中文摘要：

浇筑了普通混凝土和双掺粉煤灰、矿粉两种矿物掺合料的混凝土小梁试件39个，采用螺杆对试件施加混凝土极限抗弯承载力30％和60％的持续荷载，在“氯盐溶液浸泡＋CO2环境干燥”、“去离子水浸泡＋CO2环境干燥”和“氯盐溶液浸泡＋大气环境干燥”3种不同干湿循环制度下进行干湿循环试验，分析了荷载、碳化和氯盐作用下混凝土的劣化规律。结果表明：双掺粉煤灰和矿粉的混凝土，因发生“二次水化反应”消耗了大量Ca（OH）2，其抗碳化性能比普通混凝土差；碳化后混凝土孔隙中多被CaCO3填充，孔隙率降低，因此碳化速率随碳化龄期的增长减缓；干湿循环作用下，随着循环次数的增加，对流区深度会逐渐趋于稳定，在7～9mm之间，而碳化作用使混凝土表层氯离子堆积明显；干燥过程中，氯盐存在使混凝土表面孔隙出现结晶，亦会抑制碳化反应的速率；碳化作用对混凝土中氯盐的传输起到双重作用：使混凝土孔隙率降低从而降低氯盐的传输速率，又会使部分结合氯离子释放为自由氯离子，从而提高自由氯离子含量；荷载水平由0.3倍极限荷载增加到0．6倍极限荷载，碳化和氯盐传输深度显著提高，随循环次数增加，荷载作用对碳化和氯盐传输影响愈加明显。

英文摘要：

Thirty-nine small beams with ordinary concrete and fly ash （FA） and granulated blast furnace slag （GBFS） powder mixed concrete were casted. Two kinds of sustained load with 30% or 60% ultimate load were applied on the beams, and different dry-wet cycling tests, such as immersing in NaCI solution and exposing in CO2 environment, immersing in deionized water and exposing in CO2 environment and immersing in NaC1 solution and exposing in atmosphere environment, were designed to analyze the deterioration process of concrete under carbonation, chloride attack and loading conditions. Test results indicated that the carbonation property of concrete mixed with FA and GBFS isworse than the ordinary concrete, because many Ca（OH）2 were consumed in the second hydration reaction. With the increasing of carbonation age, pores of concrete will be filled by CaCO3, hence the carbonation process slow down. In dry-wet cycling process, the convection zone will be stable at 7-9 mm. More chloride ions will accumulate at the concrete surface due to carbonation. In drying process, carbonation process will be suppressed by chloride salt crystal existed in concrete pores. Effect of carbonation on chloride transport is mainly embodied in two aspects： the transport of chloride will be suppressed by carbonation, but many of binding chloride will be released as free chloride. When the applied load increased from 30% ultimate load to 60% ultimate load, the ingress depth of chloride and carbonation increased seriously. Load effect on chloride transport and carbonation will be more obvious with the dry-wet cycling process.