位于西安地区某砖烟囱由于使用年代久远,老化损坏严重,加之汶川地震影响,其目前的使用状况不仅难以满足正常使用和耐久性的要求,并且对结构安全造成威胁。根据烟囱现场勘查及计算结果,分析其产生变形和裂缝的原因,对存在裂缝的筒壁进行全面配筋现浇混凝土进行加固,裂缝较宽处采用配筋水泥砂浆填缝的修补方法。利用基于位移型变分原理的非时间步参数时间有限元法对烟囱动力特性反应进行初步分析,加固后其基本自振频率大大提高,降低了风共振的发生率。同时,加固后的烟囱最大应力满足不会出现应力裂缝,消除了安全隐患,提高了可靠性,完全满足使用要求,对同类工程具有一定参考价值。 A brick chimney located in Xi’an area, due to its long-term use and serious aging and damage, combined with the Wenchuan earthquake, is not only difficult to meet the requirements of normal use and durability, but also poses a threat to the structural safety. Based on the site investigation and calculation results of the chimney, the causes of deformation and cracks were analyzed. The concrete wall with cracks was reinforced with cast-in-place concrete. The wider cracks were repaired with grouted cement mortar. Based on the displacement-based variational principle, the non-time-step time-varying finite element method is used to analyze the dynamic response of the chimney. The fundamental natural frequency of the chimney is greatly enhanced and the incidence of wind resonance is reduced. At the same time, the maximum stress of the reinforced chimney will meet the stress cracks will not occur, eliminating the potential safety hazards and improve the reliability, fully meet the requirements of the use of similar projects with some reference value.