CAJ | 학술논문

在显式有限元方法结合黏弹性人工边界的时域波动方法的基础上，建立了地震波垂直输入时的一种简化输入方法。将近场有限元模型沿高度方向进行分层，将地震动的入射运动转化为作用于人工边界底面及分层后每层侧面上的均布力，以实现地震动的输入。与以等效节点力的方式实现的地震动输入相比，施加均布力的方式简化了地震波输入的前处理工作，且又能保证与等效节点力方式相同的精度。自由场数值算例表明：当该方法中的分层高度与波动有限元网格离散要求的最大尺寸相等时，该方法与等效节点力方法具有相同的精度；当局部区域按网格离散要求的最大尺寸进行分层而在其它区域放大分层高度时，局部区域上的近场波动响应仍可保证具有相当高的精度。另外，某隧道结构地震响应算例的计算结果同样说明了该方法的有效性。
재현식유한원방법결합점탄성인공변계적시역파동방법적기출상，건립료지진파수직수입시적일충간화수입방법。장근장유한원모형연고도방향진행분층，장지진동적입사운동전화위작용우인공변계저면급분층후매층측면상적균포력，이실현지진동적수입。여이등효절점력적방식실현적지진동수입상비，시가균포력적방식간화료지진파수입적전처리공작，차우능보증여등효절점력방식상동적정도。자유장수치산례표명：당해방법중적분층고도여파동유한원망격리산요구적최대척촌상등시，해방법여등효절점력방법구유상동적정도；당국부구역안망격리산요구적최대척촌진행분층이재기타구역방대분층고도시，국부구역상적근장파동향응잉가보증구유상당고적정도。령외，모수도결구지진향응산례적계산결과동양설명료해방법적유효성。
On the basis of the time-domain wave method combined with the explicit finite element method and the viscous-elastic artificial boundary condition,a simplified seismic wave input method for near-field wave analysis was proposed.With this approach,the near-field model was stratified in the height direction,and then the seismic motion was converted into stresses acted on the viscous-elastic artificial boundary to realize seismic wave input.Compared with the equivalent node force input method,the new method simplified the antecedent processing with an acceptable accuracy. The numerical results obtained from a free ground model indicated that when the stratified size equals the maximum size of the element mesh in dynamical analysis,the accuracy of the simplified method is the same as that of the equivalent node method;when the local parts of the near-field model were stratified with the maximum element mesn size of dynamical analysis while the other parts were stratified with a lager size,the dynamic responses of the local parts have a higher accuracy.Moreover,the dynamic response computation results of a rock tunnel demonstrated the effectiveness of the proposed simplified approach.