详情

原文传递 Hardened Air in Concrete Roadway Pavements and Structures.

题名：	Hardened Air in Concrete Roadway Pavements and Structures.
作者：	desai, d. h. tikalsky, p. j. scheetz, b. e.
关键词：	air content, air void, durability, freeze, thaw, pressure meter, performance evaluation, pennsylvania, specifications, data collection, surface areas
摘要：	The objectives of this study were to (1) evaluate the validity of current Pennsylvania Department of Transportation (PennDOT) specifications for plastic and hardened air content for pavements and structures; (2) provide engineering data to correlate the relationship between plastic air measurement instruments (pressure meter), techniques that characterize the air void size and distribution including the Air Void Analyzer (AVA), and the durability of concrete to resist freeze/thaw cycles; (3) resolve PennDOT specifications differences for pavements and structural concrete; and (4) provide a new or revised specification for PennDOT 408 on air content in concrete. To provide supporting experimental evidence for the adoption of the AVA method by PennDOT, the apparatus was evaluated for its internal consistency, the consistency between it and other AVA devices of the same version, consistency between different versions of AVA, comparison between the AVA and the Rapid-Air 457, comparison with the ASTM C 231 pressure meter, and comparison with the ASTM C 666 performance-based test. The accumulated data were evaluated statistically using standard deviation and coefficient of variation. After performing the analysis of the data collected in this study from intercomparison of different instruments of the same generation, instruments of different generations, and the authors' experience with the robustness of the instrument, it was concluded that this instrument cannot serve as the basis of a specification to evaluate the air content, spacing factors or surface areas in fresh concrete at the job site. / NOTE: Final rept. (30 Jan 06-29 Jan 07). / Supplementary Notes: Sponsored by Pennsylvania Dept. of Transportation, Harrisburg. Bureau of Planning and Research. / Availability Note: Order this product from NTIS by: phone at 1-800-553-NTIS (U.S. customers); (703)605-6000 (other countries); fax at (703)605-6900; and email at orders@ntis.gov. NTIS is located at 5285 Port Royal Road, Springfield, VA, 22161, USA.
总页数：	u0715；70p
报告类型：	科技报告