粉煤灰沙基灰砖碳化养护力学性能与长期承载耐久性研究OACHSSCD

To improve the utilization rate of aeolian sand in arid regions,aeolian sand from the Kumtag Desert and ClassⅡ fly ash were used as aggregates,while quicklime and gypsum served as cementitious materials.Fly ash-aeolian sand lime bricks were prepared under high-pressure CO2 curing.The slurry concentration was fixed at 79%,with a sand-to-ash ratio of 13∶6 and an ash-to-binder ratio of 14∶4.The effects of CO2 pressure(0.2～1.0 MPa)and curing age(3～28 d)on compressive strength were investigated,and creep simulation was conducted based on the optimal parameters(0.6 MPa,14 d).The results indicate that the compressive strength increases rapidly at early ages and then gradually stabilizes;at 0.6 MPa,the 28 d compressive strength reaches 9.8 MPa.The bricks are suitable for filling in shallow and moderately shallow goafs,providing both solid waste resource utilization and CO2 sequestration.