This paper describes the results of primary response measurementscarried out to study the effects of dynamic loadings of vehicleson pavements. The measurements were made at the Virttaa test sitein Finland as part of the OECD/DIVINE project. Two instrumentedpavements and two artificial bumps were used to excite body bounceand axle hop. Instrumented vehicles were from Canada, the UnitedKingdom and Finland. The strains at the bottom of the bituminouscourses were in almost direct proportion to the dynamic wheelloads on thick bituminous pavement. They were similar if therewere air or steel suspensions or if the dynamic load was causedby body bounce or axle hop. On thin bituminous pavement the sizeof the changing tire imprint plays an important role and dynamicwheel loads have only a slight effect on the strains.