了宜昌磷矿地压显现规律,主要表现为:顶板易发生不规则块体冒落、板状冒落、窝状冒落、顶板下沉等破坏现象;矿柱易发生片落(或剥落)式破坏、劈裂破坏、剪切破坏,以及这些破坏形式的组合;底板易发生鼓胀及开裂变形.利用离散元软件3DEC,结合研究区工程地质条件,分析了宜昌磷矿地压显现机理,认为引起地压活动的原因可归纳为内因和外因两个方面.其中,矿山岩体赋存的地应力条件、地质构造及岩体结构是决定地压活动规律的内因,矿山开采活动、地下水是控制地压活动形式及剧烈程度的外因.建议因地制宜,选择合理的开采方式,并加强地压及变形监测.

Based on field investigation to the characteristic of strata behaviors in Yichang phosphate mining area,such as Shennong, Zhangcunping, Taopinghe, the regularity of ground pressure behaviors was summarized that irregular block caving, tabular caving, fossa caving and roof subsidence are usually in the roof, spalling, splitting, shearing and the combination of these failure modes are usually in the ore pillar, and bulging, cracking in the floor. Failure mechanism of appearance of Yichang Phosphate Mine was analyzed, combined with the field engineering geological condition by using 3DEC. The results show that the reasons caused strata behaviors can conclude and summarize as two aspects, namely internal and external causes, ground pressure condition of rock mass occurrence, geological structure and rock mass structure are internal causes that determine the regularity of ground pressure; mining activities and underground water are external causes that control the activity forms and extent of ground pressure regularity. It is suggested that appropriate exploitation mode should be adopted according to local conditions and the monitoring pressure and deformation of ground should be strengthed.