Wave velocity as a nondestructive test is widely used in various fields such as mining, civil, rock mechanics and rock engineering, and dynamic elastic properties of rocks are also determined by wave velocity. Rock mass contains discontinuities with different orientation angles, numbers of sets and frequencies and the impacts of such discontinuity properties on the wave velocity have not yet been systematically investigated. In this study, 20 groups of jointed cylindrical specimens with a wide range of discontinuity orientation angles (0°, 30°, 45°, 60° and 90°), numbers of sets and frequencies were prepared, and their P-wave velocities were measured. P-wave velocity (V_P) significantly increased with increasing orientation angle (θ) and decreasing the discontinuity frequency (F). Several relations were applied to analyze the results. Finally, a new empirical relation was developed to predict V_P as a function of θ angle using two parameters of P-wave velocity perpendicular to the discontinuity plane (V_P0°) and P-wave velocity along the discontinuity direction (V_P90°) or anisotropy degree (ε = (V_P90° − V_P0°)/V_P0°) with a good correlation of determination (R² = 0.933), low RMSE (RMSE = 200.0 m/s) and low CV (CV = 6.7%). A good correlation between V_P and F was also achieved for the test results. The intact rock elements in the complex nature of a rock mass are surrounded by discontinuities like a three dimensional puzzle. Treatment of such a rock mass system using cement grouting is an attractive method to improve its quality for various purposes. All 20 groups of jointed cylindrical specimens were grouted by cement. Wave velocities of the grouted specimens were measured after 2 months. V_P significantly increased after grouting for all models of jointed specimens, as wave velocity of jointed specimens improved and approached to the wave velocity of the intact rock for most cases. The discontinuity orientation of the specimens had no significant effect on the wave velocities after grouting. But the results showed that V_P and V_S increased little with increasing orientation angle for jointed specimens consisting only of one set of discontinuity. After grouting the jointed specimens, orientation angle and frequency of discontinuities had also similar effects on the dynamic Young's modulus (E), Poisson's ratio (ν), shear modulus (μ), bulk modulus (K) and Lamé’s constant (λ). These results also showed that the dynamic elastic properties of jointed specimens significantly improved using cement grouting.

波速作为一种无损检测被广泛应用于采矿、土木、岩石力学和岩石工程等各个领域，岩石的动态弹性特性也是由波速决定的。岩体包含具有不同取向角、组数和频率的不连续性，并且尚未系统地研究此类不连续性特性对波速的影响。本研究制备了 20 组具有大范围不连续取向角（0°、30°、45°、60°和 90°）、组数和频率的连接圆柱试样，其纵波速度分别为测量。P 波速度 ( V _P ) 随着方向角 ( θ ) 的增加而显着增加) 并降低不连续频率 ( F )。应用几个关系来分析结果。最后，使用垂直于不连续面的 P 波速度 ( V _P0° ) 和沿不连续方向的 P 波速度 ( V _P90° )两个参数，开发了一种新的经验关系来预测V _P作为θ角的函数或各向异性度 ( ε  = ( V _P90°  −  V _P0° )/ V _P0° ) 具有良好的测定相关性 ( R ² = 0.933)、低 RMSE (RMSE = 200.0 m/s) 和低 CV (CV = 6.7%)。测试结果也实现了V _P和F之间的良好相关性。岩体复杂性质中完整的岩石元素被不连续性包围，就像一个三维拼图。使用水泥灌浆处理这种岩体系统是一种有吸引力的方法，可以为各种目的提高其质量。20组接缝圆柱试件均采用水泥灌浆。2 个月后测量灌浆试样的波速。副_总裁所有模型的节理试样灌浆后显着增加，因为节理试样的波速提高并在大多数情况下接近完整岩石的波速。灌浆后试件的不连续性方向对波速没有显着影响。但结果表明，对于仅由一组不连续点组成的连接试样，随着取向角的增加，V _P和V _S几乎没有增加。接缝试件灌浆后，取向角和不连续性频率对动态杨氏模量（E）、泊松比（ν）、剪切模量（μ）、体积模量（K) 和拉梅常数 ( λ )。这些结果还表明，使用水泥灌浆显着改善了接缝试件的动态弹性性能。