DERIVATION OF PAVEMENT MATERIAL VARIABILITY FROM NONDESTRUCTIVE TESTING. SIXTH INTERNATIONAL CONFERENCE, STRUCTURAL DESIGN OF ASPHALT PAVEMENTS, VOLUME I, PROCEEDINGS, UNIVERSITY OF MICHIGAN, JULY 13-17, 1987, ANN ARBOR, MICHIGAN
In pavement evaluation using nondestructive testing (NDT), a large amount of deflection bowls are analyzed in terms of the elastic moduli of the layers. The results are used to evaluate the material variability, which could serve in an overlay design procedure based on the concept of reliability. The model currently used for interpreting deflection bowls is based on the random variable theory which neglects the spacial distribution of the elastic modulus of the material. Since the subgrade and pavement materials have a spacial distribution, the analysis of NDT could lead to an underestimate of the material variability. The random field theory, which is more adequate than the random variable theory, is presented and used to correct the NDT analysis. The theoretical approach is limited to the small variation range (i.e. coefficients of variation up to 30 percent). Two cases, the Boussinesq and the two-layer system, are analyzed with the random field theory, and the covariance matrix of the deflection bowl is obtained and used to generate deflection bowls corresponding to the properties of the random field. These bowls are then interpreted with the current procedure and elastic modulus variabilities are computed. It is found that the current procedure for interpreting deflection bowls underestimates the variability of the subgrade, by a factor of 0.4 to 1.0. It is interesting to note that the average moduli of the Boussinesq layer and of the two layers are not affected by the type of theory used. The variability of the upper layer in the two layers system is also unaffected (for the small variation range). Figures for correcting the variability obtained from NDT results are presented. The methodology is illustrated and discussed.
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Corporate Authors:
University of Michigan, Ann Arbor
Department of Civil Engineering
Ann Arbor, MI United States 48109 -
Authors:
- Uzan, J
- Zeitoun, D G
- Baker, Rogis
- Publication Date: 1987
Media Info
- Features: Figures; References; Tables;
- Pagination: p. 533-542
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Serial:
- Publication of: Michigan University, Ann Arbor
- Publisher: University of Michigan, Ann Arbor
Subject/Index Terms
- TRT Terms: Asphalt pavements; Boussinesq equation; Conferences; Covariance; Deflection; Evaluation; Modulus of elasticity; Nondestructive tests; Pavement layers; Pavement performance; Pavement subgrade; Pavements; Variables
- Old TRIS Terms: Boussinesq formula; Pavement deflection; Random field theory; Two-layer systems
- Subject Areas: Design; Highways; Pavements; I22: Design of Pavements, Railways and Guideways;
Filing Info
- Accession Number: 00485621
- Record Type: Publication
- Files: TRIS
- Created Date: Jul 31 1989 12:00AM