盐渍地区桥梁下部结构C40混凝土抗硫酸盐腐蚀试验研究

Experimental Study of Sulfate Corrosion Resistance of C40 Concrete of Bridge Substructure in Saline Area

以盐渍地区的混凝土为对象,研究其耐硫酸盐腐蚀性能。为计算其抗压强度耐腐蚀系数,研究粉煤灰掺量为10%、20%、30%、40%、50%时对C40混凝土抗硫酸盐腐蚀性能的影响。对比研究了不同粉煤灰掺量混凝土抗压强度耐腐蚀系数、腐蚀前后质量变化系数,研究发现:随着粉煤灰掺量的增加,混凝土28 d抗压强度呈现“先上升后下降”的趋势;随着粉煤灰掺量的提高,混凝土抗压强度耐腐蚀性系数呈现“先下降后升高”的趋势;0.10FA(粉煤灰掺量10%)混凝土抗压强度可达到0.20FA(基准配合比)的111.25%,抗压强度耐腐蚀性系数可达到0.20FA(基准配合比)的111.84%,该组配合比综合性能较为优良且均衡;0.50FA(粉煤灰掺量50%)混凝土抗压强度仅为0.20FA(基准配合比)的72.42%,抗压强度耐腐蚀性系数可达到0.20FA(基准配合比)的131.58%。

This paper studies the sulfate corrosion resistance of concrete in saline area.The influence of different fly ash content on the sulfate corrosion resistance of C40 concrete is studied to calculate the compressive strength and corrosion resistance coefficient of the concrete,and the mass change coefficients before and after the corrosion are compared and analyzed.The results show that,with the increase of the fly ash content,the 28-day compressive strength of the concrete increases first and then decreases,while the corrosion resistance coefficient decreases first and then increases.The compressive strength and corrosion resistance coefficient of 0.10FA(10%fly ash)concrete can reach 111.25%and 111.84%of the 0.20FA(basic mix proportion),and the overall performance of 0.10FA is excellent and balanced.The compressive strength and corrosion resistance coefficient of0.50FA(50%fly ash)concrete can reach 72.42%and 131.58%of the 0.20FA.