The Effect of Embedment on the Seismic Response of a Pile Group in Clay: Insights from 1-g Shaking Table Tests

1. Home
2. Publications
3. Online Library
4. The Effect of Embedment on the Seismic Response of a Pile Group in Clay: Insights from 1-g Shaking Table Tests

Understanding the seismic response of pile supported structures during an earthquake is key to the design of resilient infrastructure.  Kinematic soil-pile interaction is known to cause considerable alteration to the Foundation Input Motion experienced by a pile supported superstructure. Although soil-pile interaction has been rigorously investigated in the past, the influence of an embedded pile cap is often ignored due to the uncertainties in fill material and construction techniques. This paper presents results from a shaking table study on two 2x2 model pile groups in clay. The two model pile group models, one embedded and the other free standing, installed in the same laminar shear box, were subjected to a series of harmonic and white noise signals. The responses in terms of the ratio of transfer functions and spectral ratios were employed to identify the influence of cap embedment. Data smoothing methods employing time windowing and coherence functions were used to identify the transfer functions from the white noise excitation. The ratio of responses of the two models in frequency domain, obtained from both harmonic and white noise excitations were found to follow a similar trend.  Significant reduction in the amplitude of translational acceleration, of up to 50% was observed after a certain threshold frequency. The experimental evidence points at a significant high frequency filtering due to embedment, in addition to the filtering due to kinematic soil-pile interaction .

4th Asia-Pacific Conference on Physical Modelling in Geotechnics (ACPMG2024)

Other