3D finite element simulations of high velocity projectile impact

Abstract

Abstract. An explicit three-dimensional (3D) finite element (FE) code is developed for the simulation of high velocity impact and fragmentation events. The rate sensitive microplane material model, which accounts for large deformations and rate effects, is used as a constitutive law. In the code large deformation frictional contact is treated by forward incremental Lagrange multiplier method. To handle highly distorted and damaged elements the approach based on the element deletion is employed. The code is then used in 3D FE simulations of high velocity projectile impact. The results of the numerical simulations are evaluated and compared with experimental results. It is shown that it realistically predicts failure mode and exit velocities for different geometries of plain concrete slab. Moreover, the importance of some relevant parameters, such as contact friction, rate sensitivity, bulk viscosity and deletion criteria are addressed.

On the dynamic response of reinforced concrete beams subjected to drop weight impact

“…However, for structures subjected to very high strain rates (>10 s -1 ), e.g. high-speed projectiles impact on concrete slabs, it has in [53] been shown that the bulk viscosity can have a significant influence on the resulting projectile penetration depth. There, it is also argued that bulk viscosity, due to both physical aspects and numerical reasons, must be included in the analysis.…”

Impact Analysis of Thermally Pre-Damaged Reinforced Concrete Frames

“…The influence of loading rate on the behavior of quasi-brittle materials and structures has been intensively studied and better understood in recent years [ 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 ]. It is well known that the resistance, failure mode, crack pattern and crack velocity in concrete are strongly influenced by the loading rate.…”

“…It is well known that the resistance, failure mode, crack pattern and crack velocity in concrete are strongly influenced by the loading rate. The rate dependent response of concrete is controlled through three different effects: (i) through the rate dependency of the growing micro-cracks (inertia effects at the micro material level); (ii) through the viscous behavior of the bulk material between the cracks (viscosity due to the water content) and (iii) through the influence of inertia on a meso and macro scale, which comes from different sources [ 27 , 28 , 29 , 30 , 31 ]. In numerical studies (meso- or macro-scale), the first two effects should be accounted for through the constitutive law and, assuming that the resolution of structural discretization is fine enough, the third effect should be automatically accounted for through dynamic analysis.…”

“…For concrete, which is quasi-brittle material, the first two effects dominate for medium and high loading rates. The influence of inertia dominates in the case of higher loading rates (impact), however, even then the material rate dependency cannot be neglected [ 31 ]. Different aspects of inertia need to be distinguished: structural inertia, present even in case of elastic analysis, inertia due to the softening or hardening of material exposed to fast loading rates, and inertia at the crack tip, which is responsible for crack branching phenomena.…”

Dynamic Fracture of L and CT Concrete Specimens: Numerical and Experimental Studies

“…For quasi-brittle materials, such as concrete, the first two effects are important for relatively low and medium strain rates. For higher strain rates (impact) the influence of inertia dominates, however, the rate dependency cannot be neglected [13].…”