预应力钢束锚固区局部应力分析及拉压杆模型的应用

Analysis of Local Stress and Application of Strut-and-tie Model in Prestressed Strand Anchorage Zone

钢束锚固区作为预应力构件的关键受力节点,长期以来一直是预应力混凝土桥梁量化计算的盲区,缺少成熟的设计理论。为了探寻一种较为准确、通用的设计方法,首先,对多种锚固区的受力特点进行了分析,通过横向对比多篇相关文献的内容,整理了拉压杆理论的计算过程,总结了拉压杆模型的设计方法和设计要点。接着,对一些关键参数的取用作了探讨与修正。最终,形成一套切实可行的拉压杆设计思路,为后续D区混凝土设计工作提供依据。

The steel strand anchorage zone as the critical stress node of prestressed component is always the dead zone of quantization calculation of prestressed concrete bridge for a long time. There is no the known design theory. In order to seek a more accurate and general design method, the article analyzes the stress characters of many anchorage zones, clears up the calculation process of strut-and-tie theory by horizontally comparing many relative literatures, summarizes the design methods and design gist of strut-and-tie model,discusses and amends some critical parameters, and forms a practical and feasible strut-and-tie design idea so as to provide the basis for the following design of D-zone concrete.