节点文献
静载和动力扰动联合作用下砂岩时滞性破坏试验研究
Experimental study on time-delayed failure of sandstone under the combined action of static load and dynamic disturbance
【摘要】 地下工程施工过程中岩爆的发生与岩石时滞性破坏特性密切相关,而且开挖爆破、机械钻凿等动力扰动直接影响岩爆的形成过程。基于此,特开展不同幅值和频率动力扰动作用下的砂岩时滞性破坏试验,分析动力扰动作用对岩石时滞性破坏的影响规律及机制。研究表明:(1)不同幅值(8%~24%)和频率(0.2~1.0 Hz)扰动作用下岩样破坏孕育时间显著缩短,相较无扰动作用岩样破坏孕育时间缩短了39.49%~98.21%;随着扰动荷载频率和幅值增大,岩样加速变形阶段持续时间占比逐渐减小,破坏突发性增强。(2)随着扰动荷载幅值和频率增加,岩样破坏时的片状剥落现象逐渐减弱,裂纹产生的随机性明显增强,说明动力扰动荷载改变了岩样的时滞性破坏形式和程度。(3)动力扰动作用下岩样损伤变量随扰动时间呈倒S型增长规律,建立了考虑静载和动力扰动作用的岩石时滞性累积损伤模型。(4)静力加载阶段岩样积聚大量弹性能并造成初始损伤,动力扰动作用加剧了损伤演化进程并不断诱发新的损伤,扰动作用幅值和频率增加均会加速岩石损伤进程,使得试样承载能力下降,进而诱发岩爆。相关研究成果可为深部岩体工程动力触发时滞性岩爆分析解释提供较好的参考。
【Abstract】 The occurrence of rock bursts during underground engineering construction is closely related to the time-delay failure characteristics of rocks. Dynamic disturbances such as excavation blasting and mechanical drilling directly impact the formation process of rock bursts. Time-delay failure tests on sandstone under dynamic disturbances of varying amplitudes and frequencies were conducted to analyze their impact and mechanism on rock failure delays. Research findings indicate: 1) Under different amplitudes(8%–24%) and frequencies(0.2–1.0 Hz) of disturbances, the incubation time for rock sample failure significantly shortens, by 39.49%–98.21% compared to undisturbed conditions. With increasing frequency and amplitude of the disturbance load, the proportion of the accelerated deformation stage duration in the rock sample gradually decreases, leading to an increase in the sudden failure. 2) Increasing amplitude and frequency of disturbance loads weaken the flaky peeling phenomenon during rock sample failure and increase the randomness of crack generation,altering the time-delay failure form and degree of rock samples. 3) The damage variable of rock samples under dynamic disturbance exhibits an inverted S-shaped growth pattern over time. A time-delay cumulative damage model for rocks considering static loads and dynamic disturbances has been developed. 4) During the static loading stage, the rock sample accumulates elastic energy and incurs initial damage. The dynamic disturbance intensifies the damage evolution process, leading to continuous induction of new damage. Increasing amplitude and frequency of the disturbance accelerates rock damage, causing a reduction in sample bearing capacity and ultimately triggering rock burst. These research findings can provide valuable references for analyzing and interpreting time-delayed rock bursts induced by dynamic forces in deep rock mass engineering.
【Key words】 dynamic disturbance; time-delayed; rockburst; amplitude; frequency; energy;
- 【文献出处】 岩土力学 ,Rock and Soil Mechanics , 编辑部邮箱 ,2025年01期
- 【分类号】TU45
- 【下载频次】59