【作者】 陈平友；

【导师】 简斌；

【作者基本信息】 重庆大学 ， 结构工程， 2002， 硕士

【摘要】 本文首先从理论上分析了影响后张有粘结部分预应力混凝土框架（简称为预应力框架）内力重分布和弯矩调幅的主要因素，即相对受压区高度、次弯矩和加载方式等，并初步分析了两榀只加竖向荷载和两榀既加竖向荷载又加水平荷载的单层单跨预应力框架静力加载的试验。接着，本文根据有限单元和力法原理、增量法及中点刚度理论，提出了本文暂且命名为曲率力法的非线性分析方法。该方法通过增加截面的曲率来反求框架外加荷载的增量，并在文中以试验的框架模型为例，给出了整个推导过程。该方法一并考虑了塑性铰、节点刚域、负刚度及单元卸荷等问题。然后本文利用曲率力法编制的非线性分析程序，模拟了预应力框架试验。计算结果表明，模拟计算和试验测试的过程和结果吻合较好，验证了该方法的可靠性和可行性。最后，本文利用编制的非线性程序，模拟了18榀单层单跨预应力框架，重点研究截面相对受压区高度、次弯矩、加载方式对塑性内力重分布和弯矩调幅的影响，从中得出了以下主要的结论和规律：(1) 框架梁相对受压区高度ξ在很大程度上反映了截面的延性，体现了塑性铰的转动能力，框架的总弯矩调幅系数随着相对受压区高度ξ的增大而减小。(2) 如果把次弯矩看着是对框架的一种弯矩调幅，在相同的相对受压区高度ξ下，次弯矩越大，次弯矩调幅作用越强；如果结构不能实现完全的内力重分布，则次弯矩能够延缓截面极限承载力的到来，提高结构的极限承载力，结构总的弯矩调幅系数也随着次弯矩的增大而增大。(3) 框架既承受水平荷载又承受竖向荷载时的总弯矩调幅系数比相同结构只承受竖向荷载的总弯矩调幅系数大。因此，在预应力框架设计中，可以取只承受竖向荷载的弯矩调幅作为其调幅标准，调幅弯矩为竖向荷载产生的弯矩与水平荷载产生的弯矩之和，即用最小的弯矩调幅系数来调整截面的弯矩。更多还原

【Abstract】 At first, this thesis analyzes the main causes in theory, which have effects on the redistribution of internal force and modulation of moment for the bonded post-tensioned partially prestressed concrete frame (for short prestressed frame), including the relative height of compressive zone of section (ξ), secondary moment and types of load applying. Then, this thesis analyzes the test of prestressed frame. Then, a method, called curvature-force method, for nonlinear analysis of prestressed frame is put forward. The method, based on the finite element theory, force-method theory, increment method and middle stiffness method, making use of the increment of curvature of the section, works out the increment of load applying and is proved in this thesis. At the same time, plastic hinge, rigid zone, negative stiffness, load relaxing and so on are taken into account. With curvature-force method, this thesis designs the program for nonlinear analysis and simulates the test. The results of nonlinear analysis are good agreement with the ones of test. So the method of nonlinear analysis is proved reliable and practical.At last, with the program, 18 one-storey and one-span prestressed frames are simulated. Some conclusions are reached with the taking into account the ξ, secondary moment and types of load applying: (1) The ξ in the beam affects the ductility of the section and rotary property of the plastic hinge. So total coefficient of the modulation of moment becomes less with the ξ becoming bigger. (2) If secondary moment is taken for one kind of modulation of moment and there are the same ξ, the effect of secondary moment on the modulation of moment becomes bigger with secondary moment becoming bigger. If prestressed frame can not complete full redistribution of internal force, ultimate load may put off and put up because of secondary moment. Total coefficient of modulation of moment also is bigger. (3) Total coefficient of modulation of moment for the frame applied horizontal load and vertical load is bigger than that of the same frame applied vertical load. So, for the design of prestressed frame, the later coefficient may be considered as the parameter of modulation of moment and the moment modulated is the moment caused by the vertical load plus the one by the horizontal load.更多还原