TEMPERATURE PREDICTION OF ASPHALT CONCRETE AND CORRECTION OF DEFLECTION ON BRIDGE SLABS FOR FWD TESTING

抄録

 The authors have investigated the soundness evaluation of existing reinforced concrete (RC) slabs supported by girders using deflection at a loading point and an integrated deflection area through falling weight deflectometer (FWD) tests. In FWD tests, an asphalt concrete layer deforms locally around a loading point under an impact load. The deflection of RC slabs thus needs to be determined with an appropriate correction method. This study proposes an equation to determine the average temperature of asphalt concrete layer using a regression analysis with measured results. The results show that the proposed equation can accurately predict the average temperature by incorporating a one-hour difference in asphalt concrete surface temperature. Furthermore, the correction method of deflection using the average temperature during FWD tests proposed was analytically verified for asphalt concrete layers with temperature gradients throughout the depth. The influence of temperature gradients in correcting the deflection was also noted to be small and the previously proposed correction method was applicable to determine the deflection of RC slabs in FWD tests.