Response of a stiff monopile for a long-term cyclic loading

In the Geotechnical Laboratory at Aalborg University a number of small scale tests have been performed to analyze the behavior of a rigid monopile subjected to a long-term cycliclateral loading. Only a dense state of sand is considered. A cyclic loads cause the permanent displacement of soil and rotation of a pile, effecting in the accumulated rotation and the change in soil-pile stiffness. These aspects, as poorly accounted in current standards, require thorough analysis. The design methods and a current state of art in cyclic loading field is discussed. One of the aims of the article is to validate the method established by LeBlanc (2010) in order to confirm its reliability. In addition, the results of performed tests are presented to obtain the further conclusion on the cyclic behavior of monopiles.