Utilisation of the deflectograph data to evaluate pavement structural condition of the highway network

The evaluation of the structural condition of the highway network is of paramount significance for highway network asset managers. Pavement surface deflection has been used by several highway agencies to assess the structural condition of pavement structure. Falling weight deflectometer, deflectograph and other devices are commonly used to measure the deflected shape of the pavement surface under loading. Researchers have developed several parameters that can be derived from the measured deflection bowl to assess the pavement structural condition. In this research paper, the measured deflection using the deflectograph is used to evaluate the structural condition of the pavement network. Area ratio and normalised area ratio parameters were derived from the measured deflection. It was found that the normalised area ratio provides a very good and stable evaluation of the structural condition of the road network. It was also found that the normalised area ratio is well correlated with the normalised deflection ratio. The normalised area ratio for different flexible pavement compositions and structural conditions was developed by computer simulations to provide an evaluation of the structural pavement condition.