PERFORMANCE OF A LOCAL PROPOSED ECONOMICAL ADDITIVE ON THE CEMENT MORTAR PROPERTIES AFFECTED BY AGGRESSIVE ENVIRONMENTAL CONDITIONS | ||||
| JES. Journal of Engineering Sciences | ||||
| Article 7, Volume 41, No 2, March and April 2013, Page 421-440 PDF (522.13 K) | ||||
| Document Type: Research Paper | ||||
| DOI: 10.21608/jesaun.2013.114743 | ||||
 View on SCiNiTO | ||||
| Authors | ||||
| A. Megahd Ahmed; M. M. Rashwan; Mostafa A.Razek* | ||||
| Civil Engineering Department, Faculty of Engineering, Assiut University, Assiut, Egypt | ||||
| Abstract | ||||
| Admixtures have long been recognized as an important components of concrete used to improve its performance. The original use of admixtures in cementitious mixtures is not well documented. It is known that cement mixed with organic matter was applied as a surface coat for water resistance or tinting purposes. It would be a logical step to use such materials, which imparted desired qualities to the surface, as integral parts of the mixture. The use of natural admixtures in concrete was a logical progression. Materials used as admixtures included milk and lard by the Romans; eggs during the middle ages in Europe; polished glutinous rice paste, lacquer, Tung oil, blackstrap molasses, and extracts from elm soaked in water and boiled bananas by the Chinese; and in Mesoamerica and Peru, cactus juice and latex from rubber plants. The Mayans also used bark extracts and other substances as set retarders to keep stucco workable for a long period of time. (ACI Education Bulletin E4-03) Chemical admixtures confer certain beneficial effects on concrete, including reduced water requirement, increased workabi1ity, control led setting and hardening, improved strength and better durability. Many approaches have been adopted to investigate the role of chemical admixtures. One approach is to determine the state of the admixture in concrete at different times of curing. The admixture may remain in a free state as a solid or in solution, or interact at the surface or chemically combine with the constituents of cement or cement paste. The type and extent of the interaction may influence the physico-chemical and mechanical properties of cement paste. In this paper an attempt is made to discuss experimentally the performance of a local proposed economical additive on cement mortar affected by aggressive environmental conditions. | ||||
|
Statistics Article View: 93 PDF Download: 171 |
||||
