TIME DEPENDENT VARIATION OF THE DEFORMATION OF A STRIP WITH CIRCULAR HOLE UNDER CONSTANT COMPRESSIVE LOAD

抄録

In the present paper, the deformation and stress state and their time dependent variation of a strip with circular hole of an elastic-viscoplastic material are investigated experimentally by using the photorheological method in the period from the instant of application of a constant compressive load to the static equilibrium state under the same load. As the result, it is made clear that the effect of viscosity of the material in the transient period is remarkable, and thus the deformation and stress state in the equilibrium state are quite different from those at the instant of loading. Deformation of the hole is measured in relation to time, which shows that the deformation during the transient period is far larger than that at the instant of loading. Moreover, the stress distribution in the minimum cross section of the strip and its time dependent variation are discussed in detail comparing with the existing data obtained by elastic theory or photoelasticity.