斜长角闪岩累积损伤特性的围压效应研究

摘要

Dynamic mechanical performance experiments were carried out for amphibolites specimens under the cyclical impact loadings by using the split Hopkinson pressure bar equipment with confining pressure device. Based on the calculation of energy during the experiments and analysis of stress-strain curves, the relationship among the accumulative total of special energy absorbency, confining pressure, and damage of amphibolites under the cyclical impact loadings were analyzed. It is demonstrated that the effect of special energy absorption value on lower confining pressure level is more than that on the incident wave energy, and there exist relationships among special energy absorbency, incident energy and confining pressure. When the confining pressure increased gradually, the increase of damage became slow along with the accumulative special energy absorbency, i.e. , the higher confining pressure, the more energy needed for amphibolites to reach the same damage level. The formulas were putted forward for the damage, accumulative special energy absorbency and confining pressure.%利用带围压装置的SHPB设备对不同围压等级下斜长角闪岩在冲击荷载循环作用下动态力学性能进行试验研究，通过对试验过程的能量计算和不同循环作用次数下试件应力-应变曲线的分析，研究斜长角闪岩在冲击荷载循环作用下的累积比能量吸收值与入射能量，损伤度与围压等参量之间的关系。研究结果表明，当入射波能量相同时，斜长角闪岩的比能量吸收值随围压的增加而减小，且斜长角闪岩的比能量吸收值与围压和入射波能量具有良好的规律性。当围压逐渐增大时，斜长角闪岩损伤度的增加随累积比能量吸收值增加的趋势变缓，即围压越高，试件达到相同损伤度所需耗散的能量越多。得到损伤度D与累积比能量吸收值和围压之间的关系表达式。