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To solve the Xinjiang region is more widespread salinization of concrete subjected to sulfate attack problems, from full use of fly ash in Xinjiang local resources to start Ⅱ grade to grade Ⅱ fly ash as admixture of concrete and mortar specimens through test, observation, water-cement ratio 0.40,0.35,0.30, Ⅱ grade fly ash content of 30%, 40% and 60% of the concrete strength properties and resistance to sulfate attack were analyzed; each group on trial specimens were observed and electron microscopic morphology microscopic analysis. The study found: (1) For the doped Ⅱ grade fly ash concrete, the main factors affecting the intensity of the water-cement ratio, fly ash, age. With the lower water-cement ratio, age increases the compressive strength of concrete, especially when the water-cement ratio decreased by 0.1, the compressive strength increases more apparent. (2) the use of low water-cement ratio, select the appropriate superplasticizer, prepared by high-performance concrete technical grade Ⅱ High Volume Fly Ash Concrete, although its early strength is low, but the rapid development of the late strength, indicating under the conditions of low water-cement ratio, Ⅱ grade fly ash aggregate fill the role of micro-and post-hydration effect on the compressive strength of the contribution is still more significant. The use of controlled water-cement ratio and Ⅱ grade fly ash approach can be formulated to meet the requirements of the different general engineering strength grade concrete. (3) doped Ⅱ grade fly ash specimens not resist coefficient is higher than ordinary specimens with fly ash, especially Ⅱ grade of 60% fly ash specimens, which was significantly higher than the resist coefficient Other test pieces resist coefficient Description Ⅱ grade fly ash concrete can be significantly improved when the larger anti-acid corrosion performance. (4) In the short-instar (3 days) curing conditions, the use of low water-cement ratio, when Ⅱ grade fly ash content of 60%, the corrosion resistance of high concentration solution (sulfate ion concentration of 8000mg / L, 20250mg / L) erosion effect is remarkable. Therefore, when completed is expected soon after concrete pouring subjected to high concentrations of sulfate attack and difficult to avoid, we recommend the use of low water-cement ratio, high volume fly ash to prepare Ⅱ grade performance concrete, can be economically, effectively improve concrete resistance to erosion. (5) the use of low water-cement ratio mortar specimens prepared after a high concentration of sulfate attack after soaking solution, the occurrence of erosion and damage the performance of the specific form of the specimen surface gradually loose, peeling, and there are a lot of loose layer of plaster in the folder. The interior of the specimen did not find a lot of ettringite filling expansion phenomenon.
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