柔性基层沥青路面动力响应试槽试验

根据室内试槽柔性基层沥青路面结构的重复加载试验,总结了路用电阻应变片的选择依据和黏贴工艺,对比分析了压路机压实方式对应变片存活率的影响;利用惠斯登电桥电路测试了柔性基层沥青路面的动力响应,并与数值计算进行对比。研究表明:路用电阻应变片栅长应大于80 mm,并与集料的最大公称粒径相关;电阻应变片在压路机静压的方式下有较理想的存活率,而在强振作用下却极难存活;在移动荷载作用下沥青面层底部横向应变交替出现拉、压应变,其最大值比层状弹性体系模型计算值小。

Test on Dynamic Response of Flexible Base Asphalt Pavement

According to repeated load test of flexible base asphalt pavement,the structure is built in the indoor pit.The principle of choosing resistance strain gauges and the surface-sticking process of gauge was summarized;the survival rate of strain gauge based on the comparison of road roller’s compaction mode strong vibration or static pressure was discussed.The data of time-history curves was collected through the Wheatstone Bridge with the numerical calculation comparative study.The detection results show: the gate length of resistance strain gauge should not be less than 80mm,which is related to nominal maximum size of aggregate.Gauges’ survival rate is affected by different compaction model,which is much lower under the strong vibration model.Also the response of strain in layer bottom under the dynamic load of moving vehicle is more complex than that in static situation.However,the current pavement structure design method needs transforming from static model to dynamic load model.