RESEARCH ON SUN LIGHT TEMPERATURE FIELD AND THERMAL DIFFERENCE EFFECT OF LONG SPAN BOX GIRDER BRIDGE WITH CORRUGATED STEEL WEBS

At present, no solar temperature gradient for the box girder with corrugated steel webs has been found in any codes for design of highway bridges and culverts of China, and the relevant research about the sun light temperature gradient is limited. With this regard, a large span continuous box girder bridge with corrugated steel webs in Hong Kong-Zhuhai-Macao Bridge was taken as an example in the paper, and three-day observation of the sun light temperature field of box girder section with corrugated steel webs was carried out, and then the distribution law of the sun light temperature field was studied. The mathematical models of vertical and lateral temperature gradient of box girders with corrugated steel webs were proposed, and the values of thermal parameters were discussed. According to the data of field test and calculation of finite element software, the values of temperature difference in different temperature gradient models were calculated and the temperature difference effect was comparatively analyzed. The research results show that the temperature field distribution of box girders with corrugated steel webs is significantly different with that of the traditional box girder. The temperature gradient model can be defined by a piecewise function composed of exponential function and linear function. The vertical and lateral temperature difference values of box girders with corrugated steel webs, which are calculated by proposed models, matched well with the measured results. Due to the temperature effect, biggish transveral stress is generated in the lower edge of the top slab around the axis, which should be paid more attention in the design. This temperature gradient pattern can be used as important reference in calculating the temperature loads of the same type bridges in different climatic conditions.