Title: Durability of Lightweight Concrete Containing High Volume Fly Ash and Highly Porous Bottom Ash

Author(s): M. Nisnevich, G. Sirotin and Y. Eshel

Publication: Symposium Paper

Volume: 234

Issue:

Appears on pages(s): 703-720

Keywords: bottom ash; cement; crushed sand; durability; fly ash

DOI: 10.14359/15967

Date: 3/22/2006

Abstract:
Proportions, properties and technological parameters of lightweight concretes containing high volumes of fly ash and highly porous bottom ash were studied at the Research Institute of the College of Judea and Samaria (Ariel, Israel). According to properties of coal ashes and requirements of density, strength and durability of the lightweight concrete, the following types of lightweight concrete were developed: (a) a binary concrete containing fly ash and bottom ash (used as an aggregate); (b) a ternary concrete containing fly ash, bottom ash and unprocessed crushed sand which is a common by-product of crushed stone quarries (the two last products were used as aggregates). Incorporation of these constituents in an optimum proportion enables the production of lightweight concrete with required properties of density, strength and durability. One especially desired product is a ternary concrete, which is free of the following drawbacks of the binary concrete: (a) insufficient strength and durability; (b) relatively high activity concentrations of undesirable radionuclides presented in coal ashes. A study of properties of the ternary concrete under laboratory and field conditions confirmed its effectiveness as thermal-insulating/structural and structural material. The current paper presents results of a study of the durability of ternary lightweight concrete, conducted under Mediterranean climate conditions, characterized by a very hot summer with temperature extremes (especially in the desert regions) and very wet winters with prolonged rains.