砼徐变系数拟合与共轭斜量法求解

Concrete Creep Coefficient Fitting and Conjugate Gradient Method Solving

根据砼的徐变特性,选用指数函数作为基函数,构造了最普遍的Dirichlet级数形式来拟合徐变系数.针对拟合过程中实际变量多于未知变量的特点,应用共轭斜量法求解法方程组,在此基础上对文献中提供的砼徐变试验数据进行了拟合,拟合结果与试验数据吻合良好,并讨论了Dirichlet级数形式中初始值的选取要求.

According to the creep characteristic of concrete, the exponential function was selected as base function, which could construct the prevalent Dirichlet series so as to fit creep coefficient. For the actual variables more than unknown ones, conjugate gradient method was adopted to solve the equations. Furthermore, the creep experiment data from reference were fitted by this method. The results showed that the fitted values were in good agreement with the experimental data. At last, the choice method of initial value in Dirichlet series was discussed.