An analytical solution for wave propagation in conical bars applicable to the measurement of the dynamic tensile strength of solid materials
DOI:
https://doi.org/10.14195/2184-8394_100_8Keywords:
Dynamic tensile strength, Laboratory testing, Elastic wavesAbstract
A study on the propagation of elastic stress waves in conical bars of finite length is presented, for the purpose of developing an analytical solution to the stress states created when a certain impact is applied to the base of the cone, traveling towards its apex. The method is based on the superposition of longitudinal waves propagating along the bar cylindrical core and reflected waves (longitudinal and transverse) which are created near the lateral surface of the cone, in order to allow the determination of the state of stress at any circular section inside the bar.
It was detected that such a superposition generate tensile stresses that may lead to failure by means of conical fragments, whose dimensions are useful for the measurement of the dynamic tensile strength of the material forming the bar. Application examples of the method in lab tests are provided.
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