非均布荷载作用下煤岩力学强度特性试验研究

发布时间：2018-04-01 08:03

本文选题：非均布荷载　切入点：力学强度　出处：《岩土力学》2017年03期

【摘要】：考虑不同初始垂向应力、不同初始水平应力及不同应力转移速度条件,借助于自主研发的采动应力试验系统,研究了非均布荷载作用下煤岩体的力学强度特性。研究结果表明:煤岩外部损伤残余块体对煤岩内部力学承载能力具有强化作用,当初始垂向应力、初始水平应力、应力转移速度一定时,煤岩内部力学承载能力近似为煤岩外部力学承载能力的2倍;伴随初始垂向应力的增加,煤岩整体后期力学承载能力不断降低,且处于不同初始垂向应力范围,煤岩内、外部后期力学强度递减特征不同,当处于较小初始垂向应力范围时,煤岩外部后期力学强度递减量大于煤岩内部,当处于较大初始垂向应力范围时,煤岩外部后期力学强度递减量小于煤岩内部;初始水平应力越大,煤岩体的力学承载能力越高,且无论较小还是较大初始水平应力范围,煤岩内部后期力学强度增量总大于煤岩外部;伴随应力转移速度的增加,煤岩峰值强度不断升高,应力转移速度对煤岩内部区域力学性质的影响相对较大。
[Abstract]:Considering different initial vertical stresses, different initial horizontal stresses and different stress transfer rates, the mechanical strength characteristics of coal and rock mass under non-uniform load are studied by means of the self-developed mining stress test system.The results show that the residual block of external damage of coal and rock can strengthen the mechanical bearing capacity of coal and rock. When the initial vertical stress, the initial horizontal stress and the stress transfer rate are fixed,With the increase of initial vertical stress, the mechanical bearing capacity of coal and rock decreases continuously in the later stage, and it is in different initial vertical stress range, in coal and rock, the internal mechanical bearing capacity of coal and rock is about 2 times of that of coal and rock, and the mechanical bearing capacity of coal and rock decreases continuously in the later stage with the increase of initial vertical stress.In the later stage of coal and rock, the decline of mechanical strength is larger than that of coal and rock, and when the initial vertical stress range is large, the decline of mechanical strength is different.The larger the initial horizontal stress, the higher the mechanical bearing capacity of coal and rock mass, and the smaller or larger the initial horizontal stress range is.The increment of mechanical strength in the later stage of coal and rock is always larger than that outside the coal and rock, and with the increase of stress transfer velocity, the peak strength of coal and rock increases continuously, and the stress transfer velocity has a relatively large influence on the mechanical properties of coal and rock.
【作者单位】：山东科技大学矿山灾害预防控制省部共建国家重点试验室培育基地;阿尔托大学;澳大利亚联邦科学院能源部;
【基金】：国家自然科学基金(No.51304126) 国家重点研发计划(No.2016YFC0600708-3) 国家重点试验室开放基金(No.SKLGDUEK1520) 霍英东青年教师基金(No.141046) 中国博士后基金(No.2013M541918) 2015年度山东省高等学校科技计划(No.J15LH04)~~
【分类号】：TD315

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