无限饱水孔隙弹性空间中由运动源所产生的位移场
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摘要
基于Ｂｉｏｔ的饱和孔隙弹性介质的运动方程和利用复变函数方法，本文研究了无限饱水孔隙弹性空间中由常速运动源所产生的位移场。考虑了两种类型源：ａ．沿无限空间水平轴运动的斜向集中力源；ｂ．运动双力偶源。关于力源的运动速度，考虑了４种情形：ａ．力源的运动速度Ｕ小于饱水孔隙弹性介质的三种体波速度一亚音速情形；ｂ．速度Ｕ小于介质的第一纵波过度和横波速度，但大于第二纵波速度─—弱跨音速情形；ｃ．速度Ｕ小于第一纵波速度，但大于横波速度和第二级波速度─—强跨音速情形；ｄ．速度Ｕ大于介质的所有三种体波速度─—超音速情形。结果表明，在跨音达和超音速情形里，解呈现出与力源相联系的平面冲击波特征，位移出现了相应的跳跃。
Based on Biot's basic motion equations for the fluid saturated porous elastic medium and by using the method of complex function,the displacement field due to moving source with umiform veloicy U in an infinite porous elastic saturated space is studied in present paper,Two types of sources are considered:a. An oblioue concentrated pulse force moving along the horizontal axis of the infinite space,b. The moving couples of forces.There are four cases for the moving velocity of force source: a.The velocity U is less than all three types of body wave velocities of the fluid saturated porcus elastic medium, the subsonic case. b. The velocity U is less than the first dilatational wave velocity and the rotational wave velocity of the medium, but greater than the second dilate-tional wave velocity,the weak transonic case. c.The velocity U is less than the first dilatational wave velocitty, but greater than the velocities of the second dilatational and the rotational waves, the strong transonic case. d.The velocity U is greater than all three types of body wave velocities, the supersonic case. The results show that in the transonic and supersonic cases, the solutions represent the character of plane chock waves attacted to the load and associated with a jump in the displacement.
Based on Biot's basic motion equations for the fluid saturated porous elastic medium and by using the method of complex function,the displacement field due to moving source with umiform veloicy U in an infinite porous elastic saturated space is studied in present paper,Two types of sources are considered:a. An oblioue concentrated pulse force moving along the horizontal axis of the infinite space,b. The moving couples of forces.There are four cases for the moving velocity of force source: a.The velocity U is less than all three types of body wave velocities of the fluid saturated porcus elastic medium, the subsonic case. b. The velocity U is less than the first dilatational wave velocity and the rotational wave velocity of the medium, but greater than the second dilate-tional wave velocity,the weak transonic case. c.The velocity U is less than the first dilatational wave velocitty, but greater than the velocities of the second dilatational and the rotational waves, the strong transonic case. d.The velocity U is greater than all three types of body wave velocities, the supersonic case. The results show that in the transonic and supersonic cases, the solutions represent the character of plane chock waves attacted to the load and associated with a jump in the displacement.
引文
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