【作者】 郭全意；

【导师】 周茗如；

【作者基本信息】 兰州理工大学 ， 结构工程， 2011， 硕士

【摘要】 随着国民经济的飞速发展,工业与民用建筑中超长、超厚以及异形的大体积混凝土结构日趋扩大和复杂。与一般的钢筋混凝土相比,大体积混凝土具有边界条件复杂、几何尺寸较大、施工技术和质量要求较高等特点。大体积混凝土在施工过程中,经常发生由于不同应力场作用下所引起的应力而使混凝土产生结构性裂缝。随着混凝土龄期的增长,裂缝有时甚至还会贯通。这些裂缝与干缩裂缝一起,不仅降低了结构物的耐久性,而且严重时还会影响结构的正常使用。准确预测大体积混凝土的应力场是有效控制早期裂缝的保障,因此基于应力场的大体积混凝土早期裂缝监控与预测,是大体积混凝土施工质量控制的一个重要的研究课题。本文结合中国石油庆阳石化公司300万吨搬迁改造项目中的大体积混凝土工程,阐述了基于应力场的大体积混凝土早期裂缝产生的原因及影响因素;分析了大体积混凝土结构边界条件、几何尺寸以及配筋率对应力场的影响;初步探讨了温度因素以及非温度因素所引起的不同应力场;重点总结出了温度因素所引起应力场的计算方法以及大体积混凝土早期施工质量控制的具体技术措施。基于热传导基本理论,结合工程实例,介绍了有限元分析的原理及一般的模拟分析过程,运用大型有限元分析软件ANSYS ,对大体积混凝土施工过程进行了仿真模拟,预测其早期应力场的分布情况,从而为大体积混凝土的早期施工质量控制提供理论参考依据,并将所得结果与实测结果对比分析,结果表明ANSYS的仿真分析可以为大体积混凝土早期施工质量控制提供技术参考。更多还原

【Abstract】 With the rapid development of the national economy, industrial and civil buildings with long, thick and shaped in large concrete structure are increasingly expending and complex. Compared with the normal reinforced concrete, mass concrete complex with boundary conditions, geometric size larger, construction technology and high quality requirements and so on. Mass concrete in the construction process,often occurring due to different stress field caused by the stress of leaving a structural cracks in concrete. With the increase in age of concrete, the cracks will even through sometimes. These cracks and shrinkage cracks together, not only reduces the durability of the structure, but also affect the structure of normal use. It is the protection of mass concrete early crack control that the stress field is accurately predicted. Therefore,it is an important that the stress field based on massive concrete early cracks monitoring and prediction is the quality control of mass concrete construction .This paper is based on the Qingyang Petrochemical Company of China 3 million tons of oil reconstruction project in the relocation of mass concrete, Describes the causes and the factors of the early cracks based on the stress field; Analysis the impact of mass concrete structures boundary conditions,geometry and reinforcement ratio for the stress field; Discussed preliminary the different stress field caused by the temperature factors and non-temperature factors. The key to summed up the calculation of stress field caused by the temperature factors and the early mass concrete construction quality control of specific technical measures.Based on the basic theory of heat conduction, with engineering examples , the principle of the finite element analysis and the general principles of simulated analysis are introduced ,using finite element analysis software ANSYS, for mass concrete construction process was simulated, predicting its early stress distribution, so as to provide a theoretical reference for the early construction of mass concrete quality control, and the results compared with experimental results, the simulation results show that the ANSYS analysis for the early quality control of mass concrete construction to provide technical reference.更多还原