A unified and rigorous solution for quasi-static cylindrical cavity expansion in plasticity constitutive models

In this article, we investigate the results obtained using different constitutive models for the solution of the cylindrical cavity expansion problem under plane strain conditions. The cylindrical cavity expansion solutions are employed with the cylindrical cavity expansion approximation to obtain ballistic limit and residual velocities for ductile metals perforated by rigid projectiles. Many of the previously developed cylindrical cavity expansion approximations use simplified constitutive models. However, in the present work, we first extend the cylindrical cavity expansion theory with the Voce strain hardening rule, before we utilize three different strain hardening constitutive models in cylindrical cavity expansion calculations to predict ballistic limit and residual velocities of aluminum and steel target plates struck by rigid projectiles. The results show that when strain hardening is accurately represented by the constitutive models until necking in a uniaxial tension test, all cylindrical cavity expansion models predict ballistic limit velocities that are close to the experimental data.

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Dynamic finite cylindrical cavity-expansion models for cellular steel tube confined concrete targets normally impacted by rigid sharp-nosed projectiles

International Journal of Protective Structures ◽

10.1177/20414196211027288 ◽

2021 ◽

pp. 204141962110272

Author(s):

Chaomei Meng ◽

Dianyi Song ◽

Qinghua Tan ◽

Zhigang Jiang ◽

Liangcai Cai ◽

...

Keyword(s):

Cylindrical Cavity ◽

Approximate Model ◽

Steel Tube ◽

Confinement Effect ◽

Confined Concrete ◽

Cavity Expansion ◽

Depth Of Penetration ◽

Cylindrical Cavity Expansion ◽

Infinite Cylindrical Shell ◽

Response Modes

Cellular steel-tube-confined concrete (CSTCC) targets show improved anti-penetration performance over single-cell STCC targets due to the confinement effect of surrounding cells on the impacted cell. Dynamic finite cylindrical cavity-expansion (FCCE) models including radial confinement effect were developed to predict the depth of penetration (DOP) for CSTCC targets normally penetrated by rigid sharp-nosed projectiles, and stiffness of radial confinement was achieved with the elastic solution of infinite cylindrical shell in Winkler medium. Steady responses of dynamic FCCE models were obtained on the assumption of incompressibility of concrete, failure of comminuted zone with Heok–Brown criterion and two possible response modes of the confined concrete in the impacted cell. Furthermore, a DOP model for CSTCC targets normally impacted by rigid projectiles was also proposed on the basis of the dynamic FCCE approximate model. Lastly, relevant penetration tests of CSTCC targets normally penetrated by 12.7 mm armor piecing projectile (APP) were taken as examples to validate the dynamic FCCE models and the corresponding DOP model. The results show that the DOP results based on dynamic FCCE model agree well with those of the CSTCC targets normally penetrated by rigid conical or other sharp-nosed projectiles.

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