含瓦斯煤岩三维蠕变特性及蠕变模型研究

RESEARCH ON TRIAXIAL CREEP PROPERTIES AND CREEP MODEL OF COAL CONTAINING GAS

研究含瓦斯煤岩的三维蠕变特性是理解煤与瓦斯突出孕育过程中瓦斯和煤岩相互作用关系的重要方面,而目前含瓦斯煤岩三维蠕变特性的研究很少,因此需要进一步深入研究含瓦斯煤岩的三维蠕变特性。基于这一认识,采用自行研制的含瓦斯煤岩蠕变实验装置,对取自重庆松藻煤矿的煤样进行含瓦斯煤岩三轴蠕变试验。研究结果表明,含瓦斯煤岩的三轴蠕变特性具有明显的蠕变规律。在含瓦斯煤岩三维蠕变特性的基础上,通过改进西原模型的参数,建立改进的西原模型,由此推导出含瓦斯煤岩三维应力状态下的蠕变方程,并通过拟合得到蠕变方程中的各个参数。利用含瓦斯煤岩的蠕变试验结果,对三维蠕变方程进行验证,发现理论结果与试验数据有着很好的一致性。研究结果表明,由改进的西原模型推导出的含瓦斯煤岩三维蠕变方程能真实反映含瓦斯煤岩的蠕变特性。

The research on triaxial creep properties of coal containing gas is the important aspect of understanding the interactional relationship between gas and coal in the course of outburst. At present,there are few reports on triaxial creep properties of coal containing gas,so it is necessary to further research triaxial creep properties of coal containing gas deeply. By using self-developed creep experimental apparatus,a series of triaxial creep experiments on coal containing gas have been performed with coal samples which were taken from Songzao Coal Mine in Chongqing. The experimental results indicate that the triaxial creep properties of coal containing gas have a good regularity. In terms of the triaxial creep properties of coal containing gas,a modified Nishihara model under triaxial stress condition has been built by improving the model parameters of Nishihara. Moreover,the creep equations under triaxial stress condition have been deduced from the modified Nishihara model,and each parameter of the equations has been achieved by fitting the experiment results. The prediction by the model is in agreement with the experimental data is experimentally validated. The research shows that the triaxial creep equations from modified Nishihara model can reflect effectually the creep properties of coal containing gas.