说明：  PQ-Fiber 是清华大学土木工程系结构工程研究所基于大型通用有限元程序ABAQUS 开 发的一组材料单轴滞回本构模型的集合。主要用于在钢筋混凝土结构、钢结构等的弹塑性时 程分析中定义杆系结构的材料本构，同时可用于任何只需要定义材料单轴滞回本构模型的情 况。 作者以 FORTRAN 编译文件.obj 的形式在网上免费发布PQ-Fiber 的最新版本，以供广 大科研与工程设计人员使用，发布的版本没有功能限制。请使用者尊重知识产权，
(PQ-Fiber is a Structural Engineering Research Institute of Civil Engineering Department of Tsinghua University. It is based on the large general finite element program ABAQUS. A set of uniaxial hysteretic constitutive models is set up. It is mainly used for elastic-plastic properties of reinforced concrete structures and steel structures. In the process analysis, the material constitutive equation of the bar structure is defined, and it can be used for any material requiring only a uniaxial hysteretic constitutive model. The situation. The author releases the latest version of PQ-Fiber on the Internet for free in the form of FORTRAN compiler.Obj. The use of large research and engineering designers has no functional limitations. Invites users to respect intellectual property rights,)