Dynamic centrifuge tests

An extensive research program was undertaken at Cambridge University to investigate the response of bridge foundations to soil liquefaction. Amain component of this research was to conduct dynamic centrifuge tests on saturated sand deposits on which model bridge pier foundations were placed. 

Coelho et al. (2007) investigated the behaviour of sandy soils of different relative density subjeeted to earthquake loading in dynamic centrifuge tests. Soil layers of 18m thickness at three different relative densities (50%, 60% and 80%) were subjected to sinusoidal earthquake loading of about 0.15g. The excess pore pressures recorded near... 

The same boundary value problem of the bridge foundation tested in the dynamic centrifuge tests was also analysed using SWANDYNE, Chan (1988). DIANA-SWANDYNE-II (Dynamic Interaction and Nonlinear Analysis-SWANsea DYNamic version II), or simply SWANDYNE, is a two-dimensional FE code created to perform static, consolidation and dynamic analysis in Geomechanics. The code uses a full effective stress-based framework to properly model the dynamic behaviour of saturated soil. The solid and pore-... 

The chapter presented the main experimental work conducted in a series of dynamic centrifuge tests on a square tunnel model embedded in dry sand. Representative experimental results have been presented and discussed. The main conclusions drawn by the interpretation of these results may be summarized as follows ... 

The series of dynamic centrifuge tests included an experiment (CT-A) intended to evaluate the fundamental behavior of the system through the analysis of a benchmark problem for further comparison with the subsequent tests. This test was also carried out to establish the influence of the bearing pressure induced by the shallow foundation on the liquefiable ground on the performance of the soil-structure system under seismic loading and to assess potential interaction effects between the structures placed in the same model. Figure 24.2 presents a scheme of the model... 

The above mechanisms were verified experimentally by carefully designed model tests and can be found in Bhattacharya (2003), Bhattacharya et al. (2004), Bhattacharya et al. (2005), and Lombardi and Bhattacharya (2014). Bhattacharya (2003) showed through dynamic centrifuge tests that axial load alone can cause a pile to fail if the surrounding soil liquefies in an earthquake and the mechanism being buckling instability. 

Harper, G.J. (1984). Evaluation of sealed containers for use in centrifuges by a dynamic microbiological test method. Journal of Clinical Pathology, 37, 1134-1139. 

Chen Z., Hutchinson T.C., Trombetta N.W., Mason H.B. Bray J.D. 2010. Seismic performance assessment in dense urban environments evaluation of nonlinear building foundation systems using centrifuge tests. In Prakash, S. (ed.) Proceedings of the Fifth International Conference on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics. University of Missouri, Rolla Rolla, MO. 

Hausler EA (2002) Influence of ground improvement on settlement and liquefaction a study based on field case history evidence and dynamic geotechnical centrifuge tests. PhD dissertation. University of California, Berkeley... 

Yang, Q.H., Yao, L.K., Ren, Z.M.. 2008. Centrifugal model test on dynamical characteristics of landslips of loose slope under seismic loading. Chinese Journal of Rock Mechanics and Engineering, 27(2) 368-374. 

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