水泥级配再生碎石的冻融破坏研究  

Frost-thaw damage of cement stabilized graded recycled aggregate

作　　者：牛景轶[1] 杜丰音 高嵩[1] NIU Jingyi;DU Fengyin;GAO Song(College of Civil Engineering,Qingdao University of Technology,Qingdao 266033,China)

机构地区：[1]青岛理工大学土木工程学院,山东青岛266033

出　　处：《混凝土》2018年第8期149-152,共4页Concrete

基　　金：国家自然科学基金项目(51378269);铁道部科研计划项目(2014G004-F);山东省高等学校人文社会科学研究项目(J14WB57)

摘　　要：水泥级配再生碎石的强度、空隙率以及在低温下的稳定性直接关系到高速公路的安全性。采用逐级填充方法制备了最大振动压实密度为2.07 g/cm^3,最小空隙率为26.44%的级配再生碎石。研究了不同水泥掺量、不同粉煤灰取代率水泥级配再生碎石的强度、空隙率及在冻融和低温下的质量损失及强度损伤。试验结果表明:水泥级配再生碎石的强度,抗冻融、冻胀破坏能力随水泥掺量增加而增加,但随粉煤灰取代率增加而下降。掺加5%~7%水泥的级配再生碎石能抵抗15~20次快速冻融破坏,以及9次冻胀破坏。水泥级配碎石空隙率和渗透性随水泥掺量以及粉煤灰取代率增加而降低,水泥掺量降低增加了级配再生碎石的宏观缺陷。The safety of highway was influenced by compressive strength,voidage and low temperature resistance capacity of cement stabilized graded recycled aggregate.The well-grade recycled aggregate with maximum compactness density of 2.07 g/cm^3 and minimum viodage of 26.44%was prepared by grading fill test.And then the compressive strength,voidage of cement stabilized graded recycled aggregate with different cement content and fly ash replacement rate were tested,and there mass loss and strength reduction under freeze-thaw and low temperature were also studied.The experimental results indicated that the compressive strength,freeze-thaw and low temperature resistance capacity of cement stabilized graded recycled aggregate promoted with cement content,but decreased with fly ash replacement rate.The cement stabilized graded recycled aggregate with 5%~7%cement content could keep good performance after 15~20 cycles of frost-thaw and 9 times of frost heave.Additionally,the voidage and permeability of cement stabilized graded recycled aggregate reduced with cement content and fly ash replacement rate,and the macro-defects would increase with decreasing cement content.

关 键 词：再生碎石 冻融 空隙率 强度 

分 类 号：TU528.062[建筑科学—建筑技术科学]