1.Nanjing University of Aeronautics and Astronautics;2.Qinghai university;3.Qinghai Building Materials Research Institute
The National Basic Research Program of China (973 Program)
以西北地区高浓度盐碱环境为背景，研究了含潜在碱活性细骨料的大掺量矿物掺合料高性能混凝土（high performance concrete，HPC）在Na+-Cl--SO42-型卤水中的力学性能和损伤演变. 结果表明：卤水浸泡3650 d时HPC的相对动弹性模量大于90%，抗腐蚀系数大于1，膨胀率小于0.12%；较高的当量碱含量部分加剧了碱硅酸反应(ASR)；引气能够提高抗卤水腐蚀能力以及降低ASR膨胀. 采用大掺量矿物掺合料和潜在碱活性细骨料强度等级为C50的HPC，在Na+-Cl--SO42-型卤水中具有优良的长期耐久性.
The saline lake and saline soil areas in northwestern China are the strong saline-alkali environment due to the high concentration chloride and sulfate, which can easily cause corrosion and the alkali-silica reaction (ASR) in concrete. This paper presents an investigation on the mechanical properties and damage evolution of high performance concrete (HPC) with large amount of mineral admixtures and potential alkali active fine aggregate exposed Na+-Cl--SO42- brine environment. The results indicated that (1) the relative dynamic elastic modulus is greater than 90%, the compressive corrosion coefficient and flexural corrosion coefficient of HPC are greater than 1 and the expansion rate is less than 0.12%; (2)the higher equivalent alkali content partially aggravated the alkali-silica reaction (ASR) in HPC; (3)air entraining can improve the brine corrosion resistance of HPC and reduce the expansion by ASR. HPC of C50 with high content of mineral admixtures and potential alkali active fine aggregate has excellent long-term durability in Na+-Cl--SO42- saline lake brine.