ULTIMATE STRENGTH EXPERIMENT OF DIAPHRAGM IN FLAT STEEL BOX GIRDER FOR A LONG SPAN CABLE-STAYED BRIDGES

摘要

Su-tong Bridge over Yangtse River in China is a cable stayed bridge with a center span length of 1088m and its deck is an aerodynamic flat steel box. A specimen of scale 1∶3.0 was designed to simulate a segment of the box girder to investigate the ultimate strength and failure mechanism of the diaphragm under crane load on the deck. Experimental results indicated that 8 supports is better than 4 supports for a large traveling crane on deck and the ultimate strength of the diaphragm is governed by elastic buckling for such slender diaphragm as Su-tong Bridge.