Considering the situation of deep roadway of Juye mining area, of which the ground stress is high and the top coal is thick, and guided by the support idea, which is first anti-pressure, second pressure relief, third anti-pressure, high strength pressure relief anchor box beam(PRABB) support system was developed. PRABB support system has the advantage of low prestress loss, quantitative pressure relief, good supporting force transmission effects and a large contact area. Taking mine I-steel beam #12 and box support beam as trimmer beam respectively, two cross anchor beam support systems, two longitudinal single anchor beam support systems and two longitudinal double anchor beams support systems were designed. Taking deep thick top coal roadway of Zhaolou colliery as the engineering background, preliminary analysis of supporting effects of the support systems was produced by numerical test, and all the support systems were field-tested in crossheading of working face 3302. The field test results show that: (1) Six support systems are all better in controlling surrouding rock deformation than original support scheme. (2) Support effects of PRABB support systems are better than those of mine I-steel anchor beam support systems, and the roadway deformation of PRABB support systems is 15% - 25% less than that of mine I-steel anchor beam support systems. (3) Among all the support systems, the longitudinal single anchor beam support systems are best in controlling surrounding rock, the longitudinal double anchor beams support systems take second place, the cross anchor beam support systems are relatively poor. Control mechanisms of different arrangement modes of beams are analyzed by test results. By longitudinal single anchor beam support systems, deformation of key position in thick top coal roadway is controlled well; it is helpful in making the best of self-bearing ability of surrounding rock and controlling roof deformation. In the deep thick top coal roadway supporting, longitudinal single anchor box beam support system is better for controlling surrouding rock deformation in a cost-effective way; so that the supporting demand is satisfied.%针对巨野矿区深部高地应力厚顶煤巷道支护特点,以“先抗后让再抗”支护理念为指导,研制高强让压型锚索箱梁(PRABB)支护系统.该系统具有预紧力损失小、定量让压、支护力传递效果好、护表面积大等特点.分别以箱型支护梁和矿用12#工字钢为托梁设计了横梁、纵向单梁和纵向双梁共6种支护系统.以赵楼煤矿深部厚顶煤巷道为工程背景,利用数值试验对其支护效果进行初步分析,并在3302工作面顺槽进行6种支护系统的现场试验对比研究.现场试验结果表明:(1)相对于原支护方案,6种锚索梁支护系统均能有效控制巷道围岩变形；(2)PRABB支护系统试验段巷道支护效果整体优于工字钢锚索梁方案,前者围岩变形量比后者小15％～25％；(3)纵向单梁支护系统对巷道围岩的控制效果最好,纵向双梁支护系统次之,横梁支护系统相对较差.根据试验结果对钢梁不同布置方式的围岩控制机制进行分析表明:纵向单梁支护系统可有效控制厚顶煤巷道顶板关键部位的变形,调动围岩自承能力,使巷道变形得到较好控制.在深部厚顶煤巷道支护时,采用PRABB支护系统纵向单梁方案,可达到经济有效控制巷道围岩变形的目的.
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