research into dynamic wheel loads applied to roads by vehicles passing over surface irregularities is reviewed. it is shown that dynamic wheel loads can be as much as twice static wheel loads (measured on ordinary stretches of highway), and as the ability of a wheel to damage a road structure is very dependent on the wheel load, it is desirable to minimise the dynamic component of wheel load by suitable modifications to suspension design. tyre stiffness and shock absorber damping are shown to be the suspension parameters with the most influence on dynamic loads, they decrease as tyre stiffness is decreased, and an optimum value of damping exists for a simple shock absorber that minimises dynamic loads. there is conflicting evidence on the dynamic loads produced by tandem-axle suspensions. experimental work indicates that they cause less damage than equally loaded single axles, but there is other evidence that they are less well damped and can generate higher subgrade stresses. the report identifies the further research needed to enable improved suspension systems to be designed. (a)

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