Purpose

The purpose of this paper is to investigate the explosive performance and explosion damage mechanism of T-beam bridge structure.

Design/methodology/approach

On the basis of the existing specification, two T-beam bridge models were designed and fabricated. Test specimens of different explosive dosage and different blast height were carried out. The mechanical process, failure mode, blast damage model, damage identification mechanism and blast evolution law and quantitative evaluation were taken into account.

Findings

The results revealed that the web plate fracture failure is the key to the unstable failure of the whole T-beam bridge. The explosion failure phenomenon and blast damage evaluation criterion of RC T-beam bridge was divided into five stages: the original cracks stage of concrete material (D = 0 ∼ 0.1), the fractures initiation stage of concrete material (D = 0.1 ∼ 0.3), the stable expansion stage of cracks in concrete material (D = 0.3 ∼ 0.55), the unstable expansion stage of cracks in concrete material (D = 0.55 ∼ 0.8), the explosion fracture of steel bars and the overall instability and damage of the bridge (D = 0.8 ∼ 1.0), which can also be described as basically intact, slight damage, moderate damage, severe damage and collapsed.

Social implications

The research result will provide basis for the antiknock evaluation and damage repair technical specifications of the RC T-beam bridge.

Originality/value

The research results of damage evaluation serve as a basis for damage repair and reinforcement of bridge structures after explosion.

中文翻译：

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钢筋混凝土T型梁桥爆破破坏试验研究

目的

本文的目的是研究T型梁桥结构的爆炸性能和爆炸破坏机理。

设计/方法/方法

在现有规范的基础上，设计并制作了两个 T 型梁桥模型。进行了不同炸药剂量和不同爆炸高度的试验样品。综合考虑了力学过程、破坏模式、爆炸损伤模型、损伤识别机制和爆炸演化规律，定量评价。

发现

结果表明，腹板断裂破坏是整个T型梁桥不稳定破坏的关键。RC T型梁桥爆炸破坏现象及爆破损伤评价准则分为5个阶段：混凝土材料原始裂缝阶段（D=0~0.1）、混凝土材料断裂萌生阶段（D=0.1~0.3） , 混凝土材料裂缝稳定扩展阶段（D = 0.3 ∼ 0.55），混凝土材料裂缝不稳定扩展阶段（D = 0.55 ∼ 0.8），钢筋爆炸断裂和桥梁整体失稳破坏(D = 0.8 ∼ 1.0)，也可描述为基本完好、轻微损坏、中度损坏、严重损坏和倒塌。

社会影响

研究成果将为钢筋混凝土T型梁桥抗爆性评价和损伤修复技术规范提供依据。

原创性/价值

损伤评价研究成果为桥梁结构爆炸后损伤修复与加固提供依据。