神东矿区覆岩岩石纵波波速与力学性质的关系研究

Discussion on the Relationship Among Longitudinal Wave Velocity and Mechanical Properties of Overlying Rock in Shendong Mining Area

岩石(体)的抗压强度、纵波波速是评价岩体强度、稳定性、围岩分级的重要指标。以神东矿区大柳塔煤矿覆岩为研究对象,首先采用超声波测试岩石波速,然后进行单轴压缩试验和间接拉伸试验,获得岩石的单轴抗压强度、抗拉强度、弹性模量、纵波波速和泊松比等物理力学参数,最后对不同种类岩石的波速与力学参数之间的关系进行探讨。研究结果表明:不同岩石的抗压强度、抗拉强度和弹性模量与岩石纵波波速之间的线性相关性有不同程度的差异。其中,砂质泥岩抗压强度与纵波波速之间呈现出明显的离散性,抗拉强度、弹性模量与纵波波速之间均具有一定的线性关系;粉砂岩抗压强度与纵波波速之间存在一定的相关性,抗拉强度、弹性模量与纵波波速之间线性相关性明显;细粒砂岩抗压强度与纵波波速之间离散性小,有较好的相关性,抗拉强度与纵波波速之间相关性较明显,弹性模量与纵波波速之间有着很明显的线性相关性。

The compressive strength and longitudinal wave velocity of rock(body)are very important indexes to evaluate the strength,stability and surrounding rock classification of rock mass.Taking the overlying rock of Daliuta coal mine in Shendong mining area as the research object,firstly,the ultrasonic wave was used to test the wave velocity of rock,and then the uniaxial compression test and indirect tensile test were carried out to obtain the physical and mechanical parameters of rock,such as uniaxial compressive strength,tensile strength,elastic modulus,wave velocity and poisson ratio.Finally,the relationship between longitudinal wave velocity and mechanical parameters of different kinds of rock was discussed.The results show that the linear correlation between the compressive strength,tensile strength and elastic modulus of different rocks with the longitudinal wave velocity of rocks has different degrees of difference.Among them,the compressive strength and longitudinal wave velocity of sandy mudstone show obvious discreteness,and the tensile strength and elastic modulusa have certain linear relationships with longitudinal wave velocity.There is a certain correlation between compressive strength and longitudinal wave velocity of siltstone,and the tensile strength and elastic modulus have an obvious linear correlation with longitudinal wave velocity.The discreteness between compressive strength and longitudinal wave velocity of fine-grained sandstone is small,and there is a good correlation.The correlation between tensile strength and longitudinal wave velocity is obvious,and there is a significant linear correlation between elastic modulus and longitudinal wave velocity.