岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2014年
2期
413-422
,共10页
陈璐%谭云亮%臧传伟%赵同彬%于凤海
陳璐%譚雲亮%臧傳偉%趙同彬%于鳳海
진로%담운량%장전위%조동빈%우봉해
加锚岩石%力学试验%裂纹扩展%破坏形态
加錨巖石%力學試驗%裂紋擴展%破壞形態
가묘암석%역학시험%렬문확전%파배형태
anchored rock%mechanical test%crack propagation%failure mode
采用煤矿煤层顶板岩石作为加锚基体,用钢丝模拟锚杆,对由二者组成的加锚岩石进行了巴西劈裂、单轴压缩和压剪试验研究。结果表明,当加锚试件岩石基体出现塑性屈服裂纹开始扩展后,锚杆逐渐取代岩石基体成为外荷载的承载主体,试件的破坏特征由脆性向延性转变。加锚试件劈裂过程中,圆盘中心出现裂缝后,部分试件仍具有一定的承载能力,其抗拉强度提高了51.1%;另有部份试件则表现为迅速破坏并丧失承载能力,其抗拉强度提高了91.6%。单轴压缩试验中,加锚试件的破坏形式可分为两类:一类为裂纹平行锚杆轴向发展;另一类为裂纹垂直锚杆轴向发展,加锚试件的抗压强度提高了34.6%。加锚试件剪切过程中,其承载能力出现了明显的二次劣化现象,回归试验结果可得加锚试件的内摩擦角基本不变,而凝聚力提高了22.9%。
採用煤礦煤層頂闆巖石作為加錨基體,用鋼絲模擬錨桿,對由二者組成的加錨巖石進行瞭巴西劈裂、單軸壓縮和壓剪試驗研究。結果錶明,噹加錨試件巖石基體齣現塑性屈服裂紋開始擴展後,錨桿逐漸取代巖石基體成為外荷載的承載主體,試件的破壞特徵由脆性嚮延性轉變。加錨試件劈裂過程中,圓盤中心齣現裂縫後,部分試件仍具有一定的承載能力,其抗拉彊度提高瞭51.1%;另有部份試件則錶現為迅速破壞併喪失承載能力,其抗拉彊度提高瞭91.6%。單軸壓縮試驗中,加錨試件的破壞形式可分為兩類:一類為裂紋平行錨桿軸嚮髮展;另一類為裂紋垂直錨桿軸嚮髮展,加錨試件的抗壓彊度提高瞭34.6%。加錨試件剪切過程中,其承載能力齣現瞭明顯的二次劣化現象,迴歸試驗結果可得加錨試件的內摩抆角基本不變,而凝聚力提高瞭22.9%。
채용매광매층정판암석작위가묘기체,용강사모의묘간,대유이자조성적가묘암석진행료파서벽렬、단축압축화압전시험연구。결과표명,당가묘시건암석기체출현소성굴복렬문개시확전후,묘간축점취대암석기체성위외하재적승재주체,시건적파배특정유취성향연성전변。가묘시건벽렬과정중,원반중심출현렬봉후,부분시건잉구유일정적승재능력,기항랍강도제고료51.1%;령유부빈시건칙표현위신속파배병상실승재능력,기항랍강도제고료91.6%。단축압축시험중,가묘시건적파배형식가분위량류:일류위렬문평행묘간축향발전;령일류위렬문수직묘간축향발전,가묘시건적항압강도제고료34.6%。가묘시건전절과정중,기승재능력출현료명현적이차열화현상,회귀시험결과가득가묘시건적내마찰각기본불변,이응취력제고료22.9%。
With rock sample of coal seam roof as matrix and steel wire as bolt, anchored rocks have been experimented by means of uniaxial compression, Brazilian split and pressure-shear test. The results show that: when rock matrix comes up against plastic yielding and certain cracks begin to extend, anchor bolt gradually becomes the main carrier of external load and rock's failure characteristics also change from fragility to ductility. During the process of splitting disk samples, a certain crack in the center of part of samples have no obvious impacts on carrying capacity;its strength increases by 51.1%. A huge penetrating crack turns up in other parts of samples and it quickly loses the carrying capacity; its strength increases by 91.6%. Failure forms of uniaxial compression samples can be divided into two categories. The first is failed with cracks propagating parallel with bolt;and the second is failed with cracks propagating vertically with bolt; the strength of anchored rock increases by 34.6%. In the pressure shear test, the carrying capacity of anchored samples obviously deteriorates once again; and the result shows that its internal friction angle of anchored samples isn't changed while the cohesive force rises by 22.9%.