摘要
冲击地压发生的“时-空”特征难以预测,严重制约了煤炭资源的安全、高效产出。从日月引潮力对采场围岩循环加卸载的作用机制出发,统计2001~2021年典型冲击地压事故的时空分布特征,利用理论分析和数据统计厘清了日月引潮力与冲击地压的内在联系,采用CASRock细胞自动机分析软件,研究2种日月引潮力时程作用模式对冲击地压类型的触发机制,并提出基于时间窗口效应的岩石循环加卸载应力路径优化方法。研究结果表明:(1)日月引潮力与冲击地压发生都具有明显的地域差异性,在日月引潮力的循环加卸载作用下,冲击地压发生的时间主要集中在2月和9月及每月的农历初一、十五左右。(2)日月引潮力的2种时程作用模式下的累积声,发射数量、等效塑性剪应变(Epstn)、岩石破裂度(RFD)均大于常规三轴加载,表明在日月引潮力的作用下,煤岩体更易发生应力跌落,由弹性向塑性转化,并释放更多的弹性能,更易诱发冲击地压。(3)从冲击力源出发,日月引潮力的2种时程作用模式分别容易诱发重力型冲击地压和构造应力型冲击地压。(4)揭示了日月引潮力对于冲击地压的触发机制实际上是日月引潮力对于采场围岩重复循环加卸载的作用结果。并在分析常见的循环加卸载应力路径基础上,结合矿井工作制度,将每日的生产期间划分为加载阶段,检修期间划分为卸载阶段,提出基于时间效应优化的采场围岩应力路径。上述研究结果可以更好地应用于岩石力学实验,为真实反映煤岩试件在采动应力路径作用下的冲击破坏规律提供新的方法。
The“time-space”characteristics of rock bursts are difficult to predict,which severely restricts the safe and efficient output of coal resources. Starting from the mechanism of the sun-moon tidal force on the cyclic loading and unloading of the surrounding rock,the temporal and spatial distribution characteristics of typical rock burst accidents from 2001 to 2021 were calculated. The internal relationship between the sun-moon tidal force and rock burst has been clarified using theoretical analysis and data statistics. The trigger mechanism of the two time-history action modes of sun-moon tidal force on rock burst has been studied through cellular automata analysis software(CASRock). A method for optimizing rock cyclic loading and unloading stress paths based on the time window effect was proposed. The research results show that:(1) both the sun-moon tidal force and the occurrence of rock bursts have obvious regional differences. Under the cyclic loading and unloading of the sun-moon tidal force, the occurrence time of rock bursts was mainly concentrated in February and September and around the first and fifteenth days of the lunar calendar.(2) The cumulative acoustic emission quantity,equivalent plastic shear strain(Epstn),and rock fracture degree(RFD) under the two time-history action modes of the sun-moon tidal force are all greater than conventional triaxial loading. It shows that under the action of sun and moon tidal forces,coal and rock masses are more prone to stress fall,transform from elasticity to plasticity and release more elastic energy,and it is easier to induce rock bursts.(3) Starting from the source of impact force,the two time-history action modes of sun-moon tidal force are easy to induce gravity-type rock burst and structural stress-type rock burst respectively.(4) It is revealed that the trigger mechanism of the sun-moon tidal force on rock burst is actually the result of the repeated cyclic loading and unloading of the surrounding rock. Based on the analysis of common cyclic loading and unloading stress paths,combined with the mine work system,the production period was divided into the loading phase,and the maintenance period was divided into the unloading phase. The stress path of the surrounding rock based on time effect optimization was proposed. The above research results can be better applied to rock mechanics experiments,and provide a new method for real reaction to the rock burst failure law of coal and rock samples under the action of the mining stress path.
作者
崔峰
张廷辉
CUI Feng;ZHANG Tinghui(College of Energy Engineering,Xi'an University of Science and Technology,Xi'an,Shaanxi 110054,China;Key Laboratory of Western Mines and Hazard Prevention of Ministry of Education,Xi'an University of Science and Technology,Xi'an,Shaanxi 710054,China;Key Laboratory of Coal Resources Exploration and Comprehensive Utilization,Ministry of Natural Resources,Xi'an,Shaanxi 710021 China)
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2021年第S02期3107-3117,共11页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金资助项目(51874231)
陕西省创新能力支撑计划(2020KJXX-006)
陕西省自然科学基础研究计划企业联合基金项目(2019JLZ-04)。