Study On Motions Of Ship Moored Floats Which Are Broken In Regular Waves

Floating causeway pier system is such a floating structure that is built on the inshore waters,and can be used for the barges and the small transport vessles to berth and operate.In adverse sea conditions,the system can be disassembled to several floating bodys and survive with mooring,and the floating bodys are easily to be broken because of the collision between each other,so the study of the motion response of the floating causeway pier system and the standard causeway unit in the case of moored and broken becomes an urgent issue to be solved in the current.This paper mainly research on the motion response of ship moored float,such as the motion response of standard causeway unit in the case of moored and broken,and we try to find a more accurate and practical ways to solve these issues.As the motion of moored float is closely associated with non-linear theory,which can not be accurately solved by the linear theory.So it is necessary to develop a method which can include these non-linear factors.In this paper, the author take the non-linear and time-domain method,considering the slightness charactristics of the standard causeway unit,use two-dimentional distribution of sources method to get the entire hydrodynamic coefficient and wave force,use adding weight method to deal with the affect of water coming to the moored float when it is broken,take the single-point mooring system as a spring with linear restoring stiffness,establish the equations of motion response of the broken moored float which is acted by the non-linear regular wave,and work out the programmes to calculate the motion response of the standard causeway unit in time-domain,which is based on the Fourth-order Runge-Kutta method.The mechanical model and numerical simulation programmes are applicable to calcute the motion response of the slender float such as the ship moored float.In this paper,the auther take the standard causeway unit as an example to analyse the the motion response of the unit when it is in integrity or damaged condition,and analyse the differences between these two conditions.