摘要
为进一步研究复杂条件下高耸烟囱分段控制爆破拆除技术,利用高速摄影对钢筋混凝土烟囱高位切口上段筒体爆破拆除倒塌过程进行拍摄,并采用共节点分离式模型,利用DYNA非线性有限元软件对烟囱上段筒体爆破拆除倒塌过程进行了数值计算。结果表明:数值模拟结果和实际吻合较好;高位切口上段筒体倒塌过程可分为爆破切口形成、切口支撑部位变形破坏、筒体下座及定向倾倒和触地解体破碎四个阶段;高位爆破切口形成后,烟囱经历2 s左右时间进行应力重新分布是烟囱完成安全、定向准确爆破拆除的关键条件;高位切口支撑部位变形破坏由受压区开始,向受拉区发展,在此过程中,中性轴向后移动,轴向钢筋受压屈服。
In order to research the segment controlled explosive demolition technology of tall chimneys under the complex conditions ,the collapse process of the chimney was imaged by high-speed photography and simulated by using DYNA nonlinear finite element software with common node separate models. The results show that the numerical simulation results agreed with the actual results well ; the collapse process of upper chimney with high altitude incision could be divided into four stages, including the formation of blasting cut ,deformation damage of incision support part, sit with directional collapse and touchdown with disintegration ; after the high location blasting cut formed, the stress redistribution of chimney ＇after 2 seconds was the key condition for the safely chimney collapse; the deformation damage of incision support part started at the concrete of the compression zone and developed towards the tension zone. Meanwhile,the neutral axis gradually moved backward and the axis reinforced bar bending yielded in this process.
出处
《爆破》
CSCD
北大核心
2016年第3期96-100,共5页
Blasting
基金
国家自然科学基金(52474218)
关键词
钢筋混凝土烟囱
高位切口
爆破拆除
共节点分离式模型
数值模拟
reinforced concrete chimney
high location cut
explosive demolition
common node separate model
numerical simulation
