喷涂抗爆型聚脲钢筋混凝土板抗爆性能研究

Research of Explosion Resistance of Sprayed Anti⁃blast Polyurea Reinforced Concrete Slab

为研究爆炸载荷下喷涂抗爆型聚脲QtechT26(T26)对钢筋混凝土板的防护效果,对T26进行热重分析(TGA),研究了其在高温环境下的热稳定性能;对T26涂层钢筋混凝土板开展了非接触爆炸试验,结合扫描电镜(SEM)和傅里叶变换红外光谱(FTIR),获得了在10 kg TNT作用下结构的宏观破坏模式和涂层的微观损伤行为;利用LS-NYNA对试验过程进行了数值模拟并与试验结果对比,分析了T26涂层对钢筋混凝土板抗爆性能的影响以及涂层的耗能机理。研究结果表明:T26的初始降解温度为265℃,最终降解温度为510℃,开始降解和降解结束时的温度均较高,具有良好的热稳定性;T26涂层钢筋混凝土板的主要破坏模式是迎爆面涂层产生了局部撕裂破坏并呈现高温烧蚀状,背面和侧面的涂层无破坏,内部钢筋混凝土板未发生明显变形;在爆炸冲击波和高温的耦合作用下,T26涂层的断面和表面出现了大量的熔融絮状物和撕裂状裂纹,且表面的总氢键化程度和完善氢键化程度与爆炸前相比分别下降了21.5%、18.2%;数值模拟与试验结果吻合度较高,表明数值模型具有可靠性,数值模拟下的T26涂层钢筋混凝土板可以吸收和转化更多的能量,抗爆效果更好。爆炸试验和数值模拟结果均证明了T26涂层可有效增强钢筋混凝土板的抗爆性能,可为聚脲在抗爆领域的研究提供重要参考。

In order to study the protective effect of sprayed anti⁃blast polyurea QtechT26(T26)on reinforced concrete slabs under explosive load,thermogravimetric analysis(TGA)was performed on T26,and its thermal stability under high temperature environment was studied.A non⁃contact explosion test was carried out on T26⁃coated reinforced concrete slabs,combined with scanning electron microscopy(SEM)and Fourier infrared spectroscopy(FTIR),the macroscopic failure mode of the structure and the microscopic damage behavior of the coating under the action of 10kg TNT were obtained.Using LS⁃NYNA to numerically simulate the test process and compare with the test results,the effect of T26 coating on the anti⁃blast performance of reinforced concrete slabs and the energy dissipation mechanism of the coating are analyzed.The research results show that the initial degradation temperature of T26 is 265℃,and the final degradation temperature is 510℃.The temperature at the beginning of degradation and the completion of degradation are both high,and it has good thermal stability.The main failure mode of the T26⁃coated rein⁃forced concrete slab is the partial tearing of the front surface coating and a certain bulge.The maximum bulge height is 30 mm,and the front surface presents a high⁃temperature ablation.The coating on the back explosion surface and the side surface is not damaged,and the internal rein⁃forced concrete slab is not significantly deformed.Under the coupling effect of the explosion shock wave and the high temperature,a large amount of molten flocs appear on the section and surface of the T26 coating.The total hydrogen bonding degree and the perfect hydrogen bonding degree of the surface are reduced by 21.5%and 18.2%,respectively,compared with before the explosion.The numerical simulation and the experimental results are in good agreement,indicating that the numerical model is reliable.The T26 coated reinforced concrete slab under the numerical simulation can absorb and transform more energy,and the anti⁃blast effect is better.Explosion test and numerical simulation results have proved that T26 coating can effectively enhance the anti⁃blast performance of reinforced concrete slabs,which can provide an important reference for the research of polyurea in the field of structural explosion protection.