Abstract:Dump truck has load heavy and poor working conditions,which needs a suspension with simple structure and good cushioning effect.The hydro-pneumatic suspension meet the above requirements is widely used.According to the structural characteristics of single chamber hydro-pneumatic suspension,the output characteristics mathematical model was built.According to the mathematical model,the simulation model was built based on AMESim,and the test rig of the suspension was set up.The characteristics of slow loading experiments and periodic excitation loading experiments were compared and analyzed,and the model parameters were corrected.The results show that the effect of friction force cannot be neglected when the difference between load and friction force is smal,the static stroke has obvious change compared with the initial design stroke;as the temperature increasing,the output force of the whole tension decreases;when the stroke is relatively large,due to the impact of pressure and piston rod agitation,the oil will dissolve part of the gas,will lead to the decline of the overall elastic modulus of oil,and the effect to the output is obvious;the flow coefficient is corrected;it is in line with the actual situationoil when the compressible elastic modulus value is 1 000 MPa and the flow coefficient is 0.90~0.92.