海洋环境混凝土功能组分优化设计与性能研究

针对海洋环境高性能铁路桥混凝土的耐久性和水化放热问题,通过轴心抗压、电通量、水化热等试验,对级配矿物外加剂与迁移型阻锈剂复合作用的高性能混凝土进行了研究.结果表明:掺入级配矿物外加剂、阻锈剂等功能组分后,通过配合比优化设计,混凝土试件28 d强度比基准组有所提高,钢筋表面的电化学性能得到进一步提升.同时,抗氯离子渗透性能比基准混凝土最大降低了39％,胶凝材料浆体水化热值比基准组降低了37％.当辅助胶凝材料粉煤灰和矿粉掺入量提高时,混凝土力学性能、抗氯离子性能得到进一步改善,水化热中的峰值会降低.复合矿物外加剂的掺量达到22％左右时,混凝土设计的综合性能达到较佳状态.掺入级配矿物外加剂和阻锈剂可以使电通量显著下降,并对混凝土耐久性的提升和水化热的控制具有协同作用.

Optimal Design and Performance of Concrete with Function Component in Marine Environment

This study aimed to the problem of durability and hydration of high performance concrete .In this paper , axial compression , electric flux , and thermal of concrete were tested , and high performance concrete which incorporated inhibitor and mineral admixture with different gradation were studied .The results showed that: With optimization design , 28 d strength of concrete specimens has increased by incorporation of mineral admixtures and migrating inhibitor , and the electrochemical property of the steel bar were with the further promoted .Meanwhile , Resistance to chloride ion penetration of concrete is 39％lower than reference concrete and hydration heat of cementious material decreased by 37％than reference sample .While increasing incorporation of fly ash and mineral powder , performance of resistance to chloride ions and strength of concrete improved , and peak of hydration heat was also reduced .When mineral admixture content reached 22％, it is possible to achieve the best performance of concrete .The electric flux dropped significantly while mineral admixtures and migrating corrosion inhibitor were incorporated , and mineral admixtures and inhibitor have synergistic effect on durability of concrete and control of hydration heat .