After the occurrence of a destructive earthquake

according to building and structure damage characteristics

it is important and imperative to revise the current seismic design codes.Combining with the seismic damage investigation in Wenchuan earthquake

this paper analyzes the seismic earth pressure of crushed gravel filled gravity retaining wall（GRW）and distribution of earth pressure by using large-scale shaking table model test.Based on the above analysis

reasonable discussion and refinement are made on current seismic design codes of railway and highway.The following conclusions are drawn.First the earth pressure on the GRW shows a single peak curve distribution along the wall and 60%～80%acting on the central.Second

with the increase of peak ground acceleration

the seismic earth pressure distribution gradually deviates from the triangular linear distribution.The acting point of resultant force is higher than 1/3 of the wall high

in fact

nearly 0.4 times the wall high under the action of seismic acceleration.On rock site with coarse wall back fill

it is suggested that the acting height of seismic earth pressure takes 0.35 times the wall height.Finally

comparative calculations show that current seismic design specifications can basically meet the project requirements

but it is suggested to make the necessary provisions about seismic design of flexible retaining walls.