中文摘要：

研究了C30、C50和C80SFIO构件在盐湖卤水-浸烘循环、现场暴露环境，无荷载和40％弯曲荷载条件下，相对动弹模量变化规律，及其微观结构演变过程。结果表明：混凝土构件在腐蚀环境下，其损伤过程包括上升阶段和下降阶段。与现场暴露环境相比，盐湖卤水-浸烘循环加速了混凝土构件的应力腐蚀；混凝土构件在现场暴露环境下的损伤过程极其缓慢。施加40％弯曲荷载混凝土构件相对动弹性模量急剧下降，趋势显著。混凝土的强度等级越高混凝土构件损伤过程越长，利用电镜分析其腐蚀产物为钙矾石和石膏，会导致混凝土构件开裂。盐湖卤水-浸烘循环-40％弯曲荷载是加速混凝土构件损伤的有效方法。

英文摘要：

The damage process ofC30,C50 and C80SFI0 structure exposed to salt lake brine-attack,salt lake exposure under 0,40% flexural loading and was systematically investigated.Environmental scanning electron microscopy（ ESEM ） was used to investigate the mi- crostructure of interior concrete.The test results showed that, concrete structure strength grade was less process included the increasing and decreasing regions.Compared with salt lake exposure, the process of concrete structure was accelerated by salt lake brine dry-immersion. The process of concrete structure damage was very slowly under salt lake exposure.40% flexural loading, then was obvious decreased con- crete structure strength grade.The damage process of concrete structure decreased with concrete strength, corrosion product by environ- mental scanning electron microscopy was ettringite and gypsum, caused the expansion of concrete structure.Salt lake-dry-immersion-40% flexural loading was an effective method to damage process of concrete structure.