(1. School of Civil Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China) (2. National and Provincial Joint Engineering Laboratory of Road & Bridge Disaster Prevention and Control, Lanzhou Jiaotong University, Lanzhou 730070, China)(3. Xi’an Railway Survey and Design Institute Co., Ltd., Xi’an 710054, China)(4. China Railway 21st Bureau Group Co., Ltd., Lanzhou 730070, China)
In order to further explain the mechanism of concrete deterioration by sulfate erosion, the resistance to sulfate erosion of concretes samples with different water-cement ratio and curing time under full immersion conditions and sulfate solution diffusion in concrete were studied. Cement concrete samples with water-cement ratio of 0.32, 0.35 and 0.38 were prepared. The evaluating indicators such as the mass, dynamic elastic modulus, compressive strength and sulfate ion content were analyzed. The results show that,under the condition of Na2SO4 solution full immersion, the resistance to sulfate attack increases with the decrease of water-cement ratio; the sulfate resistance of concrete cured for 28 days is greater than that of concrete cured for 3 days, the shorter the curing time is, the less complete the hydration process is, and the faster the deterioration rate of concrete is; the sulfate ion concentration in concrete decreases with the decrease of water-binder ratio and increases with the decrease of curing time.