Abstract：In order to investigate the protection method of reinforced concrete π-beam under near-field explosion load, ANSYS/LS-DYNA was used to establish the beam explosion numerical model. According to the results of field explosion test, the failure modes of beam under explosion load are compared, and the accuracy of numerical model is verified. Based on the numerical analysis of different protection forms of π-beams under explosive loads, we studied the peak distribution of shock wave overpressure under different protection conditions, the law of structural energy consumption, the damage pattern of the π beam after protection, and the protection efficiency of different protective layers. The testing results indicate that the peak value of shock wave overpressure is relatively small under the combined protection of steel plate and aluminum foam. Besides, as the longitudinal distance increases, the impact overpressure attenuates most heavily on the roof's explosion-facing surface. Meanwhile, the combined protective of steel plate and aluminum foam layer has a strong energy consumption capacity, the energy consumed by accounts for 90% of the three parts of the π beam (concrete, steel, and protective layer). The failure mode of π-beams under various protective conditions is a partial failure, without overall deformation or damage to the flange plate and web. The damaged area of π- beam is relatively small under the combined protection of steel plate and aluminum foam, and the combined protection layer is relatively good.
刘超1，孙启鑫1，李会驰2. 近爆作用下钢筋混凝土π梁防护性能的数值模拟[J]. 振动与冲击, 2022, 41(4): 223-231.
LIU Chao1, SUN Qixin1, LI Huichi2. Numerical simulation for protective of reinforced concrete π beams under close-in explosion. JOURNAL OF VIBRATION AND SHOCK, 2022, 41(4): 223-231.
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