钢筋混凝土烟囱定向倒塌过程中后坐的判断

通过对抛物线型切口闭合阶段的力学分析，较全面地讨论了钢筋混凝土烟囱产生后坐的原因，得到了倒塌过程中的运动方程和相应的解析式。并且结合具体工程实例，介绍了在复杂环境下，一座210米高的钢筋混凝土烟囱，经前期人工拆除后，剩余75米部分采用抛物线型切口进行定向倒塌拆除设计。按照烟囱的结构和实际的受力状态，以烟囱后坐范围的预测为重点，为拆除钢筋混凝土烟囱，正确选择有关参数提供理论依据。

Judgment of Recoil during Directional Collapse of Reinforced Concrete Chimney

According to the mechanical analysis in the stage of parabolic cut closed,the causes of recoil phenomena are comprehensively discussed. During directional collapse, motion equations and the relevant analysis formulas are given with an example. After manually demolishing the reinforced concrete chimney with a height of 210 meters, by directional collapse demolition with parabolic cut the design of remainder with a height of 75 meters is introduced at complex circumstance. With chimney structure and actual stressing state,scope of recoil is predicted. It＇s helpful to optimize the parameters of demolishing reinforced concrete chimney and provide some theoretical basis.