Composite Modification Method of Recycled Coarse Aggregate Based on MMA Impregnation-Polymerization
FAN Yuhui
WANG Penghui
TAI Wusheng
XU Ping
LI Yan
Abstract：To solve the problem of the poor performance and high discreteness of recycled coarse aggregate concrete(RAC),a composite modification method combining cement paste pretreatment with methyl methacrylate monomer(MMA)impregnation-polymerization was investigated.The effects of the water-cement ratio,along with the polymerization temperature,time,and environment of MMA,on the performance of MMA composite-modified recycled coarse aggregate(RCA)were investigated.The results demonstrate that optimal modification is achieved with a 0.5 water-cement ratio,24 h MMA impregnation and 24 h polymerization at 70℃in a sealed environment.After MMA composite modification,there are 70.3%reduction in water absorption,41.9%decrease in crushing index,and 83.1%reduction in porosity of the RCA.The most probable pore diameter decreases from 62.50 nm to 5.93 nm,with total harmful and multi-harmful pore content reduces by 74.9%.Compared with conventional RAC,the 28 d cube compressive strength of modified recycled coarse aggregate concrete increases by 5.9%,9.5%,and 12.7%respectively,while the axial compressive strength improves by 4.1%,9.1%,and 14.1%respectively.The mechanical properties of RAC are significantly enhanced following MMA composite modification RCA.
Keywords：recycled coarse aggregateMMA composite modificationrecycled coarse aggregate concretemechanical property
Publication Date：2025-10-30
Online Publishing Date：2025-11-10(First online date of this platform, not the publication date of the document)
Pages：7( 1021-1027 )