Researches on stopover during migration of Anatidae birds were carried at Yellowriver wetland, freshwater lake areas in Yulin city and Hanjiang river in winter from 1998 to 2003.
1998-2003年冬季,作者相继在关中平原东部的黄河湿地、陕北榆林淡水湖泊区以及汉江流域对雁形目鸟类的迁徙状况进行了研究。
The design results of the bird-shape plates according to the new and old codes for design of concrete structure are compared respectively.
分别按新、旧混凝土设计规范对雁形板进行设计。
By means of static loading and destruction test on two 18 m span bird-shape plates before and after strengthening, the change of the bird-shape s bearing capacity is analyzed which is strengthened by external tendon.
通过两根 18m跨雁形板在用体外预应力筋加固前后的静载及破坏实验 ,分析研究了体外预应力加固雁形板后的承载力变化 ,并按比拟梁法对加固构件的承载力进行了计算。