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Title:

Evaluating Specification Limits
Cover of Evaluating Specification Limits

Accession Number:

01031139

Record Type:

Component

Availability:

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Order URL: http://worldcat.org/isbn/0309099544

Abstract:

The results of a study to evaluate the existing South Carolina Department of Transportation (SCDOT) hot-mix asphalt quality assurance specification are presented. When the existing specification was developed, assumed values were used for the standard deviations needed to establish the specification limits. Acceptance test results from 39 different projects were analyzed to determine standard deviation values that were being obtained for asphalt content, air voids, voids in mineral aggregate, and density. For each project, standard deviation values were calculated for each lot, and these were then pooled to obtain a typical value for the project. The target miss variability, that is, the ability of contractors to center their processes on the target, was also determined for each acceptance characteristic. The project and target miss values were then used to establish a typical process standard deviation value for each of the four acceptance characteristics. All these standard deviation values proved to be smaller than those initially assumed and resulted in the SCDOT narrowing the specification limits for each of the acceptance characteristics. The project standard deviation values justified that these changes were made to reflect the actual variability that was present and not simply to tighten the specifications.

Monograph Title:

Construction 2006

Monograph Accession #:

01031140

Language:

English

Authors:

Burati Jr, James L

Pagination:

pp 92-98

Publication Date:

2006

Serial:

Transportation Research Record: Journal of the Transportation Research Board

Issue Number: 1946
Publisher: Transportation Research Board
ISSN: 0361-1981

ISBN:

0309099544

Media Type:

Print

Features:

Figures (5) ; References (8) ; Tables (4)

Subject Areas:

Construction; Highways; I50: Construction and Supervision of Construction

Files:

TRIS, TRB

Created Date:

Aug 22 2006 11:42AM

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