闸墩施工期温度应力仿真分析  

Simulation Study of Thermal Stress in Pier

作　　者：朱秋菊[1] 韩菊红[1] 乐金朝[1] 

机构地区：[1]郑州大学环境与水利学院,河南郑州450002

出　　处：《郑州大学学报（工学版）》2005年第1期47-49,53,共4页Journal of Zhengzhou University（Engineering Science）

基　　金：河南省科技攻关项目(0324240013)

摘　　要：考虑外界气温条件、水泥水化热、弹模、徐变等热力学和物理力学参数以及分层浇筑(利用生死单元实现分层浇筑)对闸墩温度应力的影响,利用ANSYS软件三维有限元法进行闸墩施工期的瞬态温度场和应力场仿真计算.结果表明:内外温差过大,内部温升温降太快是闸墩出现裂缝的主要原因,并提出了对拌合材料冷却,降低浇筑温度,采用优化的保温保湿养护方法,在混凝土内预埋冷却水管,选用低热水泥,使用减水剂等减小内外温差,减缓温升温降过程,以有效防止施工期表面裂缝的产生.The 3-D mesh method is used to analyze the transient temperature field and temperature stress of the piers during placement. The variations of elastic modulus, creep, hydration and atmosphere temperature variation related to the age of concrete and the effect of layered placement (using killing and reactivating elements to realize layered placement) are taken into account. Measures for preventing from surface cracking caused by atmosphere temperature variation and hydration of concrete in the process of construction are proposed. The main cause of surface cracking is analyzed and it lies in the difference between inner and outer temperatures is too large and the rising and decreasing of inner temperatures is too fast. Measures for avoiding surface cracking are proposed: cooling the blending materials, decreasing the original temperature of the placement, taking optimizing methods of keeping certain temperature and humidity, embedding cooling water pipes in the concrete previously, selecting the cement of low heat and using water-reducing agent.

关 键 词：内外温差 温度应力 湿养护 水泥水化热 保温保湿 分层浇筑 施工期 闸墩 浇筑温度 冷却水管 

分 类 号：TU755[建筑科学—建筑技术科学] TU528