To analyze the reliability of the multi-circle ground motion attenuation model

of which the rationality has been demonstrated by the ground motion attenuation relation analysis of the Wenchuan earthquake

the measure of dividing fault and getting sub-source epicentral distance were studied based on NGA database. The multi-circle ground motion attenuation relationship of NGA database was fitted

and the types of fault

hanging/foot wall and coverage thickness on fitting ground motions were discussed respectively. The fitting results of multi-circle model have been compared with that of NGA model (BA08)

and the difference between the two results was analyzed. The results show that the multi-circle model gives a good fitting result for spatial distribution of ground motion of NGA database. Due to the simple form and high precision

the multi-circle model with specific theoretical basis would have further development through this project.