铜黄高速公路C50高性能混凝土耐久性研究

Study on Durability of C50 High Performance Concrete in the Highway from Tongchuan to Huangling

铜川—黄陵高速公路沿线环境干燥、温差大等特点对混凝土耐久性提出很高要求,基于此,结合当地丰富的工业废弃物(粉煤灰和矿粉),制备性能优良的C50混凝土,研究矿物掺合料对混凝土耐久性的影响,利用压汞法分析其微观结构。研究结果表明,掺加矿物掺合料可显著提高混凝土抗氯离子渗透性、抗硫酸盐侵蚀性及抗冻性,延长初裂时间50%以上;掺加矿物掺合料可降低混凝土孔隙率、优化孔隙结构。

The characteristics of dryness and large temperature difference along the highway from Tongchuan to Huangling put forward high requirements on the durability of concrete. Based on this,combined with local rich industrial waste( fly ash and mineral powder) can prepare C50 concrete with excellent properties. The effect of mineral admixture on the durability of concrete was studied,and its microstructure was analyzed by mercury intrusion method. The results show that the addition of mineral admixture can significantly improve the chloride ion permeability,sulfate attack resistance and frost resistance of concrete,and prolong the initial cracking time by more than 50%. Adding mineral admixture can reduce the porosity of concrete and optimize pore structure.