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The great 2008 Wenchuan Earthquake in Sichuan,China caused unprecedented loss of human life and wide spread severe damage to many types of structures.This event had a moment magnitude of 7.9 and 3 near-source records were obtained within a source distance of 20km.Large permanent ground displacements possibly due to fault rupture have been reported along the Longmenshan fault and a secondary fault.The largest horizontal permanent ground displacement is 5.3m and the largest vertical displacement is 6.2m.Such a large permanent ground displacement usually generates a large velocity pulse (fault-fling pulse).Among the 3 near-source strong-motion records,the Mian Zu Qing Ping ( MZQ ) record appears to have a large fault-fling pulse in the fault-normal direction and the Shi Fang Bajiao (SFB) record appears to have a large fault-fling pulse in the vertical direction.The permanent ground displacements in the other directions cannot be reliably estimated.The relatively large response spectra over 2s spectral period in the fault-normal component of the MZQ record are likely to be caused by fault-fling effect.The vertical response spectra of the SFB record in the period range of 0.2- 0.9s are comparable with or larger than those of the horizontal components,a possible result of vertical fault-fling effect.The displacement time-histories and response spectra of the two near-source records are compared with those of the TCU052 and TCU068 records from the 1999 Chichi,Taiwan earthquake.The fault-fling effect is likely to be one of the causes of severe damage and collapse of many structures within a short distance from the fault surface rupture.The duration of large accelerations in both MZQ and SFB records is much higher than those of the near-source records with very large permanent ground displacement from the 1999 Chichi,Taiwan earthquake.These accelerations lead to a high damage potential for damage to short-period structures in areas close to these two recording stations.