Dynamic compression experimental method of Hopkinson pressure bar

Abstract

The invention discloses a dynamic compression experimental method of a Hopkinson pressure bar. The invention has the advantages that the experimental data testing and analyzing method of the traditional Hopkinson technology can be conveniently adopted and the validity of the experimental result can be ensured in a macro sense, thereby meeting the requirements of a heterogeneous material test specimen, such as concretes with large size and the like, on dynamic compression experimental study; since each horizontal bar is provided with a foil gauge in a sticking manner for testing the stain waveon the horizontal bar, so that the damage evolution and local damage features of different part of the test specimen can be reflected through reflected wave and transmitted wave in each pair of the horizontal bars, and the crack evolution features of the heterogeneous material test specimen, such as concrete and the like, can be probed in the impact process by back analysis of the stress wave, thereby acquiring more abundant information about the damage process of materials.

Description

technical field [0001] The invention relates to an experimental method of mechanical properties of materials, in particular to a dynamic compression experimental method of a Hopkinson compression bar. Background technique [0002] The study of dynamic constitutive properties of heterogeneous, multiphase brittle materials such as concrete, rock, foam and engineering ceramic composites, taking into account the mesostructure and damage evolution, has become the common focus of the current mechanics, materials science and engineering circles. Interdisciplinary cutting-edge research hotspots. Represented by the most widely used concrete in the engineering field, modern concrete structures should increasingly be considered to withstand violently changing impact loads, such as: various protective structures, nuclear reactor vessel shells, marine engineering structures and bridges, etc., are under attack by weapons When impact loads such as , explosion, earthquake, and sea waves, e...

AI Technical Summary

Problems solved by technology

However, the Hopkinson dynamic experimental method must meet the two basic assumptions of "one-dimensional stress wave" and "uniform distribution of stress and strain along the length of the specimen". If the diameter of the Hopkinson compression bar is simply increased, the "one-dimensional stress wave" will be destroyed. The basic assumption of "stress wave" brings a significant lateral inertia effect, which directly affects the validity of the experimental results. Therefore, the conventional Hopkinson compression bar technology and method cannot meet the experimental research on the dynamic compression properties of heterogeneous materials such as engineering concrete.

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