岩石力学与工程学报
巖石力學與工程學報
암석역학여공정학보
CHINESE JOURNAL OF ROCK MECHANICS AND ENGINEERING
2014年
3期
458-467
,共10页
许江%苏小鹏%程立朝%王雷%刘婧%冯丹
許江%囌小鵬%程立朝%王雷%劉婧%馮丹
허강%소소붕%정립조%왕뢰%류청%풍단
岩石力学%压剪试验%细观裂隙%运移通道%原生裂隙%坚硬颗粒
巖石力學%壓剪試驗%細觀裂隙%運移通道%原生裂隙%堅硬顆粒
암석역학%압전시험%세관렬극%운이통도%원생렬극%견경과립
rock mechanics%compression-shear test%meso-cracks%migration pathways%original cracks%hard granule
利用自主研发的煤岩细观剪切加载试验装置,开展压剪应力作用下含瓦斯原煤细观裂隙动态演化特征试验研究,描述瓦斯运移通道的形成过程并分析影响细观裂隙形态特征的因素。研究结果表明:裂隙演化为瓦斯入渗煤体并在煤体中运移提供通道;在瓦斯压力及压剪应力的共同作用下,煤体表面破碎、脱落,破碎区更容易演化出新的裂隙。原生裂隙和坚硬颗粒都对细观裂隙演化产生影响:原生裂隙处更容易演化出新裂隙,从而在局部区域形成H型裂隙结构,且新裂隙与原生裂隙交汇时发生移动错位;坚硬颗粒则使得裂隙分叉并绕过自身演化,使得张拉和剪切共同作用形成细观裂隙,裂隙分叉角度为10°~100°,分叉角离散性大;原生裂隙与坚硬颗粒都使得压剪过程中瓦斯在煤体中运移的数目增多。随着法向应力的增大,加上初始损伤和坚硬颗粒的影响,裂隙分布率增大,煤体表面破碎越剧烈。
利用自主研髮的煤巖細觀剪切加載試驗裝置,開展壓剪應力作用下含瓦斯原煤細觀裂隙動態縯化特徵試驗研究,描述瓦斯運移通道的形成過程併分析影響細觀裂隙形態特徵的因素。研究結果錶明:裂隙縯化為瓦斯入滲煤體併在煤體中運移提供通道;在瓦斯壓力及壓剪應力的共同作用下,煤體錶麵破碎、脫落,破碎區更容易縯化齣新的裂隙。原生裂隙和堅硬顆粒都對細觀裂隙縯化產生影響:原生裂隙處更容易縯化齣新裂隙,從而在跼部區域形成H型裂隙結構,且新裂隙與原生裂隙交彙時髮生移動錯位;堅硬顆粒則使得裂隙分扠併繞過自身縯化,使得張拉和剪切共同作用形成細觀裂隙,裂隙分扠角度為10°~100°,分扠角離散性大;原生裂隙與堅硬顆粒都使得壓剪過程中瓦斯在煤體中運移的數目增多。隨著法嚮應力的增大,加上初始損傷和堅硬顆粒的影響,裂隙分佈率增大,煤體錶麵破碎越劇烈。
이용자주연발적매암세관전절가재시험장치,개전압전응력작용하함와사원매세관렬극동태연화특정시험연구,묘술와사운이통도적형성과정병분석영향세관렬극형태특정적인소。연구결과표명:렬극연화위와사입삼매체병재매체중운이제공통도;재와사압력급압전응력적공동작용하,매체표면파쇄、탈락,파쇄구경용역연화출신적렬극。원생렬극화견경과립도대세관렬극연화산생영향:원생렬극처경용역연화출신렬극,종이재국부구역형성H형렬극결구,차신렬극여원생렬극교회시발생이동착위;견경과립칙사득렬극분차병요과자신연화,사득장랍화전절공동작용형성세관렬극,렬극분차각도위10°~100°,분차각리산성대;원생렬극여견경과립도사득압전과정중와사재매체중운이적수목증다。수착법향응력적증대,가상초시손상화견경과립적영향,렬극분포솔증대,매체표면파쇄월극렬。
Using self-developed meso-shear test equipment for coal and rock containing gas,tests of raw coal containing gas under compression-shear stress were carried out to study the meso-cracks′dynamic evolution. The formation of gas migration pathways is described;and the factors influencing meso-morphological characteristics of cracks are analyzed. The results show that the evolution of cracks provides pathways for gas migration in coal continuously. Coal surface crushes and then drop as the gas pressure and compression-shear stress on coal simultaneously. The fractured zone has more initiations of cracks conversely. Both the horizontal original cracks and hard granules have effects on the meso-cracks;cracks initiate more easily when encounter the original cracks;then the newly formed cracks and the original cracks together make the composition of an H-shaped one locally. There is also always a dislocation for newly formed cracks subjected to the original cracks. The evolution directions of cracks change because of the existence of hard granules which are always bypassed,the bifurcation angles range from 10°-100°which shows obvious discreteness and meso-cracks are formed by tension and shear together.There are more pathways for gas migration as the existence of original cracks and hard granules. Both the fracture distribution rate and coal crushing extent increase as the normal stress increases and the effect of initial damages and hard granules.