TRB Pubsindex
Text Size:
x

« Prev Next »

Return to Results | New Search

Bookmark and Share

Title:

DURABILITY OF CONCRETE AND THE IOWA PORE INDEX TEST

Accession Number:

00368277

Record Type:

Component

Availability:

Find a library where document is available


Order URL: http://worldcat.org/isbn/0309033578

Abstract:

An overview of the problem of D-cracking in portland cement concrete (PCC) is provided, and the Iowa pore index test for determining the quality of coarse aggregate for concrete is evaluated. The Iowa pore index test was developed to evaluate the durability of coarse aggregate. The test measures the amount of water that can be injected into oven-dried aggregate during a period from 1 to 15 min after application of 35 psi (241 kPa) of pressure. The test is very effective in identifying aggregates with substantial pore system of the 0.04- to 0.2-micron-diameter size and correlates very well with aggregate service records. Test results of nonhomogeneous samples can be misleading. Laboratory tests have shown that a small amount (15 percent) of unsound material in the coarse aggregate can produce nondurable concrete. Studies with the scanning electron microscope show that coarse aggregates associated with D-cracking are normally fine grained whereas durable aggregate is either coarse grained or extremely fine grained. The pore-size distribution of coarse aggregates was determined by using a mercury porosimeter. Aggregates associated with D-cracking exhibit a predominance of 0.04- to 0.2-micron-diameter pore sizes. (Author)

Supplemental Notes:

Publication of this paper sponsored by Committee on Performance of Concrete. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.

Monograph Accession #:

01411656

Authors:

Marks, Vernon J
Dubberke, Wendell

Pagination:

pp 25-30

Publication Date:

1982

Serial:

Transportation Research Record

Issue Number: 853
Publisher: Transportation Research Board
ISSN: 0361-1981

Conference:

61st Annual Meeting of the Transportation Research Board

Location: Washington District of Columbia, United States
Date: 1982-1-18 to 1982-1-22

ISBN:

0309033578

Media Type:

Print

Features:

Figures (10) ; Photos (7) ; References (6) ; Tables (1)

Geographic Terms:

Iowa

Subject Areas:

Highways; Materials; I32: Concrete

Files:

TRIS, TRB

Created Date:

Dec 30 1982 12:00AM

More Articles from this Serial Issue: