|Absorption of Water Test Method Aims to Reduce Chemical Damage to Concrete
Concrete can be seriously damaged by chemicals such as chlorides, sulfates and acids. Since these dangerous substances often enter concrete through sorption, it has become important in predicting the durability of concrete to know how fast chemicals can penetrate a concrete structure. ASTM Committee C09 on Concrete and Concrete Aggregates has developed a standard, the recently approved C 1585, Test Method for Measurement of Rate of Absorption of Water by Hydraulic Cement Concretes, to test how quickly substances enter concrete through sorption.
According to Chiara F. Ferraris, a physicist at the National Institute of Standards and Technology in Gaithersburg, Md., Test Method C 1585 will be useful because it will allow for a more accurate characterization of concrete, which in turn will lead to optimizing mixing designs in such a way that the amount of waste entering by sorption can be minimized. If the sorptivity coefficient can be reduced, the level of damaging chemicals that enter the concrete will decrease, making for more durable concrete.
Ferraris says that the round robin to determine the precision statement for C 1585, which is under the jurisdiction of ASTM Subcommittee C09.66 on Concretes Resistance to Fluid Penetration, is now in progress. She also notes that C 1585 allows the correct usage of service life models such as CONCLIFE, sponsored by Federal Highway Administration, and developed at NIST.
For further technical information, contact Chiara F. Ferraris, NIST, Gaithersburg, Md. (phone: 301/975-6711). C09 meets June 13-16 during the June Committee Week in Kansas City, Mo. For membership or meeting details, contact Jim Olshefsky, ASTM International (phone: 610/832-9714). //
Copyright 2004, ASTM International