Title: Corrosion of Steel in Lightweight Concrete Specimens

Author(s): S. B. Helms and A. L. Bowman-

Publication: Journal Proceedings

Volume: 65

Issue: 12

Appears on pages(s): 1011-1016

Keywords:

DOI: 10.14359/7533

Date: 12/1/1968

Abstract:
Severe corrosion of reinforcement in channel slabs of a roof structure was reproduced by cyclic exposure of labora-tory molded prisms and cylinders containing steel inserts. Earlier studies using small cylinders showed that the first indications of corrosion would be evident after 50 cycles of wetting and drying. Specimens exposed to daily cycles involving directional exposure to condensation and saturation at elevated tem-peratures show 100 cycles adequate to determine the ab-sence of any corrosive tendency. While the presence of two percent calcium chloride may not be corrosive in more favorable environments, the re-sults indicate that for severe exposure to moisture and temperature changes the safe practice is to use materials known to be free of chlorides. Inserts in control specimens containing no chloride accelerator were free of corrosion, with either of two types of lightweight aggregates, even after 150 cycles of exposure.