Abstract:

The distribution and characteristics of liquefaction-induced damages during Wenchuan Ms8.0 Earthquake in China were summarized in detail according to the wide and detailed field investigation. The analytical results are as follows. (1) The liquefaction phenomena are evident, involving thousands of Hundreds thousands square meter of farmland. (2) The liquefied sites distribution and the liquefaction-induced damage distribution are correlated but not the same. Comparison of the liquefaction phenomena, the 3 liquefaction-induced damage areas in Deyang are the most serious; Dujiangyan, Mianyang and Jiangyou districts are the secondly serious; and other areas are relatively light. (3) In the liquefied sites, the poor houses without any consideration of seismic resistant design collapsed, even the houses/buildings with collar beams and constructional columns subsided or tilted. (4) The liquefaction phenomena are typically severe in schools, generating ground fissures and causing buildings tilting, subsiding and cracking. Three obvious characteristics of the liquefaction-induced damage are: (i.) The liquefaction aggravates the structural damage and no shock absorption phenomenon has been observed. (ii.) In the regions of seismic intensity of VI (PGA less than 0.05g), liquefaction phenomena and liquefaction-induced damage were observed and quite remarkable. (iii.) The liquefaction generated ground fissures are the significant cause of liquefaction-induced damage.

Key words: Wenchuan earthquake, liquefaction, damage, distribution, characteristics