泉州后渚大桥温度场测试与温度内力分析

Measurements of thermal gradients and their effects on the static behavior of the Houzhu bridge in Quanzhou

泉州后渚大桥主桥为5跨预应力混凝土连续刚构桥,通过对施工阶段温度场的监测,得到混凝土箱梁高度方向与箱内外温度场的分布规律.以修正后的有限元模型为基础,考虑整体升温或降温,计算了连续刚构桥梁的温度内力和变形.结果表明:与恒载内力相比,温度变化产生的内力不可忽视;升温使边墩的弯矩减小,轴力和剪力加大,而中间桥墩的内力变化正好与边墩相反.

The Houzhu bridge is a pretressed concrete continuous rigid- framed bridge with five spans. This paper presents concrete temperature data through the depth of the box girder. These data were collected continuously during the construction over half a year period. The maximum-recorded thermal differentials are reported and analyzed. Based on the calibrated finite element （FE） model, the thermal effects on the static behavior of the bridge were calculated through considering the temperature increase or decrease. The results reveal that the inner-forces caused by temperature change cannot be neglected, while comparing the inner-force caused by self-weight. When the temperature increases, the moment in the sidedpier of the bridge will be reduced, but the axial force and shear force will be added. The change of innerforces in the middle-piers is just the opposite while comparing with that of the sided-piers.