01620173

Component

https://doi.org/10.3141/2641-09

In the past few years, state transportation departments in the United States have been investigating the potential use of the traffic speed deflectometer (TSD) in routine network-level pavement structural evaluation, including efforts to compute parameters typically obtained with the falling weight deflectometer (FWD). However, differences in loading configuration (single plate versus dual tires) and mechanism (impact versus moving load) between the FWD and the TSD necessitate modification of conventional analysis methodologies for use with TSD data. The TSD is a trailer truck that uses Doppler lasers to measure the pavement deflection velocities at normal traffic speed. Deflection velocities are then converted to surface deflections with a computational algorithm. This study proposes two approaches to backcalculating layer moduli from the TSD data. The first method uses 3D-Move software and deflection velocities measured directly by the TSD. The 3D-Move software can closely simulate TSD loading by considering moving load, nonuniform contact pressure of the dual tires, and viscoelastic material properties of asphalt layers. The second method uses TSD-computed surface deflections in a linear elastic analysis backcalculation program modified to incorporate a dual-tire configuration. The two methods were evaluated with field data from the MnROAD test facility and two in-service pavement sections in Pennsylvania and Idaho. The results show that the second method can be reliably used in network-level applications until the first method becomes computationally practical. The limitations of use of the TSD deflection measurement in the conventional FWD backcalculation program was also demonstrated.

01634655

17-05027

English

pp 66–74

2017

Transportation Research Record: Journal of the Transportation Research Board

9780309441995

Digital/other

Figures (9) ; Photos; References (21) ; Tables (3)

Backcalculation; Deflection; Deflectometers; Elastic analysis; Flexible pavements; Pavement layers; Traffic speed

Idaho; Pennsylvania

Highways; Maintenance and Preservation; Pavements

TRIS, TRB, ATRI

Dec 8 2016 11:56AM

• Application of the Texas Department of Transportation Continuous Deflection Device to Select Rehabilitation Strategies for Concrete Pavements
• Assessment of Using Inertial Profilers to Measure Ride Quality on Short Projects
• Characterization of Permanent Deformation Behavior of Silty Sand Subgrade Soil Under Repeated Load Triaxial Tests
• Determination of an Optimum Backcalculation Cross Section for Unconventional Pavement Profiles
• Development of a Mean Profile Depth to Mean Texture Depth Shift Factor for Asphalt Pavements
• Dynamic Backcalculation of Viscoelastic Asphalt Properties and Master Curve Construction
• Evaluation of Moduli and Structural Coefficients of South Carolina’s Asphalt Base Mixtures
• Finite Element Framework for the Computation of Runway Friction of Aircraft Tires
• Finite Element Modeling of Permanent Deformation in the Loaded Wheel Tracker Test
• Implementation of the Structural Condition Index into the Louisiana Pavement Management System Based on Rolling Wheel Deflectometer Testing
• Implementation of the Thin Bonded Concrete Overlay of Existing Asphalt Pavement Design Procedure in the AASHTOWare Pavement ME Design Software
• Nondestructive In Situ Characterization of Elastic Moduli of Full-Depth Reclamation Base Mixtures
• Novel Macro- and Microtexture Indicators for Pavement Friction by Using High-Resolution Three-Dimensional Surface Data
• Research on Comfort and Safety Threshold of Pavement Roughness
• Simulation of Lightweight Deflectometer Measurements Considering Nonlinear Behavior of Geomaterials
• Study of Influence of Operating Parameters on Braking Distance
• Temperature Adjustment for Light Weight Deflectometer Application of Evaluating Asphalt Pavement Structural Bearing Capacity
• Wavelet Analysis to Characterize the Dependency of Vehicular Emissions on Road Roughness