In order to study the influence of dunn bass on the mechanical deformation characteristics of the ore body,the full-y refined industrial paraffin was chosen as the simulation material of dunn bass,and made proportioning with cement and mineral powder to prepare the test specimens. The failure characteristics of the ore rock with dunn bass were clarified through the combined representation of mechanical deformation characteristics for dunn bass test specimens during the loading process by the surface wall crack propagation,microscopic imaging,surface wall strain value change,overall loading compression de-formation,magnetic induction intensity change and infrared temperature measurement. A numerical simulation method of dunn bass was put forward,and the change of safety coefficient,the maximum principal stress and the strain at different mo-nitoring points for ore rock with different dunn bass contents were monitored. The results showed that more cracks appeared on the surface wall of test specimens with dunn bass during the loading process,with the short cracks as primary,and the distribution region was wide. The change of longitudinal strain on surface wall was more stable,while the transverse strain presented a stepped change. The infrared temperature measurement had no constant change amplitude,with a fluctuant change of ups and downs. The change of magnetic induction intensity had the characteristics of ascending and descending type,descending and steady type,and descending and ascending type. The numerical simulation results showed that the ex-istence of dunn bass weakened the overall strength of ore rock,which was consistent with the similar simulation results. Dif-ferent dunn bass strength had different influence on the overall stability of ore rock. When the overall stability of test speci-men related to the physical properties of dunn bass,and the dunn bass strength was about 50% of the ore strength,they con-tacted with each other closely,and the existence of dunn bass and its content had little influence. If the dunn bass strength was only 2% of the ore strength,the corresponding measurement points fluctuated greatly. If the integrity of specimen was bad,there were many microscopic empty space,and the strain value change of the corresponding measurement points around the empty space fluctuated greatly.%为研究夹石对矿体力学变形特性的影响,选用全精炼的工业石蜡作为夹石模拟材料,并与水泥和矿粉进行配比制样.通过表壁裂纹扩展、微观成像、表壁应变值变化、整体加载压缩变形、磁感应强度变化、红外温度测量共同表征夹石试样在加载过程中的力学变形特征,厘清夹石矿岩的破坏特点.同时提出了一种数值模拟夹石的方法,进行不同夹石含量矿岩的安全系数、最大主应力及不同监测点处应变值的变化监测.试验结果表明:存在夹石的试样在加载过程中表壁出现较多裂纹条数,且以短裂纹为主,分布区域较广;表壁纵向应变变化较平稳,而横向应变存在阶梯型变化;红外温度测量并无恒定的变化幅度,存在升降的起伏变化;磁感应强度值变化存在上升下降型、下降平稳型、下降上升型的变化特点.数值模拟结果表明:夹石的存在弱化了矿岩的整体强度,这与相似模拟结果具有一致性.同时不同的夹石强度对矿岩的整体稳定性影响不一样.当试样的整体稳定性与夹石的物理性质有关,夹石强度是矿石强度50%左右时,彼此接触严丝合缝,夹石存在及含量的多少产生的影响不大;如果夹石强度只是矿石强度的2%时,相应的测点起伏变化较大;如果试样完整性不好,存在较多微观空区,空区附近的相应测点的应变值变化起伏较大.
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