Title: Durability of a Chloride-Saturated Concrete for Sealing Radioactive Wastes in Bedded Rock Salt

Author(s): Lillian D. Wakeley

Publication: Symposium Paper

Volume: 100

Issue:

Appears on pages(s): 587-598

Keywords: chemical properties; chlorides; concrete durability; expansion; radioactive wastes; sulfates; subsurface structures; General

DOI: 10.14359/3545

Date: 4/1/1987

Abstract:
Concrete will be a major component of isolation systems for disposal of radioactive wastes. Durability is essential for concretes used for either near-surface disposal of low-level wastes or deep underground in geologic repositories, such as the one being constructed in bedded rock salt in the southwestern United States. The factors affecting durability of these underground concretes are unique to the repository environment. Durability for these concretes must be defined in terms that are unrelated to the usual hazards encountered at the earth's surface. A concrete formulated recently for experiments underground at the Waste Isolation Pilot Plant in New Mexico is intentionally saturated with NaCl for compatibility with its host rock. It is also very high in sulfate for early and sustained volume increase. This concrete, which in standard tests or surface conditions would degrade quickly, exhibits properties in its intended environment that indicate the likelihood of durability. Chemical durability has far more meaning in this context than do the more usual indicators of concrete performance, such as compressive strength or resistance to cyclic phenomena.