烟囱高度超过210 m时，采用等曲率法计算烟囱附加弯矩存在较大误差。提出了一种烟囱附加弯矩计算方法，该方法基于共轭梁理论，并对烟囱刚度进行折减。以某烟囱工程为实例，用该方法计算了烟囱在水平风荷载作用下的附加弯矩和水平变位。为了验证该方法的可靠性，应用有限元软件ANSYS的计算结果进行对比，算例结果证明了该方法的有效性。

When a chimney reaches over 210 m in height, significant errors will occur if the even curvature method is used to calculate additional bending moments. A method is proposed for precise calculation of the additional bending moments of the chimney, which is based on the theory of conjugate beam, along with the chimney stiffness being reduced. By taking a chimney project as a case study, the method is used to calculate the additional bending moments and the lateral deflections under the lateral wind loads. In order to verify the calculation results by this method, the ANSYS software is used to make a comparison, which has proved the reliability of this method.