【摘要】 为了探明煤系土开挖暴露后性能的劣化情况，借助特殊的制样方法，以多尺度试验结果揭示了煤系土随不同暴露时间其矿物质成分、微细结构和物理性质指标变化规律，并给出敏感性指标随暴露时间劣变的表达式.研究结果表明：煤系土暴露后成岩矿物含量降低，黏土矿物含量升高.随暴露时间增加，煤系土微细结构特征参数中，颗粒圆度降低，颗粒定向度增大，孔隙度和孔隙分布分维数增大，欧拉数减小，且均存在渐近线.敏感性物理指标中，黏粒含量增大，不均匀系数减小，塑性指数增大，且塑限存在“假塑性现象”，其变化规律均可用指数形式曲线描述.更多还原

【Abstract】 This study investigated the degradation of coal-bearing soil after excavation to understand its deteriorating properties. By employing a special sampling method,the research revealed changes in the mineral composition,microstructure,and physical properties of coal-bearing soil subjected to various exposure times. Expressions depicting the degradation of sensitive indicators over exposure duration were derived from multiscale experimental results. It was found that after exposure,the content of lithogenic minerals decreased while clay mineral content increased. With increased exposure time,certain microstructural characteristics exhibited trends:decreased particle roundness,increased particle orientation,amplified porosity and pore distribution fractal dimensions,and reduced Euler number,all showing asymptotic trends. Within sensitive physical indicators,the clay content increased,the coefficient of heterogeneity decreased,the plasticity index rose,with the plastic limit showing“pseudo-plasticity.”These changes followed exponential curves to describe their patterns.更多还原