Short- and Long-Term Evaluation of Asphalt Concrete Strain Gauge Installation Methods Applied to the KHCTR

Abstract

In the present study, three strain gauge installation methods (mound, trench-cut, and block-out) are evaluated to propose a set of methods that are appropriate for different layers of hot mix asphalt (HMA) pavements. The block-out method is also improved to minimize strain gauge mislocations (i.e., installation offsets). Field tests show that the improved block-out method is suitable for most layers, except for a thin surface, for which the mound should be used. To validate the proposed methods, 374 strain gauges are installed at different layers of thirty-three HMA pavement sections (48 in surface, 157 in intermediate, and 169 in base) at the Korea Highway Corporation Test Road (KHCTR) and their initial and long-term performances are monitored at different times. In addition, the failure rates of the embedded strain gauges are correlated with the evolution of the overall pavement conditions and key distresses at selected sections from 2003 to 2007.