Soilbags have been understood to be cheap and easy to acquire as well as vibration reduction. However

the research on the effect of soilbag vibration reduction is only based on test results at present; the mechanism of it has rarely been studied. Based on the principle of soilbag energy dissipation

the discrete element method is used to build energy dissipation equation during the process of soilbag vibration reduction. Firstly

using the discrete element method to establish every part of soilbag energy dissipation equations

through numerical simulation of a single soilbag under simple vertical loading condition

from energy conservation perspective to verify that the calculation of each part of the energy is reasonable; meanwhile

the correctness of the established equations of energy dissipation is proved; and then energy dissipation of a single soilbag is simulated from quantitative perspective by using the verified energy dissipation equation under the cyclic loading rate of 1 000 N/s three times. The numerical simulation results show that the percentage of total soilbag and its inside particles energy consumption exhibit obvious wavy shaped fluctuating with loading and unloading; the percentage of it is over 75% of the total energy; this means soilbag can play a good effect on energy dissipation.