高温下钢筋混凝土梁抗爆性能研究

Blast performance of reinforced concrete beams under high temperature

为研究钢筋混凝土(RC)梁在高温和爆炸荷载联合作用下的受力性能,通过ABAQUS有限元软件分别建立受火性能试验和抗爆试验的精细化有限元模型,并且通过与试验结果对比,验证所建立有限元模型的准确性。在此基础上,开展高温下RC梁抗爆性能研究,分析RC梁在不同爆炸距离和不同受火时间作用下的动力响应,讨论配筋率和剪跨比对高温下RC梁抗爆性能的影响规律。结果表明:在相同爆炸距离下,随着受火时间的增加,RC梁发生剪切破坏特征更加明显,跨中挠度也随之增大,受火时间为90 min工况与无受火工况相比,跨中挠度增大250%。配筋率的提高能明显增强RC梁在高温下的抗爆性能,而剪跨比的增大则明显降低RC梁在高温下的抗爆性能。

To explore the mechanical properties of reinforced concrete(RC)beams under the combined action of high temperature and blast loads,refined finite element models were established by ABAQUS software to simulate the fire performance test and the explosion resistance test.The accuracy of the established finite element models was verified by comparing with the experimental results.Then,the blast performance of RC beams under high temperature was studied.The dynamic response of RC beams under different explosion distances and fire durations was analyzed,and the effects of reinforcement ratio and shear span ratio on the explosion resistance behavior of RC beams under high temperature were discussed.The results show that at the same explosion distance,with the increase of fire duration,the shear failure characteristics of RC beams become more obvious,and the mid-span deflection increases.Compared with the condition without fire,the mid-span deflection increases by 250%after fire exposure for 90 min.The increase in reinforcement ratio can significantly improve the blast performance of RC beams under high temperature,while with the rise of the shear span ratio,the blast performance of RC beams at high temperature is obviously decreased.