工字型钢护栏碰撞安全性能仿真研究

Simulation Study on Safety Performance of I-shaped Steel Barriers in Collision

工字型钢护栏广泛应用于我国钢结构桥梁中,调查研究发现大部分护栏阻挡能力满足要求,但其缓冲性能有待提升。因此,本文提出了一种可以应用于工字型钢护栏的O形防阻块,该防阻块可将立柱与横梁间的硬接触调节为弱接触,从而提升护栏的缓冲性能。本文将防阻块加入到工字型钢护栏中,在Hypermesh中建立货车-护栏耦合模型,研究中考虑将防阻块分4种壁厚进行对比分析。使用LS-DYNA进行碰撞仿真研究,依据公路护栏安全性能评价标准,从护栏的阻挡、缓冲、导向功能三个方面对护栏安全性能进行分析,研究发现防阻块壁厚应在4~10 mm间,6 mm为宜。本文研究结果表明工字型钢护栏使用合适壁厚的防阻块后,护栏满足防护要求,且护栏的耗能能力、缓冲性能显著提升。

I-shaped steel barriers are widely used in steel structure bridges in China. Investigation and research have found that most of the barriers have sufficient blocking capacity, but their buffering performance needs to be improved. Therefore, this paper proposes an O-shaped block which can be applied to I-shaped steel barrier, and adjust the hard contact between the column and the beam into weak contact, so as to improve the buffer capacity of the barriers.In this paper, the blocks are added to the I-shaped steel barriers, and the van-barrier coupling models are established in HyperMesh. In this study, the blocks are considered to be divided into 4 wall thicknesses for comparative analysis.LS-DYNA is used for collision simulation research.According to the standard for safety performance evaluation of highway barriers, the safety performance of the barrier is analyzed from the three aspects of its containment, buffering and redirection performance.The study found that the wall thickness of the block should be between 4 and 10 mm, preferably 6 mm.The results show that the I-shaped steel barriers can meet the protection requirements, and the energy dissipation performance and buffering performance of the barriers are significantly improved after using the blocks with appropriate wall thickness.