Centrifuge tests investigating the effect of suction caisson installation in dense sand on the state of the soil plug

Suction caissons are a promising foundation system for offshore wind farms. However, uncertainties remain regarding the effect of the suction installation in dense sand on the load bearing behaviour. This subject is addressed here through a series of centrifuge tests, in which model suction caissons were installed in saturated fine silica sand. Following the installation, and without stopping the centrifuge, a cone penetration test was conducted inside the caisson. Comparison of the results allows relative evaluation of the effects of pumping flow rate and lid contact. Cone test results from undisturbed free field sites further provide an indication of the altered stress state inside and below the caisson. The centrifuge results indicate that the suction installation related effects on the load bearing behaviour appear to be influenced by the role of the lid contact.