Study on the model of creep and the calculation of stress field for concrete

摘要

The exact prediction of creep is of great significance to the simulation of the stress field of concrete creep. To overcome the use limitation of the current prediction model of creep, we refer to pertinent models abroad and adopt the method that other factors are controlled under standard state but only the creep varies to evaluate the feasibility of the prediction model with current characteristic of concrete materials and available test data. In the prediction of creep of high performance concrete, each influencing factor can be quantified, so we don't need a large number of test data. It also supplements the defect that factors considered are usually simple in the common prediction model of concrete. The calculation is simple and convenient and it achieves a higher accuracy. In the calculation of creep stress field, the creep is calculated according to fitting creep degree. Based on it,, this paper established the creep coefficient formulas in the calculation of strain increment, and deduces the number of finite element expressions which are used to calculate the creep stress field with creep coefficient.