A sensitivity analysis on the simulated measurements of traffic speed deflection devices

As of now, there are no standard guidelines for implementing data from Traffic Speed Deflection Devices (TSDDs) into Pavement Management Systems (PMS). This is primarily due to the complexities in analysing TSDD data. Several variables might potentially influence TSDD measurements. This study evaluates the effect of changing loading configurations, moving speed, temperature and pavement structure characteristics on the measurements of TSDDs through software modelling. The viscoelastic behaviour of the surface layer and the dynamic loads applied by all the vehicle axles are reflected in the modelling process. It is shown that pavement temperature can significantly affect TSDD measurements, primarily by changing the modulus of asphalt layer. At speeds exceeding 60 km/h, the effect of vehicle speed on TSDD measurements is negligible. Among the pavement structure characteristics, the subgrade modulus has a significant effect on TSDDs’ deflection basin. Also, this study demonstrates device-specific models for estimating critical strains from TSDD data. The proposed models are validated using field measurements from a road in the Norwegian road network.