プラスチックボルトの引張衝撃試験法に関する研究

試験機の試作と特性の評価方法について

抄録

In this paper, a method for evaluating the strength of plastics bolt under tensile impact load is considered, for the purpose of obtaining available data for the strength design of the bolted joint with the plastics bolt. First, a testing machine, which enables to measure the tensile load acting on the bolt and the energy absorbed into it during tensile impact whether the bolt is broken or not, is built as a trial because it is impossible to evaluate these values by means of the standardized testing methods. Second, by means of this machine, the characteristic values for generalizing the strength of the bolt under impact load are considered varying the nominal diameter of the bolt, fastened length of the bolted joint and impact energy. As the result, obtained conclusions are as follows: (1) The maximum tensile load induced to the bolt by impact can be generalized by use of the impact energy per unit volume of the bolt and the maximum tensile stress, in spite of the nominal diameters of the bolt and fastened lengths of bolted joints. (2) The energy absorbed into the bolt can be also generalized by use of both the impact energy and the absorbed energy per unit volume of the bolt as far as the necking is not occurred in the bolt.