介绍半圆形防波堤和导堤结构在天津港和长江口深水航道治理工程中的设计应用情况，并对作用在半圆形防波堤上的波浪力计算方法研究以及半圆形防波堤的构造等发展概况作了论述。

The design and application of semi-circular breakwaters and estuary jetties at Tianjin Port and in the Deep Water Channel Improvement Project of Yangtze River Estuary are introduced in the present paper. The study of wave forces acting on semi-circular breakwater as well as the development of the structure of semicircular breakwater are also discussed.