摘要
由于混凝土从干硬性向塑性转变 ,离析、沉降与泌水明显加剧 ,引起匀质性和稳定性下降 ;由于早强水泥和高效减水剂广泛应用 ,混凝土凝固和硬化强度发展迅速 ,初期收缩变形受约束产生很大的弹性拉应力得不到松弛则产生开裂 ,这两方面原因严重地影响处于侵蚀性环境混凝土结构的耐久性和安全性 ,迫切需要提高对这一问题的认识 ,并落实到设计、施工、材料各方面 ,使混凝土结构基础设施建设在新世纪能够可持续地发展。
Fresh concrete has been changed from stiff to plastic state,its segregation,settlement and bleeding have been pricked up markedly,and they result in lowering homogeneity and stability of concrete.On the other hand,concrete has been set and hardened fast and its strength developed quickly because of application of high early strength cement and superplasticizer,so may be cracked since drastic elastic stress developed and almost no relaxation effect occurred when shrinks was restricted at early age.Both of them affect seriously durability and safety of concrete structures in aggressive environment.It is on edge to improve the knowledge in this field,to put into effect of design,construction and material.They would play an important rule to sustainable development of infrastructure construction in this new century.
出处
《混凝土》
CAS
CSCD
2002年第6期3-5,19,共4页
Concrete
关键词
拌合物稳定性
早强混凝土
开裂性能
耐久性评价
耐久性设计
stability of mixtures
high early-strength concrete
crack performance
durability evaluation
durability design
