圆弧面防波堤波浪力初步研究

圆弧面防波堤是在半圆形防波堤基础上开发的一种新型防波堤。首先通过与半圆形防波堤相同条件下的波浪试验,检验圆弧面防波堤的稳定性,并利用数值波浪水槽对圆弧面防波堤的水力特性进行初步研究,探求造成圆弧面防波堤与半圆形防波堤波浪力差别的主要原因。通过圆弧面防波堤与半圆形防波堤波浪力的对比试验,提出了圆弧面防波堤波浪力的简化计算方法,以半圆堤正向水平波浪力乘以一修正系数,在堤顶淹没情况下修正系数可取1.3,在堤顶出水情况下修正系数可取1.1。

Preliminary research on wave forces on quarter circular breakwater

The quarter circular breakwater is a new type breakwater developed on the basis of the semi-circular breakwater.This type of breakwater is composed of a quarter circular front wall,a horizontal base slab and a vertical rear wall,the width of which is about one half of that of the semi-circular breakwater,suitable to be used on relatively firm soil foundation.The engineering quantity of the rubble mound foundation of this new type of breakwater can be reduced.The stability of the quarter circular breakwater is examined by wave model tests with the same condition as the semi-circular breakwater option.The numerical wave flume is used to study the hydraulic characteristics of the quarter circular breakwater preliminarily in order to find out the main reason for the difference of wave forces on the quarter circular breakwater and on the semi-circular one.Based on comparison tests of wave forces acting on these two types of breakwaters,a simplified calculation method of wave forces on the quarter circular breakwater is proposed: the horizontal wave force can be expressed by applying a modification coefficient to that for the semi-circular breakwater.The modification coefficient can be taken as 1.3 for submerged condition or 1.1 for the breakwater with a freeboard.