虚心接受Development of Green High Performance Concrete for Sustainable Development
0 Introduction
Concrete is the most widely ud and the greatest amount of building materials in the con-struction area. However, extensive u of concrete has destroyed unprecedented natural resources so that resources and energy appear crisis. Concrete in ury not only meets with the re-quirements of the structure, but also minimizes asmuch as possible the damage to the ecological envi-ronment to the need of sustainable development.So, developing the green high performance con-crete is the need of the sustainable develop-ment.
1 Connotation and features of green high performance concreten
Wu Zongwei, academician of Chine academy of engineering, first propod the concept of con-crete and he pointed out the green high perfor-mance concrete was the direction of c
oncrete devel-opment. Rearchers consider the green high performance concrete should follow conditions as follows:
(1) Cement ud must be green cement. Sand and stone should be exploited orderly and withoutdamaging the environment.
(2) Cement consumption should be saved tothe greatest extent in order to reduce by-products
during the cour of producing cement, for exam-ple, CO2, SO2, and NO2and so on.
(3) Agricultural and industrial waste residueprocesd should be mixed more, such as, ground-ed slag, high-quality fly ash, silica fume and rice husk, to reduce cement, protect environment and improve concrete durability.
(4) Industrial waste liquid should be ud a lot, especially; water reducing agent made by查看系统版本 black paper waste liquid and other composite addi-tive developed should be mixed to help dealing with
other liquid.
(5) Concrete should be mixed in the mixing station to reduce waste, dust and waster water of
mixing concrete in site and waste and water recy-cling should be strengthened.
(6) Through enhancing the strength, reduc-ing cross-ctional area or volume of structure, re-ducing concrete volume, cement, sand and stone 又短又好的故事can be saved. By improving durability of concrete,rvice life of structure can be lengthened and re-pair and reconstruction cost are further saved andthe indiscriminate u of natural resources will be reduced.
(7) A lot of demolition waste should be recy-cled and recycled aggregate concrete should be de-veloped.The concept of green high performance con-推理故事crete is to strengthen people′s green awareness and to play an important role of energy saving and en-vironmental protection. It is concluded that the de-velopment of green high performance concrete is the only way for the sustainable development of concrete.
邵阳学院分数线2 Classification of the green high performance concrete
2.1 Ecological environment-friendly concrete
To meet with the requirements of high strength and high durability, traditional concrete is always in pursuit of its compactness, which will cau concrete structures (lots of buildings and rigid pavement and so on) lack of permeability and巨人传作者 permeability, exacerbate urban heat island effect,deteriorate human living environment. So rainwa-ter can not penetrate so that it lowers ground-wa-ter table in the city and affects growth of the sur-face plant, in a result, caus urban ecological sys-tem disorder. Becau concrete color is gray, living space built in concrete gives a rough, hard, cold,dark feeling. So it is concluded that the develop-ment of ecological environment-friendly concrete is the only way to solve the problems. Another, e-cological environment-friendly concrete can be di-vided into plant concrete and water-permeability concrete according to different functions.
2.2 为什么老师 Recycled aggregate concrete
Concrete from the old buildings or structures can be divided into coar and fine aggregate through breaking and this aggregate take place of some sand and gravel. So this is considered as re-cycled aggregate concrete. The u of recycled ag-gregate has been viewed as one of main measures in 蜻蜓有几只眼睛the development of green concrete.
2.3 High-volume fly ash high performance con-crete
Fly ash mixed can improve concrete’s strength, impermeability and frost resistance,lower shrinkage; inhibit the effect of the alkali-ag-gregate reaction. High performance concrete which is mixed a great deal of fly ash and the morphologi-cal effects, micro-aggregate effects, volcanic ash effects of fly ash are ud fully will lead to greater economic and environmental benefits.
2.4 Environmentally mitigatable concrete
