Title: High Performance Lightweight Concrete--a Review

Author(s): T. W. Bremner and T. A. Holm

Publication: Symposium Paper

Volume: 154

Issue:

Appears on pages(s): 1-20

Keywords: aggregates; density (mass/volume); fire resistance; history; lightweight concretes; manufacturing; strength; thermal resistance; Materials Research

DOI: 10.14359/947

Date: 5/1/1995

Abstract:
The intrinsic nature of lightweight concrete is to produce a material which, in addition to having high strength, can also have high performance in severe service conditions. The reason for high performance is examined in light of physical, chemical, and mechanical properties of the vesicular aggregate used to produce lightweight concrete. The manufacturing process usually involves heating the aggregate to 1200 C which, in addition to rendering it more stable than conventional aggregates when concretes made from it are exposed to fire, also results in a less stiff aggregate inclusion that more closely matches the stiffness of the cement paste matrix. The use of less stiff aggregates results in a reduction in internal stress concentrations in the concrete which, in turn, leads to reduced microcracking. The role that this plays in enhancing the performance of this type of concrete is discussed in the paper. The special nature of lightweight concrete provides opportunities for design professionals. Recommendations on how best to achieve high performance concrete using lightweight aggregate are provided.