【摘要】 目前的预应力平板结构计算模式,对于预应力效应的计算多采用等效荷载法的概念,不适宜进行结构平面布置不规则、预应力束集中布置、有效预应力沿预应力束变化较大等情况下的内力分析计算,探求一种较好的预应力束作用分析模式成为急需解决的问题。本文基于预应力结构两阶段受力思想和有限元分析理论,针对预应力阶段的后张预应力混凝土平板结构,从混凝土体受力分析出发,运用虚功等效原理,推导了预应力束在预应力阶段所产生的等效结点荷载积分表达式,从而为平板结构预应力效应的计算提供了一种新的求解思路。另外从预应力束受力分析出发,运用虚位移原理,并区分有粘结与无粘结情况,提出了另一种形式更为简洁的预应力等效结点荷载积分表达式。更多还原

【Abstract】 The current calculation mode of prestressed slab employs the concept of the equilvant load method, which is not applicable to some cases such as the irregular arrangement of structure, the centrally laid tendons, and the change of efficient stress along the tendons. The sound analysis mode for the effect of tendons is demanded. From the analysis of the concrete body under load, a mathematical integral expression based on the idea of two-phrase loading and the theory of FEA is established for equivalent nodal loads induced by prestressing tendons with the application of the virtual work principle to post-prestressed slab during the phrase of prestressing. The offers a new way to analyze prestressed slab. Another mathematical integral expression is also achieved with the application of the virtual displacement principle to the tendons, which has a simpler form and distinguishes the difference between bonded and unbonded tendons.更多还原