The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 10, 1999
Filed:
Oct. 09, 1997
Parviz Soroushian, Okemos, MI (US);
Jer-Wen Hsu, Okemos, MI (US);
DPD, Inc., Lansing, MI (US);
Abstract
A CO.sub.2 pre-curing period is used prior to accelerated (steam or high-pressure steam) curing of cement and concrete products in order to: (1) prepare the products to withstand the high temperature and vapor pressure in the accelerated curing environment without microcracking and damage; and (2) incorporate the advantages of carbonation reactions in terms of dimensional stability, chemical stability, increased strength and hardness, and improved abrasion resistance into cement and concrete products without substantially modifying the conventional procedures of accelerated curing. Depending on the moisture content of the product, the invention may accomplish CO.sub.2 pre-curing by first drying the product (e.g. at slightly elevated temperature) and then expose it to a carbon dioxide-rich environment. Vigorous reactions of cement paste in the presence of carbon dioxide provide the products with enhanced strength, integrity and chemical and dimensional stability in a relatively short time period. Subsequent accelerated curing, even at reduced time periods (with less energy and cost consumptions) would produce higher performance characteristics than achievable with the conventional pre-setting period followed by accelerated curing of cement and concrete products.