01518638

Component

Variation in the thickness of the concrete layer is inherent in the paving process when constructing concrete pavements. To account for this variation while ensuring adequate thickness is achieved, contractors routinely make pavements slightly thicker than required. While this helps ensure pavement quality, it also adds extra materials and costs to the project without significant benefits to performance. Reducing the thickness variation associated with paving would reduce the amount of extra thickness contractors add to pavements. In order to determine the significant causes of variation and to work towards reducing thickness variation, it is necessary to have means by which to measure the extent of thickness variation. With this motivation, the nature of thickness variation in thirteen rigid pavement test cells at MnROAD was examined using an ultrasonic testing device called MIRA. Cores were taken to verify the accuracy of MIRA measurements and good agreement was found between the two. Because MIRA is nondestructive, testing was conducted at a higher rate than coring would typically allow. Thickness variation was measured in both the transverse and longitudinal directions. It was determined that the pavements at MnROAD are built thicker than designed. Trends in thickness variation were discernible because of the large quantity of data available using MIRA which would not have been obtained using coring at the typical spacing. As methods to reduce thickness variability are implemented in construction, use of these methods can be accounted for in design using new statistical methods and as part of performance based specifications.

This paper was sponsored by TRB committee AFH50 Portland Cement Concrete Pavement Construction. Alternate title: Nondestructive Evaluation of Thickness Variation at MnROAD.

01503729

14-5174

English

17p

2014

Transportation Research Board 93rd Annual Meeting

Digital/other

Figures; Photos; References; Tables

Concrete pavements; Nondestructive tests; Pavement design; Paving; Road construction; Thickness

Minnesota Road Research Project (MnROAD)

Construction; Design; Highways; Pavements; I22: Design of Pavements, Railways and Guideways; I52: Construction of Pavements and Surfacings

Transportation Research Board Annual Meeting 2014 Paper #14-5174

TRIS, TRB, ATRI

Jan 27 2014 3:48PM