The Indoor Model Test And Numerical Simulation Research Of Gravity Anchor

Humans began to exploit the ocean actively since the 1950 s,Different kinds of ocean engineering arises all over the world,Developing Marine needs various Marine mooring system(such as ocean carrier、drilling platform、oil storage ship),All kinds of anchor used in ocean engineering arises at that moment.Gravity anchor consists of concrete block or steel block,broken metal or other high-density materials.Gravity anchor,an ancient form of anchor,depends on its self-weight and the interaction between subsoil and the anchor to provide anchoring force.The capacity of bearing horizontal load is the function of friction between the anchor and the seafloor sediment and the shear strength of seabed sediment.Based on the indoor model test and combined with the finite element software,the horizontal loading process of gravity anchor on calcareous soil and clay have been simulated.First,in the process of the development of the south China sea,people may find many Marine soil engineering problems,Than Several anchor foundations are introduced,than describe the distribution of calcareous soil of the south China sea,and the research progress of domestic and foreign scholars on the Marine soil.Second,Describes the indoor model test and related principles,According to the indoor model test,Pulling force-time curve and the movement process of different forms of gravity anchor in calcareous soils were made,Focusing on the Flat gravity anchor and 8keys gravity anchor movement process under different soil conditions.Different soil conditions show different mode of failure: graduate failure and abrupt failure.For graduate failure,the failure surface is located in the soil,but for abrupt failure,failure surface is located between the bottom of anchor and rock.Because of bigger risks,abrupt failure need to pay more attention in the process of design and calculation.ABAQUS is widely used in engineering and the basic operation procedure is mainly introduced,the advantages(disadvantages)and applicable scope about ABAQUS/Standard and ABAQUS/Explicit was compared.Than introduced several common unit type and relevant theories about contact analysis.It provides a theoretical basis for Model Building and post-processing analysis.Than process of numerical calculation model and attention are described in detail.After that the results of numerical simulation and indoor model test are compared,gravity anchor show different motion modes on Calcareous sand and calcareous rock.The existing design method of gravity anchor is applicable for abrupt failure mode.While the graduate failure will be safer.At last,a kind of gravity anchor used on the clay is introduced by indoor model test.Different loading angles have been taken into account and simulated.The experimental results showed that the bearing capacity of lattice gravity anchor reach the maximum.and the failure mode of the gravity anchor on the clay under different loading angles are all pulled out.