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The main objective of the paper is to investigate the dynamic response of the prestressed beams on rigid supports to moving concentrated loads. The governing equation of the transverse vibration of a prestressed continuous beam under the ununiformly distributed load is analytically formulated, taking into account the effect of the prestressing. The forced transverse vibration of the beam under the action of a large number of moving bodies has been investigated by using the method of substructures. In addition, the reaction forces at every rigid supports can be determined from the obtained differential equations. A comparison between the numerical results for the prestressed and the non-prestressed beam is presented to show the influence of the prestressing and the moving velocity of the bodies on the dynamic response of the beam. The calculating results are also examined and validated by experimental measurements at a large ferroconcrete bridge in Vietnam.

This paper deals with the problem of inverse kinematics and dynamics of a measuring manipulator with kinematic redundancy which was designed and manufactured at Hanoi University of Technology for measuring the geometric tolerance of surfaces of machining components. A comparison between the calculation result and the experimental measurement is also presented.

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The main objective of the present paper is to study the transverse vibration of the prestressed beams. The differential equation of the transverse vibration of the Euler-Bernoulli beam is developed, in which the initial axial strain in every cross section of the beam is taken into account, so that the initial normal stress is not equal to zero. We have proposed some formulae to determine the natural frequencies of the prestressed beam. The forced transverse vibration of the beam with a moving external force has been considered. From this it follows compression softening effect of prestressed beams. A detailed comparison between the calculating results for the prestressed and the non-prestressed beam is also presented.