Three Dimension Finite Element Researches On Temperature Field And Thermal Stresses Of Mass Concrete

With the widely application of mass concrete structure in modem engineerings ,the concrete crack resulted from temperature stress are getting more and more attention of people. But the factors affecting concrete crack are various and the mechanism of generating the crack is complex and there are so many research findings home and overseas, precise simulation of the influence of all kinds of factors on crack generation and development is impossible at present. The general FEM analysis softwares are unable to simulate actual construction precisely. Although the programs for temperature controlling are various, every program, which basically are closed, has different emphasis and its merit .On this background ,in the paper ,based on theories studied before, program made by tutor for computing 3-D temperature and stress fields of mass concrete is validated by examples under lots of work conditions , according to thermodynamics characteristics of mass concrete, aimed at improving the computation efficiency of temperature and stress fields of mass concrete. On the precondition of precision, the work of data input is simplified. By optimization of the program, speed of computation is highly advanced, leading to better results in single PC.For using program efficiently, complex data handling is included in core compute program, so the preparation for data is as simple as common structure analysis. In modeling, the elements and nodes of every batch of concrete needn't be coded by sequence, simplifying the element division greatly, moreover nodes are optimized and the speed of calculation is improved.On the basis of a simple case, taking a overfall dam in a certain engineering as an example, according to actural construct conditions and engineering information, dam construct processes are simulated. Through the analysis of temperature field and stress field, the maximum stress and appearance time are found. Furthermore, sensitiveness of program to temperature and stress fields is validated by changing temperature-keep measures and decreasing warehousing temperature.