Study on pile-soil bonding condition based on transient shock response using piezoceramic sensors

The field evaluation of pile-soil combination is a key step in the service life evaluation of pile foundation. However, due to the time-varying nature of pile-soil interaction, there is no efficient method to accurately analyze it. This paper introduces a health monitoring technique for assessing the state of pile-soil bond. The transient vibration of pile-soil coupling was measured by piezoelectric ceramic sensor. In the experiment, the different bond states of pile and soil were simulated by taking clay of different density as an example. A horizontal force is applied to the top of the pile, and the induced stress wave is detected by piezoelectric ceramic intelligent aggregate sensor embedded in the pile. At the same time, taking the artificial separation of pile-soil as an example, the binding state of pile-soil is analyzed, and the influence of different soil conditions on the pile-soil bonding characteristics is studied. An energy index for quantitative evaluation of pile-soil binding quality is proposed. Taking piles buried in two layers of soil with different densities as an example, the effects of soil with different densities on pile-soil bonding characteristics were studied. Experimental and numerical results verified the effectiveness of the proposed method. The three factors influenced the pile-soil coupling. The experimental and numerical results verified the effectiveness of the proposed approach and pave the way for an approach to directly judge whether there is separation between the pile and soil and evaluate the pile safety.