桥梁清水自密实混凝土的工作性能及早期抗裂性能研究

Study on workability and early crack resistance of bridge fair-faced self-compacting concrete

结合桥梁清水自密实混凝土工程特点及要求,从原材料筛选、胶材用量及掺合料比例调整、骨料类型及粒径控制、最佳砂率选取等方面进行配合比设计,选取最佳清水处理工艺,探讨自密实工作性能影响因素,对比试件表观性能指标,开展耐久性试验。结果表明:制备的桥梁清水自密实混凝土倒坍时间1.8 s,V漏时间12 s,间隙通过性好,自密实性能优良,含气量1.8%,无明显色差,无裂缝,表面气泡极少,清水表观性能优秀,耐久性好。

This project combines the characteristics and requirements of bridge fair-faced self-compacting concrete project,and designs mix proportion from raw material selection,mortar dosage and admixture proportion adjustment,aggregate type and particle size control,optimal sand ratio selection and so on.It chooses the best fair-faced treatment technology,explores the influencing factors of self-compacting performance,compares the apparent performance index of specimens,and carries out durability test.The results show that the prepared bridge self-compacting concrete with fair-faced has good collapsing time of 1.8 s,V leakage time of 12 s,good clearance passage,excellent self-compacting performance,1.8%air content,no obvious color difference,no cracks,very few surface bubbles,excellent fair-faced apparent performance and good durability.