Study of the Feasibility of a Damage-locating Device for Concrete Foundation Piles Using Numerical Simulation

To reuse or rehabilitate buildings damaged by earthquakes, evaluating their current state is necessary.However, because access to building foundations is usually limited, evaluating the conditions of mat foundations or piles is difficult unless building damages are clearly observed from the outside.For this reason, developing a device that can detect and quantitatively analyze foundation damage within a building is required.In this study, we propose a device to estimate the depth of pile damage by installing the device in a cast-in-place pile.Through numerical model analysis of the propagation process of the signal generated when the installed device is cracked, we investigate the feasibility of the structure of the device and the signal processing algorithm applied to the damage location.Results show that the damage location could be estimated within an error range of approximately 10% of the device length if a device having a large sensor S/N ratio as well as a damping ratio of 1% or less was installed.The factors to be considered in designing the device were derived from the simulation results.