【作者】 郭海防；

【导师】 张嘉凡；

【作者基本信息】 西安科技大学 ， 应用数学， 2010， 硕士

【摘要】 我国是世界上煤炭储量最丰富的国家之一,煤炭能源在国民经济发展中起着重要的基础作用。随着煤炭资源开采强度的不断加大,煤层开采效率越来越受到关注。水溶液对煤岩损伤弱化规律的研究是煤炭开采过程中的重大课题,由于我国急倾斜煤层分布广泛,因此水压力作用下对煤岩损伤弱化规律的研究更是对急倾斜煤层的开采方法优化的重要课题之一。本文以水溶液及孔隙水压力作用对煤岩体损伤弱化规律为主要研究对象。首先,通过水溶液对煤岩体强度损伤弱化的物理实验,得到了不同水溶液对煤岩含水率的改变不同及煤岩强度、弹性模量、泊松比与含水率的关系,试验表明:煤岩的强度、弹性模量随含水率的增加而减小,煤岩泊松比随含水率的增加而增大;其次,总结了水溶液对煤岩体力学性质三方面影响:从煤岩微元体强度服从Weibull分布的角度及密度、弹性模量变化的角度出发,建立了轴压与水压共同作用下煤岩体的统计损伤模型。引入孔隙水压力影响因子,证明孔隙水压力对煤岩体损伤情况。利用水压致裂理论,分析煤岩体孔隙水压作用原理,得出了煤岩裂纹初裂强度值,并对煤岩孔隙率进行了定性描述;最后,利用F-RFPA2D进行数值模拟,分析了孔隙水压力对煤岩加载损伤过程,对煤岩变形强度的影响,研究表明:当孔隙水压力恒定时,煤岩强度随围压的增加而增大;当围压相同时,孔隙水压力越高,煤岩强度越低。围压大小和起始水压力大小对孔隙水压力作用的影响显著。更多还原

【Abstract】 China coal reserves is one of the richest countries on the world, coal energy plays an important role in the development of national economy, with the coal resources exploitation strength increasing, coal mining efficiency has been paid more and more attention. Aqueous to coal and rock damage weakening is the important topic of coal mining process, Because China’s coal seam widely distributed, research the regularity of coal and rock damage to weaken under the action of water pressure is one of the important topics In steep coal seam mining method optimization.Based on the water pressure of coal and rock damage effect to coal and rock damage weakening as the main research object. First, through the physics experiment of aqueous to coal and rock mass strength damage reduction, get the relationship of the solution to the moisture content of different coal and coal rock strength changes, the elastic modulus and poisson ratio and the moisture content, Tests show: coal rock strength and elastic modulus decreases with the increase of the moisture content, petrographical poisson ratio increases with the moisture content; Secondly, summarizes the solution of coal and rock mechanics properties in three factors: Stress and strain characteristic, coupling of strength and solid-liquid. From angles of coal tiny intensity obey Weibull distribution and density, elastic modulus variation, establish statistical damage model of the axial compressive and pressure under the joint action of coal and rock. Introduced the pore water pressure influence factor, proof damage of pore water pressure to coal and rock. Using the theory of hydraulic fracturing to analyze the principle of pore water pressure effect to coal and rock, get coal and rock crack splitting strength value, and describe the coal and rock porosity, Finally, using the F-RFPA2D numerical simulation and analysis the pore water pressure to coal and rock damage process, influence to coal and rock deformation, Research shows that:When the pore water pressure constant, coal rock strength is increasing with confining pressure increases; When the same confining pressure, the higher of pore water pressure is, the lower of coal rock strength. Confining pressure size and size of water pressure on initial pore water pressure effect significantly.更多还原