PS测井在公路隧道勘察中的应用

THE APPLICATION OF PS-WAVE LOGGING IN TUNNEL EXPLORATION OF HIGHWAY

介绍了单孔法PS测井的原理极其相应的数据处理方法。通过获取地震波经过不同深度的岩土的直达波旅行时便可求得纵横波波速,进而通过弹性波理论基础即可根据纵横波速度计算出泊松比、剪切模量、扬氏模量、体积模量、拉梅常数、风化系数、岩体完整性系数、岩体波速等岩土动力学参数。这些参数可对隧道围岩等级做出评定,为隧道设计提供必要的依据。同时,由PS测井所得到的土层及强、中、弱风化层的纵横波速还可对面波和折射波勘探中风化层位的划分起标定作用。文中结合某一具体公路隧道勘察的应用效果,展现了该方法获取岩土动力学参数的有效、快捷的特点及其在隧道勘察中的应用前景。

The principles and data processing means of single well PS-wave logging method are described on the paper. The velocities of P- wave and S- wave may be obtained by measuring the travel time of first break from seismic wave field propagated through rock and soil at different depths. Furthermore, some kinetic parameters of rock and soil, such as Poisson＇s ratio, shear modulus, Young＇s modulus, bulk modulus, Lame＇s constant, weathering factor and integrity factor of rock mass etc. , may be figured out accordingto the velocities of P-wave and S-wave based on elastic theory. All these parameters are called on to evaluate grade of surrounding rock and supply necessary warranties for tunnel design. Meanwhile, the velocities of P-wave and S-wave gained by PS-wave logging from soil and severe, middling and mild weathering strata may take very important role in weathering demarcation for Rayleigh wave and refraction wave explorations. Finally, according to application effects of the method in a concrete tunnel exploration, both the traits of effectiveness and shortcut to obtain kinetic parameters of soil-rock and its potential application prospects are also exhibited.