防波堤和码头一体的双圆筒沉箱结构设计

Design of double cylindrical caisson structure integrating breakwater and wharf

针对兼具作业和防浪功能于一体的直立式双圆筒沉箱结构设计,提出船舶作业期间平均越浪量≤0.1 L∕(s·m)和风暴期间(100 a一遇)越浪量≤50 L∕(s·m)的高程控制标准。研究双圆筒采用混凝土薄板和厚板2种连接方式,并对其受力特性、计算模型、内力情况进行介绍。总结直立堤护底设计的推荐计算方法,发现CEM图表法与3D物模试验一致,OCDI法计算结果偏大,国标查图法计算块体稳定质量偏小。研究海侧挡浪墙设置在圆沉箱中部并设置反弧角的结构方案,提出的EurOtop法适用性广且结果贴近试验值;提出预制工字块封堵沉箱间填料并采用厚板连接堤头4个沉箱成整体的堤头保护方法;通过开展2D、3D模型试验验证了结构方案的可行性。研究成果可为类似设计提供参考。

This paper discusses the design of a vertical double cylindrical caisson structure that combines both operation and prevention functions.It proposes the elevation design standards during ship operations that the average overtopping is less than 0.1 L(s·m)and the overtopping is less than 50 L(s·m)during storms(once in a hundred years).The paper studies two kinds of connection modes of double cylinders using concrete thin plates and thick plates,and introduced their stress characteristics,calculation models,and internal forces.It summarizes the recommended calculation methods for the design of vertical embankment bottom protection,and it is found that the CEM chart method result is consistent with the 3D physical model test,the OCDI method has a larger calculation result,and the national standard mapping method has a smaller calculation of block stability weight.Furthermore,it studies the structural scheme of setting the sea side wave wall in the middle of a circular caisson with a reverse arc angle,and proposes that the EurOtop method has wide applicability and the results are close to the experimental values.Then,a method for protecting the embankment head is proposed by sealing the filling between the caissons with prefabricated I-blocks and connecting the four caissons at the embankment head with thick plates as a whole.The feasibility of the structural scheme has been verified through conducting 2D and 3D model experiments.The research results can provide reference for similar designs.