サンドイッチ構造をもつＦＲＣの衝撃曲げ挙動に及ぼす強化材の影響

Abstract

The bending behavior under impact load was studied for the sandwich beam consisting of FRC (fiber reinforced cement) to give a guide for its effective use. As representative examples of FRC signifying different characteristics, GFRC (glass fiber reinforced cement) and NFRC (nylon fiber reinforced cement) were selected.In the experiments, the impact test was carried out with a three-point bending method by using a falling elastic bar. And the strain caused by the transient phenomenon in the loading elastic bar and the location where the crack occurred in the FRC were measured. Then the impact resistance of FRC was considered.Moreover, in order to interpret the behavior of the sandwich beam under impact load, a simple sandwich model with a homogeneous reinforcement was constructed for analyzing the impact test and for facilitating numerical calculation. And the effect of the span length on the dynamic flexural strain of the sandwich beam was considered.From the results obtained experimentally and numerically, it was shown that the crack occurred at the same position of the specimens, independent of the span length, and that the impact resistance of FRC improved by using it as a sandwich construction.