Title: Fly Ash Aggregate Lightweight Concrete

Author(s): Donald W. Pfeifer

Publication: Journal Proceedings

Volume: 68

Issue: 3

Appears on pages(s): 213-217

Keywords: compressive strength;creep properties;drying shrinkage;fine aggregates;fly ash;freeze-thaw durablity;lightweight aggregate concretes;lightweight aggregates;mix proportioning;modulus of elasticity;research;splitting tensile strength.

DOI: 10.14359/11322

Date: 3/1/1971

Abstract:
A comprehensive laboratory investigation concerning the physical properties of structural lightweight concretes containing four commercially available fly ash aggregates is presented. Air-entraining agent requirements were high when fly ash aggregate fines were used. However, when these fines were completely replaced with natural sand, the air-entraining agent requirements Due to the grading of the fly ash aggregate fines, concretes containing only coarse and fine fly ash aggregate were very harsh and difficult to cast. However, concretes containing natural sand used as a partial replacement of fly ash aggregate fines were quite workable. Since natural sand had to be used in all concretes day unit weights were limited to a about 96 lb per cu ft and increased to a maximum of about 116 Ib per cu ft depending upon the amount of natural sand fines and portland cement used. The measured physical properties of these four concretes fall within the ranges shown in the "Guide for Structural Lightweight Aggregate Concrete" of the American Concrete Institute.