Australian Research Council Centre of Excellence Geotechnical Science and Engineering

Investigation of alternative footing shapes to mitigate the risk induced by spudcan-footprint interaction during installation of jack-up rigs

Summary

Main aims of this study are:

1. To optimise footing configurations considering following conditions

 Footing Configurations

• Skirt length / Hole or slot dimension / Spudcan underside profiles

 Geotechnical Effects

• Footprint Shape / Proximity of the spudcan to the footprint centre / Soil strength heterogeneity due to previous operational history

2. To compare the efficiency with seabed conditioning method of stomping

3. To improve & extend the design approaches recently developed for conventional spudcan to allow practitioners accurate prediction of optimized footings near existing footprints

4. To provide guidance on mitigating structural and foundation failures during jack-up installation by adjusting the footing design

Why my research is important

Spudcan-footprint interaction hazard which leads to cost implications and even potential injury is well known as one of main risks of jack-up rigs (15% of total accidents). Recent Studies have been focusing on understanding underlying behavior (Gan et al., 2012; Kong et al., 2010; Cassidy et al., 2009). However, very few mitigation methods except stomping (Jardine et al., 2002) in rule & regulation (e.g. ISO & SNAME) and JIP (e.g. InSafeJIP, 2010) results are suggested until now. Through developing the footing configuration, the risk will be efficiently and effectively minimized and safe installation of jack-up rigs will be allowed. Furthermore, the numerical methods and models developed for this study will allow for exploring similar problems in offshore geotechnical engineering.