Influence of Shear Mode on Sand-Steel Interface Characteristics
Due to the wide application and robust stability,the jacket foundation has emerged as a predominant form for offshore wind turbine foundations.This study addresses the unidirectional shear behavior at the pile-soil interface during the installation of jacket foundations and the cyclic shear behavior encountered during service.A series of interface shearing tests were conducted on quartz sand and calcareous sand under constant stress and constant stiffness boundary conditions.Both unidirectional and cyclic shear tests were performed to assess the impact of shear mode on the sand-steel interface properties.The findings revealed that with an increase in unidirectional shear distance,the thickness of the soil breakage band gradually increases,while the roughness of the steel surface decreases.Larger cyclic shear amplitudes lead to more pronounced rearrangement of soil particles and greater normal displacement.In the process of large displacement unidirectional shearing and cyclic shearing,the breakage band alters the soil's initial interlocking,imparting a strong directionality.Due to the lower hardness of calcareous sand,its particles are more irregular compared to quartz sand of the same size,leading to greater crushing and volumetric shrinkage at same shear distance.After crushing,quartz sand develops more angular edges,making it more prone to rotation under the disturbance of steel surface,thereby increasing the dilation of the soil sample during the cyclic shearing after the large displacement unidirectional shearing.
jacket foundationinterface ring shear apparatusshear modebreakage bandinterface characteristics
万方数据
维普
