Riprap protection of embankment is most widely applied in the middle and lower Yangtze River which can increase the flood control capacity of embankment and safeguard the flood safety of plains and major cities along the Yangtze River.However,rubbles crept down frequently that can lead to the damage of revetment.In order to comprehend the failure mechanism,flume experiments were carried out under different conditions such as different slope gradient,different particle size of rubbles,and different velocity.The damage of riprap revetment was researched from the characteristics of rubble force,flow characteristics,rubble displacement and rubble collapse.And then,the discriminant index of the degree of damage and the time node for maintenance was put forward.