Safety Assessment And Reliability Of Seawall In The East Zhejiang Under Powerful Typhoon

Seawall in the coastal area is an important social infrastructure. with a defensive action such as waves and tides, as a barrier to prevent the storm surge. Owing to complex geological conditions in Zhejiang coastal areas, leakage of seawall, insufficiency elevation, the cracking of structures and the scour of toe after years of running affect safety of seawall. Therefore, to carry out the safety evaluation and reliability analysis of seawall under the typhoon condition has important significance to coastal disaster prevention and reduction.This article summarizes the safety evaluation of seawall at home and abroad. Analysis the damage of seawall in east Zhejiang under the condition of the powerful typhoon, Evaluate the security and defense ability of typical seawall and analysis the reliability. The main contents are as follows:1、Based on the investigation of the basic situation of seawall in east Zhejiang and the historical data of typhoon, analysed the landing typhoon in Zhejiang province from1949to2005, expounds the login space characteristics and seasonal distribution of the typhoon in zhejiang province, Analyzed damage of seawall under the condition of typical powerful typhoon.2、According to the physical index and mechanics index, analyzed characteristics of seawall soft soil foundation in Zhoushan, Ningbo, Wenzhou, Taizhou, expounds safety factor of the seawall.3、Chosen typical seawall in Zhoushan, Ningbo, Wenzhou, Taizhou, inspect the safety of the structure, the evaluation of residual subsidence and body stability safety were carried out on seawall, calculat the reliability of waves overflow dam and body’s stability.4、Considering differences of the major coastal tide level station between different frequency characteristic value、differences between the waves and not allow the waves, Evaluate of defense of the standard seawall Once every100、50、20and10years.