水泥稳定再生骨料混合料的疲劳寿命分析

Fatigue Life of Cement Stabilized Recycled Aggregate Mixtures

为了研究再生骨料掺量及龄期对水泥稳定再生骨料路面基层疲劳寿命的影响,对掺有0%、30%、60%、100%的再生骨料混合料试件在60 d和90 d龄期下进行弯拉疲劳试验,然后采用Weibull函数,对混合料的疲劳试验结果进行分析处理及线性拟合,建立不同再生骨料掺量、龄期与应力水平的关系。试验结果表明:在应力水平一致的情况下,一旦开始掺加由废旧路面基层破碎加工而成的再生骨料,其疲劳寿命显著降低,但当掺量在30%以后,其疲劳寿命又开始逐步稳定甚至逐渐提高,直至掺量为100%时再生骨料混合料疲劳寿命只是略低于未掺再生骨料混合料试件;在再生骨料掺量一致的情况下,当龄期增长时,混合料试件的疲劳寿命也逐渐增大。

Recycled aggregate content and age are two important factors affecting fatigue life of cement stabilized recycled aggregate pavement base.In the test,the dosage of 0%,30%,60%,100%,the age of 60d and 90d are chosen to carry out the bending and tensile fatigue test.Then,the Weibull function was used to analyze and process the fatigue test results of the mixture,and then the test data was linearly fitted,the relationship between different recycled aggregate content,age and stress level was established.The relationship was established between different recycled aggregate content,age and stress level.The results showed that under the same stress level,the fatigue life of the cement stabilized recycled aggregate mixtures is higher than that of the cement stabilized recycled aggregate base mixture,and the base mixture mixed with recycled aggregate has a rapid decrease in fatigue resistance at 30%.However,as the content of recycled aggregate continues to increase,its fatigue life begins to increase.The fatigue life of 100%recycled aggregate concrete is just slightly below that of the road base without recycled aggregate.Under the same content of recycled aggregate,the fatigue life of recycled aggregate mixture increases with the increase of age.