浙江典型海塘实时安全监测分析

海塘是浙江沿海及海岛抵御台风暴潮的第一道防线。针对海塘跨域大、台风期恶劣气候影响严重以及海塘外部影响对内部响应变化速度快的特点，提出了大范围、分布式、集中管理的远程实时动态海塘安全监测技术，并对钱塘江海宁盐仓段标准塘和浙东海塘舟山万丈塘进行实时监测。监测结果表明海塘内部渗压水位与潮位有较好的相关性，潮位涨落对海塘渗流影响由海塘外侧至内侧逐渐减弱;海塘内部水力坡降均小于允许坡降，海塘渗透稳定满足要求。在潮涌作用下，海塘将产生mm级水平变形，随着潮位涨落，海塘内部水平位移呈周期性变化;水平位移沿深度分布呈现上部大、下部小的特点。研究成果为海塘的日常维护和应急抢险提供技术支撑。

Analysis of Real-time Safety Monitoring for Typical Seawalls in Zhejiang Province

Seawall is the first barrier against typhoon storm surge for coastal areas and islands in Zhejiang Province.Cutting through broad areas,seawalls are severely affected by bad climate in typhoon period with rapid internal response to external influence.In view of this,a remote real-time dynamic monitoring technology for seawall safety is presented with features of large coverage,distributed monitoring and centralized management.The real-time monitoring technology was applied to the standard seawall at Yancang of Haining City in Qiantang River,as well as Wanzhang seawall of Zhoushan City in east Zhejiang.Monitoring results show that the inner water level of seawall obtained through seepage pressure gauge is well related to tide level,and the effect of tidal level fluctuation on seepage gradually weakens from the inside to the outside of seawall.The internal hydraulic gradient of seawall is within allowable value,guaranteeing seepage stability.Moreover,horizontal deformation at millimeter level would occur under the action of tide.With the tide level fluctuation,internal horizontal displacement of seawall changes cyclically.In particular,the horizontal displacement of the upper part of seawall is greater than that of the lower part.The real-time monitoring results provide technical support for routine maintenance and emergency treatment of the seawall.