外文翻譯--未來(lái)的混凝土自密實(shí)混凝土（有word版的）

1、 BULETINUL INSTITUTULUI POLITEHNIC DIN IASI Publicat de Universitatea Tehnica ,Gheorghe Asachi” din Iasi Tomul LVI (LX), Fasc. 2, 2010 Sectia CONSTRUCTII.ARHITECTURS THE FUTURE CONCRETE: SELF- COM

2、PACTING CONCRETE Abstract. The paper presents the characteristics of the self- compacting concretes, their advantages and disadvantages when they are used in buildings. Due to its properties and

3、composition, the self- compacting concrete is described here as being one of the future friendly enviromental material for buildings. Tests concerning to obtaining a self- compacting concrete, toge

4、ther with the specific fresh concrete properties tests, are described. Key words: self- compacting concretes; enviromental friendly materials; fly ash; durability. 1. General Considerations about Sel

5、f- Compacting Concretes 1.1. Introduction The concrete is the man- made material which has the vastest utilization worldwide. This fact leads to important problems regarding its design and preparat

6、ion to finally obtain an economic cost of the product on short and long time periods. The material has to be also “friendly with the environment” during its fabrication process and also its

7、 aesthetical appearance when it is used in the structures. Its success is due to: a) its raw materials that have a large spreading into the world; b) the prices of raw materials that are l

8、ow; c) the properties and the performances of the concrete that confers it a large scale of application. carried out from the viewpoint of making it a standard concrete. Recommendations and m

9、anuals for self- compacting concrete were also written [1]. To make durable concrete structures, sufficient compaction by skilled workers is required. However, the gradual reduction in the number

10、of skilled workers in construction industry has led to a similar reduction in the quality of construction work.. One solution for the achievement of durable concrete structures, independent of

11、the quality of construction work, is the use of the SCC, which can be compacted into every corner of a formwork, purely by means of its own weight and without the need of vibrating compact

12、ion (Fig. 1) [1]. In Japan, in the year 1988, SCC emerged on the scene and it has been the subject of numerous investigations in order to adapt it to modern concrete production. At the sa

13、me time the producers of additives have developed more and more sophisticated plasticizers and stabilizers tailor- made for the precast and the ready- mix industry. Fig. 1 – Necessity of Self- Co

14、mpacting Concrete[1]. For last 20 years, the problem of the durability of concrete structures was a major topic of interest. SCC is a concrete which flows to a virtually uniform level under

15、the influence of gravity without segregation, during which it de- aerates and completely fills the formwork and the spaces between the reinforcement [2]. It is a high- performance concrete with

16、the special property of the fresh concrete of “self- compacting”. As with other high- performance concretes (e.g. high- strength concrete, acid- resistant concrete) the special properties of these c

17、oncretes, which differ from normal concretes, are achieved only by systematic optimization both of the individual constituents and of the composition. The flow ability and mix stability of the

18、SCC are determined primarily by the interactions between the powder (cement and additions with a particle diameter < 0.125 mm), water and plasticizer. The gradation of the individual size gro

19、ups in the overall grading curve also affects the property of the concrete in the sense of not being blocked by the reinforcement. It has been found that, in contrast with vibrated concrete,