爆炸荷载作用下粘贴Polymer Sheet膜材砌体墙防护性能研究

Protective performance of masonry walls strengthened with polymer sheet under explosive loading

以混凝土砌体墙爆炸试验为基础,借助LS-DYNA软件,分析混凝土砌体墙在爆炸荷载作用下的破坏机理及Polymer Sheet膜材加固后的防护性能。研究结果表明:爆炸荷载作用下,墙体背爆面跨中位置、迎爆面上下端部为危险截面,最易破坏;爆炸荷载的峰值压力不超过0.385 MPa时,砌块之间脱离和飞溅较少,可不进行防护;当峰值压力大于0.385 MPa时,随峰值压力增大,破坏部位脱离的砌块数量增多,飞溅速度加快,对建筑物内部人员及设施威胁增大,必须进行防护加固;峰值压力不超过0.95 MPa时,膜材能够很大程度上发挥防护作用,阻挡散落砌块的抛射;当峰值压力大于0.95 MPa时,膜材自身在锚固处断裂,墙体与断裂的防护膜以整体形式向建筑内部抛射,建议此时采用索膜防护体系,以提高防护效果;最后给出了Polymer Sheet膜材加固的砌体墙安全防护距离,以供设计参考。

Based on explosion tests of concrete masonry walls, the failure mechanism of concrete masonry walls and the protective performance of masonry walls strengthened with polymer sheet were analyzed. The results showed that the dangerous cross sections of a masonry wall are located in mid-span at its back and upper and lower ends facing to explosion; when the peak pressure of explosive loading does not exceed 0.385MPa, the blocks detaching from the wall and launching into a building are less, the wall should not be strengthened with polymer sheet; when the peak pressure exceeds 0.385MPa, the number of the blocks detaching from the wall increases with increase in the peak pressure, and the flying speeds rise too, and the threat against persons and equipments in the building grows, so the wall should be strengthened; when the peak pressure does not exceed 0.95MPa, polymer sheet can effectively work and hinder the cracked masonry from blocking; when the peak pressure exceeds 0.95MPa, polymer sheet breaks at anchorages, and the broken ploymer sheet launchs into the building with the broken wall, so a cable-membrane protective system should be installed to enhance the safety; the safe protection distance of the concrete masonry wall strengthened with polymer sheet is given. All results provided a reference for design.