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为了研究含水率对层状岩体劈裂抗拉强度的影响,特选取层理显著的砂岩为研究对象,考虑5种含水率,进行顺层理弱面的劈裂抗拉强度试验,结合岩样劈裂破坏面的微观形貌特征和能量参数变化规律进行综合分析。研究结果表明:(1)随着含水率的增加,层状砂岩的抗拉强度逐渐减小,总体呈现先陡后缓的降低趋势,在饱水度低于80%左右时,抗拉强度降低幅度明显较大,而后抗拉强度降低趋势逐渐趋于缓慢;(2)岩样劈裂破坏面的高度参数和纹理参数都随着饱水度的增加而逐渐增大,呈先陡后缓的增长趋势,岩样抗拉强度与劈裂面微观形貌参数存在较好的线性相关性;(3)随着含水率的增加,加载过程中岩样吸收的总能量、弹性应变能逐渐减小,呈现与抗拉强度类似变化趋势,弹性应变能占总能量的比值逐渐减小,耗散能占总能量的比值逐渐增大;(4)层理弱面既是层状岩体结构的薄弱面,也是水分吸收和运移的主要空间和通道,含水率增加,首先是影响岩样层理弱面力学性状和孔隙水的分布,改变岩样加载过程中的裂纹扩展规律,进而影响加载过程中的弹性应变能和耗散能的分配比例,从而导致岩样劈裂破坏面形态趋于复杂,抗拉强度降低,水对岩样抗拉强度的影响是一个从微观结构变化导致宏观力学特性劣化的过程。
In order to study the influence of water content on the splitting tensile strength of stratified rock mass, sandstone with obvious stratification is selected as research object. The splitting tensile strength test of stratified stratified weakness is carried out considering five kinds of water content. Like splitting and destruction of the micro-morphological features and energy parameters of a comprehensive analysis of changes. The results show that: (1) With the increase of water content, the tensile strength of layered sandstone decreases gradually and then decreases steeply and slowly. When the water saturation is lower than 80%, the tensile strength decreases (2) The height and texture parameters of the fractured and fractured surface of the rock mass gradually increase with the increase of water saturation, which shows a steep and slow (3) With the increase of moisture content, the total energy absorbed by the rock samples during loading and the elastic strain energy can be gradually reduced , Showing a trend similar to that of tensile strength. The ratio of elastic strain energy to total energy gradually decreases and the ratio of dissipative energy to total energy increases gradually. (4) The layer weakness is not only the weakness of the layered rock mass structure , Which is also the main space and channel for moisture absorption and migration. The moisture content increases. The first is the influence of the mechanical properties of the weak surface and the distribution of pore water in the rock sample layer, and the change of the crack propagation law during the loading of the rock sample, thus affecting the loading process The elastic strain energy and dissipative energy distribution ratio, thus guide Splitting rock sample fracture surface morphology tends to be complex, tensile strength falls, the effect of water on the tensile strength of the rock sample is a process leading to the deterioration of the mechanical behavior from the structural change of microstructure.