الفهرس | Only 14 pages are availabe for public view |
Abstract In the context of constructing economic robust coastal structures, this research was originated with the main objective of increasing the lifeime of concrete structures when exposed to sodium chloride. Accustomed to the defined objectives, the research study phases (i.e. methodology) were designed to encompass 4 phases (i.e.theoretical,experimental investigation, analysis and inferential phases). The 1st phase reviewed the previous literature in the field of concrete in coastal zones. Concerning the 2nd phase, the researcher proposed additives to improve the behavior of concrete (i.e. iron fillings, Sika and fiber). An experimental procedure was designed, where 24 beams were cast and immersed in 2 concentrations of Sodium Chloride for 3 intervals 1, 12 and 18 months. Investigations and measurements were carried out to define their physical and chemical characteristics. Regarding the 3rd phase, the researcher analyzed the undertaken measurements and established relationships to the concrete behavior under the different conditions. Results were discussed and compared to select the most efficient additive. Finally, in the 4th phase, the researcher deduced conclusions for implementing the most efficient additive in practice. The research concluded that the higher concentration affected seriously the concrete behavior. In general, the compression strength decreased, sulfur trioxide (So3) increased and Chloride ions (Cl-) increased, at both concentrations. The specimens cast with plastic fiber sheet proved to have the highest performance among all the tested specimens, at higher or lower concentration. The research concluded that the fibers did not provide a markedly effect at high and low concentration, in terms of Chloride ions (Cl-). Accordingly, it was suggested to implement fibers at high or low concentration (i.e. Red Sea - tunnels). |