Thermal Stress in Main Girder of Long-span Pre-stressed Concrete Cable-stayed Bridge

摘要

Based on the spatial finite element model of Huai'an Bridge, the widest long-span prestressed concrete cable-stayed bridge in China now, under the actions of the temperature gradient in design specification of JTG D60-2004 and rise of temperature equally on the top slab in specification of JTJ 021-89, the distribution patterns of the temperature stresses on the top slab, the bottom slab and the transverse diaphragm in the prestressed concrete main girder were investigated respectively. The results of analysis show that there are high principle tensile stresses on the bottom slab and the transverse diaphragm under the temperature loads, while under the temperature gradient pattern, there are higher principle tensile stresses on the bottom slab and the transverse diaphragm which will probably cause their crack. The results also show that the influence of the temperature stress in the main girder of the prestressed concrete cable-stayed bridge calculated by JTG D60-2004 is larger than that by JTJ 021-89, so the results calculated by JTG D60-2004 are inclined to be safer.