应力波作用下花岗岩损伤演化的试验研究

发布时间：2018-04-12 06:56

本文选题：SHPB + 应力波　；参考：《中国矿业大学（北京）》2014年博士论文

【摘要】：以工程实践中常见的花岗岩为研究对象，采用SHPB装置对其进行多次冲击试验研究，选择400mm、600mm、800mm、1000mm四种不同长度子弹对花岗岩试件进行冲击，从应变波形、破损模式、实测本构关系曲线等方面研究了应力波参数与岩石破损特性之间的关系。试验结果得出花岗岩的动态响应参量演化过程大都服从幂律分布的形式，当损伤D小于0.2时，，各动态参量服从较一致的幂律分布，表现为以波幅为变量的指数函数形式；损伤D大于0.2时，波长对岩石的动态参量影响显著增大，并发现花岗岩损伤D为0.73时，即将进入失效状态。充分考虑花岗岩的自身状态和应力波特性，建立了岩石损伤演化模型=f(ε,,λ)，认为波长λ对损伤演化的影响是通过岩石的应变率体现的。并通过石灰岩和砂岩的系列冲击试验验证了此损伤关系和演化模型的适用性。
[Abstract]:Taking the granite commonly used in engineering practice as the research object, using SHPB device to carry out multiple impact tests, four kinds of bullets of different length (400mm / 600mm / 800mm / 1000mm) were selected to impact the granite specimen, according to the strain waveform and damage mode,The relationship between stress wave parameters and rock damage characteristics is studied in terms of measured constitutive curves.The experimental results show that the evolution process of dynamic response parameters of granite is mostly in the form of power law distribution. When the damage D is less than 0.2, the dynamic parameters of granite follow the same power law distribution, which is the exponential function with the amplitude of wave as the variable.When the damage D is greater than 0.2, the influence of wavelength on the dynamic parameters of rock increases significantly, and it is found that when the damage D of granite is 0.73, it will enter into the failure state.Considering the state of granite and the characteristics of stress wave, the damage evolution model of rock is established. It is considered that the influence of wavelength 位 on damage evolution is reflected by the strain rate of rock.The damage relationship and the applicability of the evolutionary model are verified by a series of impact tests of limestone and sandstone.
【学位授予单位】：中国矿业大学（北京）
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TU45

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