沥青铺装层厚度对连续刚构桥主梁温度梯度应力的影响

通过对连续刚构桥梁常用的2种沥青混凝土铺装层结构分析得知,沥青铺装层厚度是影响梯度温度效应的最重要因素.对连续刚构桥主梁梯度温度应力计算公式进行分析,得到梯度温度应力不随梁高发生显著变化的初步原因,并依托重庆渝宜高速公路2座桥梁的分析结果予以证实.根据实例分析和比较发现,沥青厚度变化导致的竖向日照温差对梁顶应力影响较大...

Effect of Asphalt Bridge Deck Pavement Depth on Beam Temperature Gradient Stress of Continuous Rigid Frame Bridges

Aiming at 2 common bridge deck pavements of continuous rigid frame bridges,it is discussed that the depth of asphalt bridge deck pavement is the main factor influencing temperature gradient stress.The calculation function for temperature gradient stress of continuous rigid frame bridges is analyzed,and the preliminary causes that the temperature gradient stress will not change obviously along with the beam height are gained.The forward results are verified by the analysis results from 2 bridges in the highway from Chongqing to Yibin.According to the analysis and comparison in case study,beam upper side stress will change obviously with vertical temperature gradients caused by the asphalt pavement depth,however,vertical temperature gradients have little effect on the beam lower side stress.The beam upper side stress caused by temperature gradient stress will reach more than 50% of dead load stress,which obviously exceeds the upper side stress of truck loading.The beam upper side stress caused by the change of 1 cm asphalt bridge deck pavement will reach 30%-40% upper side stress caused by truck loading.The stress condition of beam can be adjusted by the reasonable alteration of asphalt bridge deck pavement depth.