The seawall fault tree is the system in series, and the key to the fault tree is the solution to conditional probability P (B/A).

• 海塘失效概率树为串联概率树，而条件概率尸(B/A)解求是串联概率树要解决的关键问题，为此提出了假定条件概率近似符合正态分布，然后做积分变换推求条件概率的思路；