就地热再生沥青混合料优化研究

Study on Optimum Design of Locally Thermal Regeneration Asphalt Mixture

为明确忻州境内国道209线路面改造工程原沥青路面混合料的设计配合比,通过分析原路面沥青混合料级配情况和添加不同掺量再生剂沥青混合料的试验结果,确定了复拌沥青混合料的再生剂含量、热沥青含量、新添加混合料含量及油石比。研究结果表明:通过抽提筛分试验可分析原路面沥青混合料级配情况,并确定再生剂用量与回收沥青用量;通过对不同再生剂含量的沥青进行三大指标和体积指标试验,得到较优的再生剂含量;按照不同的油石比,将新混合料、再生剂、热沥青与原路面沥青混合料进行复拌,通过马歇尔试验得出沥青路面改造最佳油石比;通过对复拌沥青混合料试件进行高温稳定性、马歇尔及冻融劈裂检验,其动稳定度DS为5322次·mm^(-1),残留稳定度为91.5,冻融劈裂强度比为85.7%。

In order to determine the design mix proportion of the original asphalt pavement mixture in Xinzhou National G209 surface reconstruction project,this study analyzed the grade of asphalt mixture of original pavement and the test results of adding different regenerant,the content of regenerant,the content of hot asphalt,the content of newly added mixture and the ratio of oil to stone were determined.The results show that,the gradation of original pavement asphalt mixture can be analyzed through extraction and screening test,the amount of regenerant and recovered asphalt was determined,three index tests and volume index tests were carried out on asphalt with different regenerant content,the effect of regenerant on improving asphalt compatibility was obtained,better regenerant content can be obtained;depending on the ratio of oil to stone,the new mixture,regenerant,hot asphalt and the original pavement asphalt mixture are remixed,through Marshall test,the best oil stone ratio of asphalt pavement reconstruction in this project is obtained,the high temperature stability,residual Marshall and freeze-thaw splitting of the remixed asphalt mixture were tested,all the indicators meet the requirements of the standard,the dynamic stability DS=5322 times·mm-1,the residual stability is 91.5,and the freeze-thaw splitting strength ratio is 85.7%.