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Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
Figure 7. Example of a design chart for the hybrid system developed
using analytical and numerical methods.
4. DISCUSSION & CONCLUSION
It is apparent that the ultimate lateral response of a single
monopile foundation can be enhanced by the presence of a
footing resulting in a greater ultimate lateral capacity. This
improvement was observed at both load versus deflection as
well as the bending moment versus depth plots. Whilst the
effect on the initial lateral stiffness may not be significant, the
lateral stiffness beyond this initial movement was significantly
enhanced through the presence of the footing.
The effect of adding skirts to the hybrid system has been
shown to further increase the lateral performance of the hybrid
system, and centrifuge tests are planned to investigate the
skirted system in more detail.
A simple analytical approach using conventional lateral pile
analysis methods is presented from which preliminary design
charts can be generated. This approach can be developed to
generate realistic design charts where the lateral capacity of the
hybrid system is related to the development of bearing capacity
coupled to the lateral resistance of the pile shaft.
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