论文部分内容阅读
埋入源激发波场分析对岩土工程勘探非常重要。基于模态叠加法给出均匀半无限体中埋入球形膨胀点源激发波场位移表达式,由此研究瑞利波可激性及其传播特性,分析埋入源下瑞利波可激性机制,并通过有限元模拟验证分析方法有效性。结果显示:在均匀半无限体中瑞利波可激性受源埋深与波长比影响,比值越小,瑞利波可激程度越高;当比值大于1时,瑞利波不易激发。与自由状态下以平面波阵面传播的简正瑞利波相比,半无限体中埋入源激发瑞利波速度随传播距离变化,传播具有空间特性,距中心轴线越近,竖直向质点振动相速度越小,当距离大于一个波长时,激发瑞利波传播特性趋于简正瑞利波。
Buried source excitation wavefield analysis is very important for geotechnical exploration. Based on the modal superposition method, the displacement expression of the excitation field in the spherical expansive point buried in a uniform and semi-infinite body is given. The excitability and propagation characteristics of the Rayleigh wave are studied. The Rayleigh wave excitability Mechanism, and verify the validity of the method through finite element simulation. The results show that the Rayleigh wave excitability is affected by the buried depth and the wavelength ratio in a uniform and semi-infinite body. The smaller the ratio, the higher the Rayleigh wave excitability; when the ratio is greater than 1, the Rayleigh wave is not easy to be excited. Compared with the Jian-Liang Rayleigh waves propagating in a plane wavefront in a free state, the excitation-excited Rayleigh wave velocity in a semi-infinite body varies with the propagation distance. The propagation has the spatial characteristic. The closer to the central axis, the vertical to the particle vibrational phase The smaller the speed, when the distance is greater than one wavelength, the excitation Rayleigh wave propagation characteristics tend to Jane Rayleigh waves.