海滩养护过程和工程技术

Beach Nourishment Process and Engineering Technology

海滩养护是根据设计方案,向海滩大量抛沙,或者同时辅以硬工程,使受蚀海滩增宽和稳足的工程,是抵御海岸侵袭灾害的最佳措施。上世纪末发达国家已普遍开展,我国目前尚属起步,但近年发展迅速。该工程分调查,重建和修补3个阶段,三者相互补充和制约。重建前必须充分调查目标岸段,以为设计养护方案提供依据;重建阶段应注重抛沙位置、沙成分、抛沙量和沙源选择等工序;重建后应进行多年的剖面监测和再抛沙的修补。在那些浪大,沙少和岩礁裸露的侵蚀岸段,应辅以丁坝或岸外潜坝等硬工程加以抵浪,维持所填沙的稳定。

Beach nourishment is an engineering used to widen and stabilize an eroding beach by filling abundant sand with or without supporting structures. It provides a best protection to coast erosion and has been applied in the coast protection widely in the developed countries since the end of the last century, and has been developing rapidly in recent years. Beach nourishment includes investigation, restoration and replenishment stages, which are mutual complementing and interacting. It＇s necessary to survey the coastal environment sufficiently to make a design before restoration, whereafter, to consider filling locations, components, quantity and sources of sand, and to emphasize the beach profile monitoring continuously and sand filling regularly during the replenishment. In the eroding coast with strong wave, absent sand and bare rock, groyne or jetty and offshore submerged groin engineering are needed to support this nourishment against the waves in order to maintain the filled sand stability.