静定问题。萨尔玛96基于条分法发展了一种方法，在此法中，产生极限平衡所要求的临界地震加速度是确定的。这种分析方法在分析中假定了条块间垂直作用力的分配。同样的，满足所有的平衡条件，破坏面可以是任何形状。静安全系数是土的抗剪强度必须减小，以致于临界加速度为零时的系数。计算机的使用对于贝尔法和萨尔玛法来说，是必不可少的。所有的解答必须要检查，以确保它们在物理学上是可以接受的。
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