Variability of Lightweight Aggregate Source: Effect on the Development of High Strength Lightweight SCC Matrix Blended with Normal Weight Aggregate

Abstract

Structural lightweight concrete is a valuable alternative to normal weight concrete. Concrete prepared with coarse lightweight aggregate provides reduction of a structure self-weight and better structural performance in regions prone to seismic activities. However, variability of the coarse lightweight aggregate affects production and properties of the concrete. In addition, availability of the aggregate influences the long-term use and stability in the construction industry. Lightweight aggregate is imported from Iran, Turkey, Saudi Arabia, UK, and Greece to the United Arab Emirates (UAE) and has been used in structural and non-structural applications. This paper presents the development of a self-consolidating high strength lightweight concrete (SCHSLWC) matrix with available materials in UAE. Specific gravity, unit weight, gradation, particles’ shape and absorption were used during the development and selection of aggregates source. In addition, percentage of normal weight aggregate that could be used to improve the matrix was optimized. Results of the experimental investigation showed that self-consolidating concrete mixes with more than 50 MPa cube compressive strength could be produced with aggregates having specific gravity factors in the range of 1.15 to 1.4. Additionally, up to 12% per volume of the coarse lightweight aggregate could be replaced by normal weight coarse aggregate while maintaining a unit weight less than 2000 kg/m3.