The study of sand liquefaction issues

especially in sand liquefaction evaluation

has made significant progress

and its fruits are widely used in the real engineering project or adopted in the seismic code

while the liquefaction potential of gravels is still unclear.The gravels were usually regarded as non-liquefiable soils because of large grain sizes and generally high permeabilities in the past.Field investigation and test of gravels liquefaction sites following the 2008 Wenchuan earthquake

and comparison of gravels liquefied cases history from previous earthquakes

reveal that:（1） Limited gravels liquefaction cases history from previous earthquakes warn that loose to moderate density of gravels have much potential to liquefy under a given earthquake shaking.The widespread gravels liquefaction following the 2008 Wenchuan earthquake reveal it is not reasonable to regard gravels as non-liquefiable soils without any treatment;（2） The grain size distribution curves from the Wenchuan earthquake cover a wider range of grain sizes than those reported from previous earthquakes

indicating that gravels characteristics liquefied in the Wenchuan earthquake are representative and universal.The gravels liquefaction evaluation method developed from the Wenchuan earthquake should be feasible for worldwide use.