| The pipe-soil interaction of steel catenary riser is closely related to system safety.In this paper,a model of local pipe-soil interaction in contact area is established,which is by combining soil strength change with CEL method through ABAQUS user-defined subroutine.Compared with previous studies,the reliability of the model is verified,and the pipe-soil interaction is simulated by changing the loading mode.The soil resistance and trench development are studied,and the sensitivity of various factors is analyzed.In the case of vertical displacement of pipe,the loading mode is determined as displacement control,and the loading form of analysis step is linear.After adjusting the model,the sensitivity of non-soil related factors such as loading mode,pipe penetration depth,velocity and contact friction are studied.The soil deformation and resistance changes during pipe penetration are analyzed.In addition,the sensitivity of soil related factors such as shear strength and soil remolding parameters are analyzed.The stress distribution of soil deformation is studied and the influence of different factors on soil strength is determined.The pipe-soil interaction is studied when the pipe moves horizontally.The sensitivity analysis of initial buried depth,soil strength,soil remolding parameters and pipe transverse velocity is carried out under the limitation of vertical displacement.The influence relationship between soil resistance and related factors is obtained.Under the condition that vertical displacement is not limited,that is,vertical force loading,the effect of pipe self-sinking and friction coefficient are studied.According to the coupling case of horizontal and vertical displacement,the influence of oblique penetration angle of pipe on soil resistance was studied.The change rule of horizontal and vertical resistance was obtained,and a simple approximate yield envelope calculation method was proposed.In horizontal and vertical cyclic displacement of the pipe,the soil resistance changes caused by cyclic number and external load are studied. |
