铜尾矿砂对C50混凝土力学性能和耐久性的影响

用铜尾矿砂替代部分天然砂配制C50混凝土,研究其掺量对C50混凝土力学性能、抗氯离子渗透性、干燥收缩性能及抗冻性的影响。结果表明:当铜尾矿砂掺量为10%~30%时,混凝土各龄期抗压和抗折强度均随铜尾矿砂掺量的增加而逐渐提高;当铜尾矿砂掺量为40%时,混凝土的7d、28d抗压和抗折强度与天然砂混凝土相当。铜尾矿砂的掺入能提高混凝土的抗冻性和抗氯离子渗透性;随着铜尾矿砂掺量的增加,铜尾矿砂混凝土各龄期的干燥收缩率显著增大。

Influence of copper tailings sand on the mechanical properties and durability of C50 concrete

Copper tailings sand was used to replace natural sand in the preparation of C50 concrete,and the influence of different content of copper tailings sand on the mechanical properties,chloride permeability,drying shrinkage and frost resistance performance the C50 concrete was investigated. The results show that the compressive strength and flexural strength of C50 concrete at different curing times increased with the increasing copper tailings sand content when the substitution was bewteen 10% and 30%,while the 7 d,28 d compressive strength and flexural strength of C50 concrete were equal to that of natural sand concrete when the substitution was 40%. The addition of copper tailings sand could improve the frost resistance and chloride permeability of the concrete,with the increase of the copper tailings sand substitution,the drying shrinkage of the copper tailings sand concrete at different curing ages increased significantly.