Aiming at the safety risks of mooring line breakage and excessive vessel motions induced by eccentric berthing due to the dense layout of loading arms at oil and gas chemical terminals,this study takes a specific oil and gas chemical terminal in Ningbo as an engineering case to conduct an eccentric berthing response analysis.Based on the OPTIMOOR mooring analysis software,simulations are carried out for ship types of 150,000,50,000,and 5,000 DWT under the working conditions of full load at design low water level and ballast at design high water level,so as to examine the response laws of mooring line forces and vessel motion quantity at different eccentric berthing positions.The results show that the mooring line forces of the three ship types are all lower than the design breaking strength,the longitudinal displacement increases significantly when the vessel drifts to the right.Specifically,the 150,000 DWT vessel in ballast condition exceeds the limit at a right drift distance of 10.5 m,the 50,000 DWT vessel exceeds the limit when its right drift distance exceeds 8.4 m in full load condition and 4.2 m in ballast condition,and the 5,000 DWT vessel in full load condition at 2#-4 berth reaches the critical state at a right drift distance of 3.75 m.All transverse displacements are within the 2.0 m limit.The study indicates that ship dimensions and drift distance are the key factors leading to the attenuation of mooring restraint effects.On this basis,measures such as adjusting mooring bollard positions and optimizing mooring line configurations are proposed to enhance longitudinal restraint capacity,which can provide theoretical basis and technical reference for the design of similar terminals.