混凝土徐变应变全量递推方法研究及程序设计

混凝土在长期荷载作用下的徐变变形与应力作用历史密切相关,常见的徐变计算方法需记录每一步应力变化,占用大量的存储和计算空间,效率低;采用指数形式徐变度函数可利用指数特点建立只记录当前应力的增量递推式,但不适于应用更广泛的非指数函数形式徐变预测模型.应用徐变恢复理论和应力冲量持时函数,建立了不需记录全部应力历史的全量递推方...

Total variables recurrence method of concrete creep and program design

Under long-term loads, concrete creep deformation was not only connected with current stress, but also depended much on the stress history. Generally, every step of creep calculation methods needs to memorize the whole stress history, causing very poor computing efficiency. Making use of the traits of exponential function, creep increment recurrence that only memorizing current stress could be established. While, for many kinds of non-exponential creep function applied in the design codes, the increment formula was not applicable any more. Based on creep recovery theory and stress impulse function, the total variables recurrence method was presented. Visual Fortran was applied into compiling general analysis program, and the program design flow was shown. By research and application, it was indicated that this method could meet precision requirement by memorizing part of stress history, and improve the calculation efficiency greatly. And the method was fit for different kinds of creep and loading modes. At last, the primary factor values were suggested for different types of creep function.