中文摘要：

不同于以往混凝土硫酸盐侵蚀研究中主要采取一定浓度的硫酸盐溶液浸泡,而改用含有一定浓度硫酸盐的土壤来模拟盐渍土环境.该文研究硫酸盐溶液干湿循环作用下半插入盐渍土中单掺粉煤灰、矿粉和对比普通混凝土试件的硫酸盐腐蚀情况,并随腐蚀发展进程对试件土上和土下区域混凝土的超声声速及宏、微观腐蚀形貌和腐蚀产物进行了检测.研究结果表明盐渍土环境混凝土土上和土下区域的硫酸盐腐蚀机理和腐蚀速度存在明显不同;遭受干湿循环的混凝土土上区以物理结晶腐蚀为主,腐蚀产物为硫酸盐晶体;埋设于盐渍土中的混凝土土下区以化学腐蚀为主,腐蚀产物为钙矾石和石膏;对应不同的混凝土硫酸盐腐蚀机理,粉煤灰和矿粉所发挥的作用各自不同,即粉煤灰的掺入不利于混凝土抗硫酸盐物理结晶腐蚀,而矿粉的掺入不利于混凝土抗硫酸盐化学腐蚀;对同一种混凝土,土上区的硫酸盐腐蚀速度明显高于土下区.

英文摘要：

T he soil containing sulfate w as used to simulate saline soil environment ,and sulfate corrosion of concrete with fly ash or slag replacement and normal concrete for comparison were studied through half embedding in saline soil combining with sulfate solution wetting and drying cycles .With the proceeding of corrosion ,ultrasonic velocity ,macro‐and micro‐morphology and corrosion products of specimen concrete a‐bove and beneath soil interface were tested .The results show that the sulfate corrosion mechanism and cor‐rosion rate of concrete above and beneath soil interface in saline soil environment are obviously different . Corrosion of concrete above the soil interface belongs to physical crystallization corrosion ,and the corrosion products are sulfate crystallization .While corrosion of concrete beneath the soil interface belongs to chemi‐cal corrosion ,and the corrosion products are ettringite and gypsum .Corresponding different sulfate corro‐sion mechanisms ,effects of fly ash and slag are also different .The replacement of fly ash is not beneficial to the resistance of concrete sulfate physical crystallization corrosion ,w hile the replacement of slag is not beneficial to the resistance of concrete sulfate chemical corrosion .For the same kind of concrete ,the sulfate corrosion rate of concrete above the soil interface is significantly higher than that beneath the soil interface .