为了研究矩形切口对高耸烟囱定向爆破精准性的影响,结合杭州钢铁厂120 m高钢筋混凝土烟囱的结构特点和周边环境,通过理论计算和采用有限元分析软件 ABAQUS数值模拟,并对爆破过程和爆后效果进行了分析.结果表明:爆破过程中矩形切口支撑部分断裂处位于切口中上部,断裂线为非直线形状,产生下坐后,因底部不平整未能形成平整底部铰链转动,同时在向下冲量的作用下,影响了烟囱的倒塌方向的精准性,矩形切口对高耸烟囱定向倒塌的可控性较差,不建议在较为复杂环境下采用;同时,利用ABAQUS显式动力分析,还可以较好的还原烟囱倒塌过程.通过数值模拟与实际监测数据的对比,对工程实践具有一定的指导意义.%In order to research the effect of rectangular notch on the precision of directional blasting of towering chimney,this paper combines the structure characteristics and surrounding environment conditions of the 120 m reinforced concrete chimney of Hangzhou iron and steel plant.Through the theoretical calculation and numerical simulation with finite element analysis software ABAQUS,the blasting process and effect are analyzed.The results show that the fracture of the rectangular notch support is located in the upper middle of the notch during the blasting process,and the fracture line is not straight.After the backlash,failure to form a flat bottom hinge rotation because of unevenness at the bottom.Meanwhile, under the action of the downward impulse,the precision of the chimney collapsing direction is affected.The rectangular notch is fixed to the towering chimney.The controllability of collapsing is poor,and it is not recommended to be used in a more complex environment.Furthermore,this project use ABAQUS explicit dynamic analysis can better restore chimney toppling process,through a comparison of the numerical simulation and the actual monitoring data also has a certain guiding significance for engineering practice.
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