摘要
根据典型构件应力状态,针对性的开发应力、裂缝宽度易于控制且精度高的加载试验装置,在人工海水模拟环境下,研究了单轴压荷载、弯曲荷载以及不同宽度结构裂缝对海工高性能混凝土抗氯离子扩散性能的影响。结果表明:单轴压荷载应力水平小于30%时,混凝土抗氯离子扩散能力随着荷载水平增加而提高,至50%时出现降低;弯曲荷载作用降低混凝土抗氯离子扩散能力,当荷载水平较大时,荷载水平的增加将导致抗氯离子扩散能力的急剧下降;裂缝的出现使得混凝土中不同深度处的氯离子浓度都得到相应的提高。据此,分析得出荷载对海港工程混凝土耐久性的影响不容忽视,提出设计中采用预应力尤其是先张法预应力混凝土对提高结构耐久性能有利。
An effective loading device, with which different loads and cracks can be conducted easily and accurately, was designed ac- cording to actual stress state of typical marine elements. Influences of constant uniaxial compressive load, flexural load and structural cracks with different width on chloride penetration resistance in high performance concrete of harbor engineering were investigated under artificial simulated seawater curing condition. The results reveale that the chloride penetration resistance increases with the increase of compressive load level when the level is lower than 30%.When it reaches 50% ,the chloride penetration resistance becomes to decrease. The flexural loads decrease the chloride penetration resistance. When the load level is high, the increase of the level leads to rapid deteri- oration of the chloride resistance.The chloride concentration of concrete at different depth becomes higher due to the cracks.According to the research, it is obvious that the influence of load on marine concrete structure durability is unneglectable.Based on the study, pres- tressed concrete ,especially pretensioning prestressed concrete is recommended to improve the marine concrete structure durability.
出处
《混凝土》
CAS
北大核心
2016年第4期4-8,共5页
Concrete
基金
国家交通运输部科技项目(2011-32849A1140)
国家科技部科研院所技术开发研究专项(2013-EG124049)
关键词
海港工程
弯曲荷载
压荷载
裂缝
氯离子
先张法预应力混凝土
harbor engineering
flexural load
compressive load
crack
chloride ion
pretensioning prestressed concrete
