الفهرس | Only 14 pages are availabe for public view |
Abstract Supplementary cementing materials (SCM’s) are commonly employed to improve the durability performance of concrete. Blends of Portland cement with SCMs are used to produce concretes for situations requiring the following conditions: high strength accelerated curing, low heat of hydration, resistance to corrosion of reinforcement, alkali silica reaction (ASR), and chemical and/or physical attack. In some cases, many, or even all, of these requirements may exist However incorporating a single SCM to improve concrete’s rheology or a specific durability property has associated limitations with its use (depending on the SCM), such as low early-age strength, extended curing periods, increased admixture use, and increased plastic shrink. Using a single SCM to address one durability concern may result in failure due to another. This research aims to study the effect of ternary blend containing two Supplementary Cementing Materials locally on concrete properties by the following: 1- Its microstructure will be reviewed as well. 2- To simulate the adverse chemical environmental in which modern-day concrete mortars are used and study the chemical resistance of ordinary Portland cement (OPC) concrete mortars IV containing two supplementary cementitious materials in contrast to control one. 3- To propose a realistic mixture proportioning of Portland cement with SCMs with optimum content to produce a durable performance concrete, based on this study. The study scope will cover blending ternary cementing material and studying its engineering properties. Using various test techniques illustrate the experimental works on fresh & mechanical properties, fluid transport, durability measurements, microstructure, and pore structure that will be applied for testing the concrete mortars according to standard specifications. The use of two types of SCMs as a ternary blend allows the effects of one SCM to compensate for the inherent shortcoming of another and has a potential to synergistically optimize the contribution of each. So the effect of blending different SCMs with cement will be resulted in improvements of the microstructure of the concrete therefore it leads to improve the durability performance of the respective binary systems. |