很多教材中提到,对底部为模量较大的岩石的模型进行动力分析时,设置图中的这种边界,请问flac3d6.0中实现这种边界是这样写吗?我目前遇到的问题是z向输入的地震动加速度,在地表响应正常,但是如果输入x或y向的加速度,地表响应会在一秒钟趋向零,不知道是否是边界条件设置有问题,请大家解答!

```model dynamic active on
zone face apply-remove range position-x -10 10 position-y -10 10 position-z 0 0
zone face apply-remove range position-x -10 10 position-y -10 10 position-z 0 0
zone face apply-remove range position-x -10 10 position-z 0 25 position-y -10 -10
zone face apply-remove range position-x -10 10 position-z 0 25 position-y 10 10
zone face apply-remove range position-y -10 10 position-z 0 25 position-x -10 -10
zone face apply-remove range position-y -10 10 position-z 0 25 position-x 10 10
zone face apply quiet range position-y -10 10 position-z 0 25 position-x -10 -10
zone face apply quiet range position-y -10 10 position-z 0 25 position-x 10 10
zone face apply quiet range position-x -10 10 position-z 0 25 position-y -10 -10
zone face apply quiet range position-x -10 10 position-z 0 25 position-y 10 10
table '1' import 'D:/qiuxing/cs2/ei.txt'
zone face apply acceleration-z 9.8 table '1' range position-x -10 10 position-y -10 10 position-z 0 0
zone dynamic free-field on