Title: Some Properties of Crude Oil-Soaked Concrete--Part I, Exposure at Ambient Temperature

Author(s): O. A. Onabolu

Publication: Materials Journal

Volume: 86

Issue: 2

Appears on pages(s): 150-158

Keywords: absorption; compressive strength; concrete durability; concretes; crude oil; curing; deterioration; drying; fly ash; long-time study; microstructure; mortars (material); offshore structures; pozzolans; salts; saturation; seawater; specimens; storage tanks

DOI: 10.14359/2319

Date: 3/1/1989

Abstract:
Concrete tanks are used to store crude oil on land as well as offshore. In the latter case, the tanks are incorporated into the platform structures and are located at its base. Under service conditions, the mechanical properties of the material may be impaired with time, thereby compromising the durability of the storage tanks and the serviceability of the structure. The variations in compressive strength, length change, and absorption characteristics of typical offshore concrete exposed to crude oil for 365 days have been investigated. They are reported in two series: exposure to crude oil at ambient temperature of about 20 C, and exposure at elevated temperatures of 45, 60, and 80 C. Studies have shown that the factors significantly affecting these properties are the curing conditions of the concrete prior to exposure, moisture conditions of the concrete at the time of exposure, and the temperature of storage of the crude oil. It has been found that the presence of pulverized fuel ash (pfa) in the concrete increases its resistance under exposure condition. This may be related to changes in the pore structure resulting from pozzolanic activities, as well as to the effect of "packing" of pfa particles in the microstructure.