Simulation Analysis Of Bulk Concrete Temperature Field

Mass concrete structures have been widely used in the major loading area of the dams, long span beams and High-rise buildings. Influenced by the changes of temperature outside and inside during the casting process, cracks in the body or surface of the concrete will be produced,which affect the function of the project structure. Due to the widespread and complexity of cracks, it requires further effective analysis of why the cracks will be occurred.At the same time, study on the crack evolution, trends, and the crack instability and other issues become an urgent and important task,which is not only the key to understand the existence of cracks of the massive concrete structure, but also has great practical values in guiding the management of construction and safe operation of the buildings.To systematically study the mechanism of the temperature cracks of mass concrete, this thesis analyzes the following issues:1. Started from the concrete mechanical and thermal properties, this thesis analyze the principle of temperature stress. From the perspective of Micro-mechanics and fracture mechanics, the thesis focused on the cracking mechanism of concrete structures, analyzed the temperature changes during cement concrete aggregate and temperature stress on the interface and the interface crack initiation and propagation, and finally find out the discipline of how the cracks is changed with the propagation temperature.2. Based on the former study on calculations of temperature field and temperature stress, this thesis concluded a simple estimation methods in practical application of temperature and thermal stress,discussed the validity of the ABAQUS finite element software's appliance of temperature and stress field.3. The thesis, made the actual project as an example, firstly discrete section of the gate body according to the actual situation of concrete construction, secondly apply the boundary conditions and temperature loads by using finite element software ABAQUS for concrete structure on the instability temperature and the stress field in the simulation, thirdly analyze whether the cracking of concrete will occur by comparing the tensile strength with the given nodes temperature and stress values.4. Based on the experience of relevant engineering the thesis applies the finite element method to analyze the cracks that will appear on the structure. In order to avoid temperature cracks in the structure. the thesis put forward reasonable arrangements for project in the following aspects:the concrete pouring and curing, materials, design and construction technology, and other construction sequence, optimization of concrete mix, control placing temperature, the incorporation of fiber, additional temperature of steel, setting the corresponding strengthening band and other remedial measures,which are aimed to prevent cracks and fissures temperature control measures.