外文翻译高性能混凝土的耐久性特一综述.docVIP

本科毕业设计 英 文 翻 译 院（系部） 土木工程学院 专业名称 土木工程专业 年级班级　 道桥07-4班 学生姓名　 周 鹏 指导老师 程 朝 霞 河南理工大学土木工程学院 二○一一年六月十日 The durability characteristics of high performance concrete: a review Abstract Durability problems of ordinary concrete can be associated with the severity of the environment and the use of inappropriate high water/binder ratios. High-performance concrete that have a water/binder ratio between 0.30 and 0.40 are usually more durable than ordinary concrete not only because they are less porous, but also because their capillary and pore networks are somewhat disconnected due to the development of self-desiccation. In high-performance concrete (HPC), the penetration of aggressive agents is quite difficult and only superficial. However, self-desiccation can be very harmful if it is not controlled during the early phase of the development of hydration reaction, therefore, HPC must be cured quite differently from ordinary concrete. Field experience in the North Sea and in Canada has shown that HPCs, when they are properly designed and cured, perform satisfactorily in very harsh environments. However, the fire resistance of HPC is not as good as that of ordinary concrete but not as bad as is sometimes written in a few pessimistic reports. Concrete, whatever its type, remains a safe material, from a fire resistance point of view, when compared to other building materials. Author Keywords:?Curing; Durability; Fire-resistance; Freezing and thawing; High performance concrete Article Outline 1. Introduction 2. Volumetric changes 3. Curing concrete 4. Durability 4.1. General matters 4.2. Durability in a marine environment 4.2.1. Nature of the aggressive action 4.2.2. Chemical attack on concrete 4.2.3. Abrasion resistance 4.3. Freeze–thaw resistance 5. Fire resistance of HPC 5.1. The channel tunnel fire 5.2. The Düsseldorf airport fire 5.3. Spalling of concrete under fire conditions 5.4. The Brite–Euram HITECO BE-1158 research project 6. Concluding rem