德令哈盐沼泽区桥梁墩台混凝土损伤试验研究

发布时间：2018-01-14 22:34

本文关键词：德令哈盐沼泽区桥梁墩台混凝土损伤试验研究　出处：《长安大学》2015年硕士论文　论文类型：学位论文

更多相关文章： 混凝土 桥梁墩台 盐沼泽 损伤失效

【摘要】：随着混凝土结构的广泛应用,混凝土耐久性问题日渐突出,目前针对混凝土耐久性问题国内外已有大量研究,但对盐沼泽地区混凝土腐蚀问题的研究结果与观点至今仍未统一。在西部寒旱地区盐沼泽环境下,高矿化度的地表水、地下水及盐渍化土形成复合盐类强腐蚀环境,且存在干湿循环和冻融循环的耦合作用,因而西部地区混凝土结构的耐久性问题显得尤为复杂,还需深入研究。本文依托德香高速公路,对其沿线盐沼泽地区土质进行分析,配制腐蚀溶液;结合实际施工及桥梁结构混凝土耐久性基本要求,设计四种配合比混凝土:基准混凝土、掺加10%粉煤灰混凝土、掺加20%粉煤灰混凝土以及掺加1.5%水泥基自愈合材料(CCSM)混凝土,结合其寒旱气候特征,进行了长期浸泡试验、盐蚀-干湿循环试验和盐蚀-冻融循环试验,结果表明混凝土盐溶液浸泡腐蚀是一个长期缓慢的过程;掺加水泥基自愈合材料、粉煤灰能够提高混凝土抗盐蚀-干湿循环的破坏能力;在盐蚀-冻融循环中,复合盐对混凝土的冻融破坏作用同时存在促进作用和抑制作用,在低浓度盐溶液中,盐的存在加剧了混凝土的冻融损伤,在高浓度盐溶液中,溶液冰点很低,缓解了混凝土冻融损伤,掺加水泥基自愈合材料的混凝土表现出了良好的抗盐冻性,粉煤灰混凝土抗盐冻性能较差,且粉煤灰掺量越大,混凝土抗盐冻性能越差。
[Abstract]:With the wide application of concrete structure, concrete durability problems have become increasingly prominent, the domestic problems of durability of concrete has been studied, but the unified investigation results of concrete corrosion problem of salt marshes area and views. Yet in the western arid region of salt marsh environment, high salinity of surface water, groundwater and soil salinization the formation of composite salts of strong corrosive environment, and dry wet cycle and freeze thaw cycle coupling, so the durability of the concrete structure in the western region is very complicated and needs further study. This paper according to Todd Shannon highway, the salt marshes along the soil analysis, preparation of corrosion solution; combined with the basic requirements of actual construction and concrete bridge structure durability design, four kinds of concrete with reference concrete, mixed with 10% fly ash concrete with 20% fly ash concrete And adding 1.5% of cement based self healing material (CCSM) concrete, combined with the cold and arid climate characteristics, the long-term immersion test, salt corrosion - dry wet cycle test and the salt erosion and freeze-thaw cycle test, results show that the corrosion of concrete in salt solution is a long slow process of self healing material; adding cement base fly ash can improve the ability of damage, concrete anti salt corrosion - wet dry cycle; in - salt corrosion during freeze-thaw cycles, compound salt on the freeze-thaw damage effect existed at the same time enhancement or inhibition of concrete, at low salt concentration, salt intensifies the freeze-thaw damage of concrete, at high salt concentration. In the solution, the solution freezing point is very low, alleviate the damage of concrete freeze-thaw self healing material concrete showed good frost resistance by adding cement, fly ash concrete frost resistance is poor, and the greater the fly ash, salt resistant concrete The worse the frost performance.

【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U446

【相似文献】