POZD涂层钢筋混凝土板抗震塌性能

为研究POZD涂层钢筋混凝土板在接触爆炸作用下的抗震塌性能，对3种试验模型开展不同梯恩梯（TNT）当量的接触爆炸试验。通过对试验模型的毁伤状态观察及数据统计，研究分析了POZD涂层的破坏模式和抗震塌机理。结果表明：POZD涂层钢筋混凝土板具备较为优越的抗震塌性能，随着涂层厚度的增加，抗震塌能力逐渐增强，且震塌系数呈线性减小趋势；钢筋混凝土板喷涂8 mm厚POZD涂层后，抗震塌能力远优于内衬3 mm厚Q235b钢板；在集团装药接触爆炸（球面波）作用下，POZD涂层的毁伤模式为圆锥状鼓起，该鼓起为混凝土碎块和冲击波的复合冲击作用下出现较大塑性变形所致；当冲击荷载超过POZD材料的极限抗拉强度时，除在锥尖处出现较小的圆孔状剪切破坏外，涂层仍能保持整体完好并持续有效约束混凝土碎片，不致产生大面积震塌破坏；在高应变率、强动载作用下，POZD涂层仍然能够保持大变形、高塑性特性，通过自身大变形吸收冲击波能量，约束混凝土碎片，起到较好的抗震塌效果。

Anti-collapsing Performance of POZD Coated Reinforced Concrete Slab

Different TNT equivalent tests of three test models were made to study the anti-collapsing behavior of POZD coated reinforced concrete slab. The failure mode and anti-collapsing mechanism of POZD coating were studied and analyzed by observing the damage states and data statistics of the test models. The results show that POZD coated reinforced concrete slab has superior anti-collapsing performance, and with the increase in coating thickness, the anti-collapsing capacity increases gradually, and K_z decreases linearly. After spraying 8 mm-thick POZD coating on reinforced concrete slab, its anti-collapsing capacity is much better than that of 3 mm-thick Q235b steel plate. The damage model of POZD coating is conically bulged under the contact explosion of group charge, which is caused by large plastic deformation under the combined action of concrete fragment and shock wave. When the shock wave load exceeds the ultimate tensile strength of POZD material, the coating can remain intact and effectively restrain the concrete fragments except for the small circular hole shear failure at the tip of the cone. Under the action of high strain and strong dynamic load, POZD coating can still maintain the characteristics of large deformation and high plasticity. Through the large deformation of POZD coating, it absorbs the energy of shock wave, constrains the concrete debris, and plays a good anti-collapsing effect.