再生粗骨料对混凝土收缩性能影响的试验研究  

Experimental research on the influence of recycled coarse aggregate on the shrinkage of concrete

作　　者：王新杰[1] 徐巍[1] 封金财[1] 朱平华[1] 

机构地区：[1]常州大学土木工程系,江苏常州213164

出　　处：《混凝土》2015年第8期59-62,共4页Concrete

基　　金：国家自然科学基金项目(51278073);江苏省六大人才高峰项目;常州大学自然科学基金项目(ZMF1002122;ZMF1002124);江苏省产学研联合创新资金--前瞻性联合研究项目(BY2013024-17)

摘　　要：为了探讨混凝土抗压强度和收缩与再生粗骨料取代率之间的关系,研究了再生粗骨料取代率为30%、40%、50%和70%混凝土的28 d立方体抗压强度和自收缩、干燥收缩的变化趋势,并建立了自收缩和干燥收缩与取代率和龄期之间的函数关系。结果表明:改变再生粗骨料的取代率,混凝土抗压强度呈三次抛物线变化,在取代率为50%时混凝土抗压强度取得最大值;再生混凝土的自收缩、总收缩和干燥收缩与普通混凝土变化趋势相同,在龄期3 d前发展较快,龄期7 d后相对趋于平缓;再生混凝土的收缩变形随再生粗骨料取代率的增加而逐渐增大,且在龄期28 d时再生混凝土各个取代率的干燥收缩增长幅度都大于自收缩。For the purpose of exploring the influence of recycled coarse aggregate replacement ration on compressive strength and shrinkage of concrete, the cube compressive strength at the age of 28 days, autogenous shrinkage and drying shrinkage of concrete with the recycled coarse aggregate replacement rate of 30% ,40% ,50%and 70%were researched. And the functional relationship between the autogenous shrinkage, drying shrinkage and the recycled coarse aggregate replacement rate, age of concrete was established. The results show that the compressive strength reached to the largest when the replacement ratio of recycled coarse aggregate is 50%, and the rela- tionship between cubic compressive strength and replacement ratio is found to be cubical parabola. The variation trend of autogenous shrinkage and total shrinkage and drying shrinkage of recycled concrete were similar to the natural concrete. The shrinkage developed rapidly before the age of 3 d, and it growth flattens relatively after the age of 7 d. The shrinkage of recycle concrete was increasing with the content of recycled coarse aggregate increased. And at the age of 28 d, the increase amount of drying shrinkage for each substitution rate was larger than autogenous shrinkage.

关 键 词：再生混凝土 再生粗骨料 取代率 混凝土的收缩 立方体抗压强度 

分 类 号：TU528.041[建筑科学—建筑技术科学]