Use of the FMVSS-214 static bending test to evaluate an automobile side door impact beam made of glass fiber-reinforced plastic

A side door impact beam absorbs energy and plays an important role in preventing intrusion of another vehicle into the occupant area. Impact beams are being actively researched to reduce vehicle weight while still meeting the strength requirements of environmental regulations and to improve fuel efficiency and enhance safety. No study has subjected a lightweight glass fiber-reinforced plastic (GFRP) impact beam to the Body in White (BIW) Federal Motor Vehicle Safety Standard (FMVSS)-214 quasi-static test. We compared three beams that differed in shape and stacking pattern. We performed three-point bending analyses, bending tests (including after bracket tightening), and static bending tests of door assemblies. The best GFRP beam (B) and a steel model were compared in terms of BIW static bending performance. The front-door GFRP beam exhibited an average reaction force 135% of that mandated by the FMVSS-214S test specification, an intermediate average reaction force 158% of that required, and a final force 154% of that required. In terms of bending performance, the initial average reaction force was 9.5% higher than that of the steel impact beam, and the rear door force was 6.6% lower. The reaction force of the GFRP beam decreased rapidly as breakage occurred after bending through 110.0–120.0 mm; however, the average reaction force was similar to that of the steel beam. Thus, the GFRP impact beam met the legal requirements but weighed 30% less than the steel beam.