石粉含量、含气量对 C50机制砂海工混凝土性能的影响

摘要

According to the rules of making use of local materials,granite manufactured-sand were used to prepare the C50 marine concrete to meet the pier construction of the highway and railway combined bridge over the Pingtan Strait.In this pa-per,several proportions of C50 manufactured-sand marine concrete for pier shafts were designed with different content of mi-cro-fines (5%,7%,10%)and different content of gas (2.5%,4.5%,6%),and the influence of micro-fines content and gas content on the workability,strength,the ability to resist chloride ion penetration as well as resistance to sulfate attack were discussed and then the best values of micro-fines content and gas content for preparing the marine concrete were achieved.Re-sults showed that the marine concrete that meets the requirement of durability design can be prepared by using granite manufac-tured-sand,and the best value of micro-fines content is 7%,the best value of gas content is 4.5% for the concrete mixture.%依据就地取材原则，本文采用花岗岩机制砂配制满足平潭海峡公铁两用大桥墩身施工的 C50海工混凝土。通过设计不同石粉含量（5％、7％、10％）及不同含气量（2．5％、4．5％、6％）的 C50机制砂海工混凝土，研究了石粉含量以及含气量对机制砂海工混凝土的工作性能、强度、抗氯离子渗透性能及抗硫酸盐侵蚀性能的影响，得出了配制海工混凝土时石粉含量及含气量的最佳值，试验表明：采用花岗岩机制砂可以配制出满足耐久性设计要求的机制砂海工混凝土，机制砂最佳石粉含量为7％，混凝土拌和物最佳含气量为4．5％。