Durability of High Performance Concrete With Fly Ash

Abstract

High-performance concrete (HPC) is usually produced using high quality materials. These high quality constituents drastically increase the initial cost of HPC, hence hindering its more widespread use. Therefore, the main goal of this research project was to produce a low cost enhanced performance concrete or even a low cost HPC, using low quality fly ash and locally available crushed aggregates. In this way, a significant reduction in the use of Portland cement, as well as that of scarce natural resources, would be obtained. The effect of high percentages of fly ash and crushed aggregates on concrete performance was studied by comparing the mechanical and durability performances of such concretes with nominally similar types of concrete with no fly ash incorporated. The results obtained indicate that it is possible to produce concrete in the low range of HPC with up to 65 MPa at 56 days by replacing up to 40% of cement with as received fly ash using crushed granite aggregates. Furthermore, it was observed that workability and durability both increased significantly when fly ash partially replaced Portland cement.

Mix design approach for high 28 days’ strength, high-volume, low-lime fly ash concrete

“…Moreover, about 35% reduction in compressive strength was observed on day 28 (Malhotra & Ramezanianpour, 1994). Reduction in compressive strength at 28 days was also reported by other authors (Barryman, Zhu, Jensen, & Tadros, 2005;Camoes, Aguiar, & Jolali, 2003;Jiang, Liu, & Ye, 2004;Oner, Akyuz, & Yeldiz, 2005;Ravina & Mehta, 1988;Siddique, 2004;Zang Sun, & Shang, 1997). Mehta's (2004) study, compared high-volume fly ash concrete with low-lime fly ash having water-cement ratio of 0.39 with only cement concrete with water-cement ratio of 0.58.…”

Prediction and multi-objective optimization of high-strength concrete parameters via soft computing approaches

“…In Europe, HSC is considered to be a concrete having a high-strength at 28 days (typically >60 MPa compressive strength) or a low water-binder ratio (<0.40). In USA, HSC is supposed to be a special mixture, matching specific requirements that cannot be achieved on a routine basis (Camoes, Aguiar, & Jalali, 2003). In Turkey, HSC is considered to be a concrete having a minimum compressive strength of 40 MPa at 28 days (Özkul, Tasdemir, Tokyay, & Uyan, 1999).…”

Combined Economic and Mechanical Performance Optimization of Recycled Aggregate Concrete with High Volume of Fly Ash

“…As with this study, it showed that the cost slightly decreased (42 €/m 3 for C30/37 and 48 €/m 3 for C50/60) when RCA was used. Furthermore, other studies [5,37,38] reported that the cost of concrete significantly decreased by using FA. Figure 5 presents the relationship between compressive strength and cost of 1 m 3 of concrete for the concrete mixes in this study (M1-M18sp) and commercial concrete mixes obtained from Portuguese suppliers [35].…”