充填节理岩石累积损伤动力压缩特性试验研究

Experimental study on dynamic compression characteristics of rock with filled joints after cumulative damage

充填节理的动态力学特性及其对应力波传播规律的影响是岩体工程响应和安全性评价的重要依据。由于现有对充填节理岩石累积损伤及动力强度弱化特性研究较少,研究对人工充填节理岩石试样展开了系列试验,分析了岩样累积冲击作用下的损伤演化规律及其对动态力学性能的影响。首先,利用简易落锤冲击装置对岩样进行多次预冲击试验,通过波速变化分析了充填节理岩样的累积损伤变化规律。在此基础上,对不同次数预冲击作用后的充填节理岩石试样进行了SHPB动态冲击破坏试验。通过试验结果,分别从岩样的强度变形特征、波传播特性以及能量耗散等方面分析了累积预冲击作用对充填节理岩石动态力学性能的影响。

The dynamic mechanical behaviour of filled rock joints and its influence on stress wave propagation are important bases for dynamic response analysis and safety evaluation of rock mass engineering.In view of the lack of research on the cumulative damage and the strength weakening of filled joints by dynamic loading disturbance,series of tests are carried out on the artificial filled jointed rock samples to study the damage evolution rule under the cumulative impacts and its influences on the dynamic mechanical properties in this present paper.A simply equipped drop hammer impact device is used to carry out multiple pre-impact tests on the jointed rock samples,then the cumulative damage law is analyzed through the change of the wave velocity.On this basis,the dynamic impact tests of SHPB are carried out on filled jointed rock samples after different numbers of pre-impact.Based on the test results,the influence of cumulative damage on the dynamic mechanical properties of the filled jointed rock is analyzed from the aspects of strength deformation characteristics,wave propagation characteristics and energy dissipation.