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西北地区冻结立井爆破对早期高强砼井壁损伤研究

The Damage Study of Early-age High Strength Concrete Shaft Lining Subjected to Blasting Load in Northwest Freezing Shaft

【作者】 王二成

【导师】 单仁亮;

【作者基本信息】 中国矿业大学(北京) , 结构工程, 2014, 博士

【摘要】 针对我国西北部地区煤炭资源的储藏特点和采用冻结爆破建井中遇到的问题,本文在理论分析的基础上,采用现场试验、数值模拟和模型试验相结合的方法对西部冻结立井中处于低温环境下的早龄期高强混凝土井壁在经受爆破荷载作用下的损伤情况进行了详细的研究与分析。结合现场情况配制了高强混凝土,通过抗压强度试验和超声波测试技术,得到了混凝土在标准养护和低温环境下的强度增长规律和超声波变化规律。通过快速循环加卸载试验,得到了混凝土在准动态荷载作用下的损伤情况和超声波波速变化情况及它们的相关性。对低温环境下养护且处于低温下的早龄期高强混凝土试件进行了霍普金森压杆试验研究,得出了早龄期高强混凝土在低温情况下受单次和多次重复冲击作用下的动态力学性能。通过现场试验、数值模拟和模型试验,得出了爆破荷载作用下高强混凝土井壁的振动传播规律、井壁的变形和受力规律、损伤及变化规律。综合以上研究结果,对安全判据条件进行了分析。

【Abstract】 According to the store characteristic of coal resource in our northwest country and the problemencountered in excavating shaft with freezing method, and on the basis of theoretical analysis, thedamage of early-age high strength concrete shaft lining in low temperature environment subjected toblasting load when excavation in frozen shaft was researched and analysis in detail through situ test,numerical simulation and model test. High strength concrete was made and measured for thestrength growth law and ultrasonic variation law in standard curing and low temperature conditionaccording to situ environment with compression test and ultrasonic wave measure method. Thedamage and ultrasonic variation of concrete,and the correlation relationship between them wereanalyzed through quickly and repeatedly load and unload test. The dynamic mechanical property ofearly-age high strength concrete subject to one and twice impact load was gained from its SHPB testin standard curing and low temperature condition. Vibration propagation law,deformation and stresslaw,and damage variation law of high strength concrete shaft lining subjected to blasting load merecalculated out from situ test data,numerical model data and model test data. The safety criterion wasalso analyzed based on above research results.

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