Long-term measurement stability of domestic pavement traffic speed deflectometer

With the rapid development of infrastructure, the demand for road maintenance and monitoring work is increasingly urgent. Pavement deflection, as a key indicator of road structural performance, is crucial for engineering quality control. Traditional deflection measurement methods, due to their low efficiency, can no longer meet current needs, while the emergence of laser dynamic deflection measurement technology has brought revolutionary changes to road detection. This paper studies the long-term measurement performance of the domestic pavement Traffic Speed Deflectometer (TSD), especially their accuracy and time stability. The assessment is carried out through two key indicators: repeatability and correlation with the Falling Weight Deflectometer (FWD) measurements. The research found that after five years of use, the tested TSD still shows good measurement repeatability and maintains a high correlation with the FWD measurement results. This indicates that the equipment has excellent long-term stability and reliability, suitable for large-scale road deflection measurement work across the country.