矿物掺合料对腐蚀混凝土强度影响及关联分析

结合赣南区域稀土开采残留硫酸铵的环境问题，在后期土地开发的背景下，通过对粉煤灰混凝土、矿渣混凝土、双掺混凝土受硫酸铵腐蚀的试验，测定受腐蚀混凝土的力学性能，分析受腐蚀混凝土强度劣化的规律，并运用灰色关联分析理论对不同掺量矿物掺合料混凝土强度进行关联度分析。结果表明混凝土中掺入粉煤灰和矿渣等量替换水泥能显著提高混凝土抗硫酸铵腐蚀性能;大掺量矿物掺合料的混凝土强度增长较慢，但抗硫酸铵腐蚀能力较好;矿物掺合料对受腐蚀混凝土的抗压强度衰减有较好延缓效果，但对抗折强度的延缓衰减的效果较差;通过灰色相关理论得粉煤灰掺量10%，矿渣掺量40%和50%腐蚀混凝土的总体强度与未腐蚀混凝土强度关联度达到80%，抗硫酸铵腐蚀效果最佳，与试验结果一致。

Influences of Mineral Admixtures on the Strengths of Corroded Concrete and Corresponding Correlation Analysis

In view of the environmental problem of ammonium sulfate residue caused by rare earth mining in the southern part of Jiangxi , we tested the mechanical properties of corroded concrete and analyzed the regularity of
strength deterioration of corroded concrete through tests of corrosion ( by ammonium sulfate solution ) on concretes mixed with fly ash , slag , and both fly ash and slag , respectively .Furthermore , we employed the theory of gray cor-relation to analyze the correlation between strength and mineral admixtures of concrete .Results show that the con-crete mixed with fly ash and slag replacing cement in equal amount could significantly increase the resistance of concrete to ammonium sulfate corrosion; the strength of concrete with high content of mineral admixtures grows slowly, but the resistance to ammonium sulfate corrosion is better;mineral admixtures have good effect in delaying the decline of compressive strength of corroded concrete , but shows worse effect for flexural strength .The results of grey analysis reveal that concretes C 1 (10%dosage of fly ash), C4 (40%dosage of slag), and C5 (50%dosage of slag ) have the best performances in resisting ammonium sulfate corrosion .