Analysis Of Ultimate Depth And Bearing Capacity Of Vertically Loaded Anchors With Bridle Shank

The Vertically Loaded Anchors provide an attractive alternative to the mooring system because of its convenient installation process,recyclable recycling,low cost and good bearing performance.Quantitative determination of the ultimate depth of the anchor is important because it essentially determines the bearing capacity of the anchor.Through the analysis of the operation mechanism of the anchor,a method for determining the state of the reconfigurable flexible anchor during the motion is established.Combined with this method,Maple is used to write the calculation program,and the plastic method is introduced.The yielding surface equation and the anchor chain equation are used to solve the composite load of the normal bearing anchor movement,and the calculation is based on the definition of the displacement calculation method in the associated flow rule.The local displacement increment of the anchor plate is based on the incremental iterative method to simulate the whole process trajectory of VLAs towed embedded soil for installation and mooring loading work to the final recycling and utilization,and analyzes the change of anchor plate and anchor state during the whole process.The regularity,the trajectory of the centroid position of the anchor plate and the law of the development and change of the pullout resistance performance.The centrifugal model test was then carried out at 100 g to simulate the entire process of VLA installation and loading and was compared with numerical calculations.On the basis of this research and analysis,detailed parametric research work was carried out to study the effects of the following factors on the ultimate depth and pullout resistance of VLAs during installation and mooring loading:(1)The bridle shank parameters of VLAs,(2)the angle between the anchor chain and the horizontal direction at the surface of the seabed during installation and loading,(3)anchor chain load parameters,(4)friction coefficient between anchor chain and soil,(5)yield surface parameters and(6)anchor weight parameters.When the bridle ratio is 0.8,after the loading process starts,the anchor plate rapidly rotates clockwise by about 14° to reach the approximate normal force state.In this process,the anchor plate depth loss is 0.26 m,which is only 0.19% of the ultimate buried depth.During the initial rotation of the anchor plate,the pullout force increased rapidly,and the anchorage force at the mooring point and the surface of the seabed increased by 43.66% and 35.48%,respectively.It can be seen that the pullout resistance is not only related to the buried depth of the anchor plate.The state relationship between the anchor plate,the anchor and the anchor chain is highly correlated.Through the centrifugal model test,the installation and loading process of the normal bearing anchor with the anchor ratio of 0.7-1.0 is simulated.The comparison between the model test results and the numerical calculation results shows that the comparison results show good consistency.During the installation process,with the increase of the anchor ratio,the anchor plate has an increasing depth of the anchor plate at the same towing installation distance.During the loading process,the bearing capacity coefficient shows a tendency to increase first and then stabilize.The results of the numerical calculations are consistent.In the parametric research process,the influence of different parameters on the depth and pullout performance of VLAs showed different trends.The results show that the anchorage has a significant influence on the anchorage morphology under the limit of buried depth,which further significantly affects the ultimate depth and pullout force of the anchor plate,thus directly affecting the ratio of depth performance to bearing capacity.influences.However,due to the different requirements in practical applications,the optimal value of the anchor ratio is different,so the design should be based on actual needs to make a trade-off to finalize.In addition,for high-limit embedding depth and pull-out resistance,anchor chains with high friction coefficient and low load-bearing parameters should be used.On the other hand,for all the parameters discussed in this paper,the use of smaller mudline anchor angles and relatively thin anchor plates allows VLAs to better perform their load bearing properties.Overall,the research shows the potential direction of improving the VLAs,and helps to understand the mechanism of the VLAs in research and practice.