Modifying Recycled Aggregate Concrete by Aggregate Surface Treatment Using Sulphaluminate Cement
Recycled aggregate (RA) was surface treated by a strengthening slurry prepared with sulphoaluminate cement (SAC).The modification effects of such surface treatment on properties of both RA and recycled aggregate concrete (RAC) were experimentally studied, meanwhile the modification mechanism was revealed based on property changes of interfacial transition zones (ITZs) contained in RAC.Test results show that the SAC slurry can significantly improve the properties of both RA and RAC, on the macro scale.The density and strength of RA was enhanced and the water absorption was reduced by the SAC slurry.By using the treated RA, RACs performance including workability, mechanical properties, i.e., compressive strength and density degree, and durability, i.e., resistance to chloride ingress, was also improved.Microhardness test results demonstrated that after RAs surface treatment, ITZ1s and ITZ3s which formed between the old coarse aggregate and the new mortar, and between the old and new cement mortars, were enhanced.ITZ2s which originally existed inside RA particles between the old coarse aggregate and the old adhering cement mortar were not enhanced.The old cement mortar was surface strengthened.Considering the cost efficiency as well as the easy operation, surface treating RA by using the SAC slurry has a good prospect on the wide application in real projects.
Recycled aggregate concrete Modification Surface Treatment Sulphaluminate cement
H.Liu H.R.Zhang S.L.Su
College of Civil Engineering, Fuzhou University, Fuzhou, China
国际会议
福州
英文
141-149
2018-11-04（万方平台首次上网日期，不代表论文的发表时间）