Response of containment vessels to explosive blast loading

The response of steel containment vessels to the blast loading produced by the detonation of high explosives is investigated by experiments, computations, and analysis. The vessels are thin-wall shell structures that are nearly spherical. All explosive charges are solid spheres, centrally initiated and centrally positioned within the vessels. Most of the work concerns vessels that contain, in addition to the explosive charge, air at ambient or reduced pressures. One-dimensional, Lagrangian, finite-difference calculations are used to study the blast phenomenon and the details of the loading pulse applied to the vessel wall. The results are verified by comparisons with pressure gauge records. In addition, vessel response to the pressure loading is calculated by both finite-difference and finite-element computer codes. The two-dimensional motion, which occurs after significant wave interactions have taken place in the test vessels, can be simulated, with reasonable accuracy, by finite-element calculations. This result indicates that a predictive technique and, therefore, a design tool appear to be available with these standard calculational methods

Improved technique for determining dynamic material properties using the expanding ring

Since its introduction nearly two decades ago, the expanding ring test has shown considerable promise as a simple method of obtaining strain-rate-sensitive uniaxial material property data. The procedure is to monitor the kinematics of a uniformly expanding ring. The stress-strain-strain rate response of the ring material can then be calculated from the ring equation of motion and the recorded data. Efforts in the past have been based upon recording the transient displacement of the ring. Determination of the stress in the ring then required double differentiation with respect to time of the ring displacement. The work reported herein is an attempt to overcome this difficulty by directly measuring ring velocity as a function of time by means of a laser velocity interferometer; this method requires one less differentiation of the data. The procedure is illustrated by experiments performed on annealed and hardened copper rings. Results are compared to quasi-static material properties determined for the same materials using conventional techniques

Development of the freely expanding ring test for measuring dynamic material properties

Modifications to the freely expanding ring test for eliminating adverse two-dimensional effects are described and illustrated. The result is to substantially increase the strain-rate range over which dynamic material property data can be reliably obtained. Several different ring launching schemes are discussed, and data are presented that were taken with a particular shockless electromagnetic system. Results from initial attempts at measuring dynamic compressive properties with a contracting ring are presented

Dynamic response of containment vessels to blast loading

The dynamic response of steel, spherical containment vessels loaded by internal explosive blast was studied by experiments, computations, and analysis. Instrumentation used in the experiments consisted of strain and pressure gauges and a velocity interferometer. Data were used to rank the blast wave mitigating properties of several filler materials and to develop a scaling law relating strain, filler material, and explosive energy or explosive mass

Lithium as a Differential Neuroprotector During Brain Irradiation

info:eu-repo/semantics/publishe