State Key Laboratory Breeding Base for Mining Disaster Prevention and Control College of Resources and
Environmental Engineering, Shandong University of Science and Technology

为研究岩石尺寸效应对冲击倾向性测试结果的影响,进行了高径比相同,直径区间为25~75mm的细砂岩试件的单轴抗压强度试验和颗粒流模拟分析。试验结果表明:小尺寸试件抗压强度较低,声发射产生时间较早、数量较多,峰前积聚能量较小;峰后为塑性失稳、劈裂破坏,能量释放速度较慢,冲击能量指数较小,冲击倾向性较弱;大尺寸试件抗压强度较高,声发射事件数量较少,并且主要集中在极限载荷附近,峰前积聚能量较大,峰后为脆性失稳、剪切破坏,能量迅速释放,冲击能量指数较大,有较强的冲击倾向性;得到了不同尺寸试件的冲击能量指数修正系数,减小了尺寸效应对冲击倾向性测试结果的影响。

In order to research the influence of size effect on bump- prone test results, laboratory uniaxial compressive strength tests and numerical simulations we re applied to analyze different size specimens which the ratio of height and diameter was same and the interval of diameter was between 25 ~ 75 mm. The results show ed that the smaller size specimenDs compressive strength was low. The acoustic emission happened early with a great quantities. The energy accumulated before peak point was low, and the energy released slowly. The specimenDs failure form was plastic and splitting. The impact energy index was low, and the smaller size specimen had weak bump- prone. The bigger size specimen口s compressive strength was big, and the acoustic emission concentrated around the failure point. The energy accum ulated before peak point was high, and the energy released rapidly. The specimenDs failure form was brittle and shearing. The impact energy index was high, and the b igger size specimen had strong bump- prone. A modified coefficient of the impact energy index in different diameters specimens was obtained, and the influence of the size effect on bump- prone testing result was decreased.

国家重点基础研究发展计划(973计划)资助项目(2012CB723104)；山东科技大学研究生科技创新基金资助项目(YC130202)；