Empirical models for predicting protective properties of concrete shields against high-speed impact

We have accumulated practically all the information available in the literature regarding empirical models used for describing high-speed normal penetration of rigid strikers into concrete shields, including recently posed models. The description of the models is unified; this includes recommendations on the range of applicability of the models and additional restrictions implied by the used mathematical formulations. The description of the models is quite comprehensive, and allows their direct application. All the relevant formulas are presented in SI units. In addition to this extensive survey we include the results of original comparative investigations on the performance of various models for describing penetration into semiinfinite and finite-thickness shields. Nomenclature b Thickness of the shield b perf Perforation thickness b scab Scabbing thickness BLV Ballistic limit velocity c Maximum aggregate size of concrete c Half-size of the concrete aggregate CRH Caliber radius head of a ogive-nosed projectile d Maximum diameter of impactor, reference size DOP Depth of penetration Parameter, (24) E Young's modulus of material of projectile E steel Young's modulus of steel f c Unconfined compressive strength (Pa) H Depth of penetration H (i) min ,H (i) max Parameters in functions perf (H ) and scab (H ), (A.1) H (i) * Parameter, (A.4) H exp DOP obtained in experiment