Dynamic backcalculation with different load-time histories

Abstract

This paper focused attention to the Falling Weight Deflectometer (FWD) load-time history. For a commonly used device, it studied the pulse generation mechanism and the influence of different load histories on backcalculation results. In this connection, a semi-analytic impact theory was first introduced for realistically simulating FWD pulse generation. Then a newly developed finite element code was presented for FWD interpretation; the code is capable of addressing dynamics, timedependent layer properties, and quasi-nonlinear behavior. Both new developments were demonstrated for an experimental dataset that resulted from operating an FWD with different loading configurations. It was found that backcalculated parameters are sensitive to the FWD pulse features. Consequently, it is recommended that, whenever advanced pavement characterization is sought, experimental attention should be placed on generating diverse FWD pulse histories. Collectively, the resulting deflection histories will contain pertinent constitutive information for supporting the calibration of more complex pavement models.

Multi Modal Dynamic Linear Viscoelastic Back Analysis for Asphalt Mixes

“…Back analysis methods are used for different applications on pavement [33,34]. The proposed combined back analysis is based on the analysis of the first resonance peak for each temperature and for each mode of vibration.…”

Analysis of a moving measurement platform based on line profile sensors for project-level pavement evaluation

“…For this purpose the pavement system is typically modeled as a weightless stratified linear elastic half-space having a priori known layer thicknesses and interface conditions (SPT1026; SPT1198; SPT1375). Although more advanced interpretation schemes exist (see e.g., Chatti, Ji, and Harichandran (2004); Madsen and Levenberg (2018); Varma, Kutay, and Levenberg (2013)), none have yet to gain widespread engineering acceptance similar to the elastostatic backcalculation.…”

Efficient reevaluation of surface displacements in a layered elastic half-space

“…These modern devices are essentially custom-built trucks, heavily instrumented with sophisticated sensory gear, expected to traverse pavement networks at highway speeds and record surface displacements generated by their own presence. The usual approach for performing the inverse analysis involves mechanical modeling of the pavement system, forward-simulating the applied loading and resulting displacements, and then identifying the layer properties by best fitting simulated displacements with their respective measurements (e.g., Madsen and Levenberg 2017).…”