The steel–concrete composite beam, consisting of a concrete slab, a steel beam, and shear connectors, is extensively utilized in bridge engineering due to its effective utilization of material properties and convenient construction. Considering the significant impact of explosive incidents on bridge safety, and the limited experimental research on blast performance of composite beams, this study tested three small-scale SC composite beams arranged with commonly used shear connectors, including studs, PBL ribs, and combination connectors, under contact explosion with 200 g of TNT. Finite element (FE) models, validated by the experimental data, were established to conduct damage analysis to understand the damage mode and characteristics of SC composite beams. The results showed that the SC composite beams exhibit a localized damage pattern concentrated in the mid-span of the beams under contact explosions. The concrete spalling on the bottom surfaces could be divided into two parts by the top flange of the steel beam. The concrete slab, which absorbs more than 94 % of the total internal energy of the SC composite beams, plays the most important role in reducing the damage to the beams under contact explosion. In some aspects, the type of shear connectors influences the crack pattern, concrete spalling degree, the deformation of the steel beam, and the difference in acceleration response between the concrete slab and steel beam, but on the whole, it has a limited effect on the damage mode and degree of SC composite beams subjected to contact explosion.

中文翻译：

---

接触爆炸作用下钢-混凝土组合梁的试验与数值研究

钢-混凝土组合梁由混凝土板、钢梁和剪力连接件组成，由于能有效利用材料性能且施工方便，在桥梁工程中得到广泛应用。考虑到爆炸事件对桥梁安全的重大影响，以及组合梁爆炸性能的试验研究有限，本研究对三种小型SC组合梁进行了试验，试验中布置了常用的剪力连接件，包括螺柱、PBL肋和组合连接件，与 200 克 TNT 接触爆炸。建立有限元模型并经实验数据验证，进行损伤分析，了解SC组合梁的损伤模式和特征。结果表明，SC组合梁在接触爆炸下表现出集中在梁跨中的局部损伤模式。底面混凝土剥落可被钢梁上翼缘分成两部分。混凝土板吸收了SC组合梁总内能的94%以上，对于减少梁在接触爆炸下的损伤起着最重要的作用。在某些方面，剪力连接件的类型会影响裂缝形态、混凝土剥落程度、钢梁变形以及混凝土板和钢梁之间的加速度响应差异，但总体而言，其影响有限。 SC组合梁接触爆炸损伤模式及程度。