Research On Horizontal Bearing Characteristics Of Offshore Wind Power Three-Bucket Foundation

Bucket foundation is a new type of offshore foundation with closed top and open bottom.Bucket foundation is playing an increasingly important role in coastal engineering because of its advantages of reusable,investment saving and construction time shortening.The research on bearing capacity variation of three-bucket foundation under unidirectional load is not perfect.Based on the above problems,this paper through the model test of three small size tube based load-bearing characteristics for more in-depth research,by changing the tight skirt and the Angle of height,load,speed,load,drainage way influence factors,explore its the ultimate bearing capacity for foundation level three,drum week,variation in the earth pressure cylinder base internal pore water pressure change rule.The ABAQUS finite element software was used for modeling and analysis to verify the correctness of the test.Meanwhile,the distribution law of plastic zone and deformation law of soil around the three-bucket foundation were analyzed in detail.The main research contents and results of this paper are as follows:Based on laboratory tests,the influence of different tube skirt height on the horizontal bearing capacity of three-bucket foundation was explored.The test results show that,under the condition of no drainage,the larger the length to diameter ratio of the tube skirt is,the greater the bearing capacity will be,and the horizontal ultimate bearing capacity of three-bucket foundation in the direction of 0° loading will increase more.Through the comparative analysis of the horizontal bearing capacity of the threebucket foundation with different loading speeds,it can be seen that when the height of the cylinder skirt is consistent with the loading Angle,the higher the loading speed is,the higher the horizontal ultimate bearing capacity of the three-bucket foundation is under the condition of no drainage.Under the condition of drainage,because the loading speed is small on the whole,the increase of loading express on the horizontal ultimate bearing capacity of three-bucket foundation is limited.Based on laboratory tests,it is found that the loading Angle and drainage mode also have great influence on the horizontal bearing characteristics of three-bucket foundation.Under the condition of drainage,the horizontal ultimate bearing capacity of the three-bucket foundation with the height of 350 mm and 250 mm in the direction of 0° loading is increased by 155% and 68%,respectively,compared with that of150 mm.The horizontal ultimate bearing capacity of the three-bucket foundation with the loading Angle of 0° is higher than that with the loading Angle of 180°.Different loading angles have great influence on the earth pressure value of the bucket,especially in the passive earth pressure area around the bucket.Compared with drainage condition,the maximum increase of horizontal ultimate bearing capacity of three-bucket foundation without drainage is 182%,and the pore water pressure under compression bucket increases obviously,while that under tension bucket decreases obviously.The horizontal bearing characteristics of three-bucket foundation were analyzed by model test and numerical simulation.It was found that according to the distribution law of plastic zone around the bucket,the plastic strain value of soil around the compression bucket was greater than that around the tension bucket.According to the law of soil deformation,the analysis shows that the failure mode of three-bucket foundation is tension-compression failure mode.