顶板诱导崩落预裂钻孔裂隙发育监测与分析

基于连续采矿的项板诱导崩落技术是一种主要应用于大型倾斜、缓倾斜贫矿体的非传统、安全高效的采矿与空区处理技术。为研究岩体内节理、裂隙等不连续结构面的发育与围岩诱导崩落机制的关系，采用前视全景钻孔电视对项板诱导崩落预裂钻孔孔壁进行监测，获得人为扰动下岩体内各种原生裂隙与不连续结构面发育情况，为诱导崩落的可行性研究提供定性与直观的评价，从而提高顶板诱导崩落的可控性。监测与分析结果表明，在项板诱导崩落过程中，直接顶板以上5m范围内出现一个破碎带，围岩的结构成为碎裂状；在顶板上方10m范围左右，出现一个圆形裂隙环带。随着裂隙的进一步发展，项板裂隙带密度增加，最终形成项板的诱导崩落。

MONITORING AND ANALYSIS OF FRACTURE DEVELOPMENT IN PRE-SPLITTING HOLE OF CAVE INDUCEMENT OF ROOF

Based on continuous mining technology, cave inducement of roof is a nontraditional, safe and high-efficiency method, which is widely used in mining of inclined, gently inclined large-scale barren orebody and processing technique to mined stope. In order to study the relationship between the evolvement of fracture and discontinuity in rock mass and mechanism of cave inducement of rock mass, the monitoring on development of fracture on the wall of pre-splitting boreholes in cave inducement of roof is put into practice by panoramic borehole television. According to monitoring results, the development situation of original fracture and discontinuity in rock mass under the artificial disturbance is reflected by the images. Consequently, a qualitative and intuitional evaluation to cave inducement can be provided; and the controllability of cave inducement roof is increased. The monitoring and analytical results show that a fractured zone comes into being in the range of 5 m in the direct roof during the cave inducement process. Relatively, the surrounding rock represents fragmentation circumstance. A ring-shaped fracturing zone is formed in the range of 10 m from the roof simultaneously. Then, with the farther development of quantity and density of fracture, the cave inducement of roof is formed ultimately.