Accession Number:

ADA399448

Title:

Measuring Time-Dependent Pavement Deflection Profiles Under Drive-by Conditions with a Portable System

Descriptive Note:

Final technical rept. phase 1, 11 May-11 Dec 2001

Corporate Author:

INNOVATIVE MECHANICS INC CLARENDON HILLS IL

Report Date:

2002-02-12

Pagination or Media Count:

46.0

Abstract:

Measuring pavement deflections on secondary roads permits assessment of their performance upon passage of an Army convoy. On secondary roads traffic volume is low enough to permit drive-by conditions. The system was designed accordingly. For sensing pavement deflections, linear variable differential transformer LVDT sensors were chosen. The investigation showed that in order to credibly extrapolate from sensors away from the tires to deflection underneath the tires, a laterally separated pair of sensors at each longitudinal location would be necessary. The investigation also turned up options and trade-offs regarding different methods for end-supports of the lightweight aluminum beam which would support the sensor array. Sideways-looking ultrasonic sensors for detecting tire positions both laterally and longitudinally, independently of the LVDTs, were also selected and evaluated. Overall design philosophy was not to try to zero in on the optimum right away, but to permit reasonably maximum latitude for field experimentation.

Subject Categories:

  • Civil Engineering

Distribution Statement:

APPROVED FOR PUBLIC RELEASE