Abstract

External post-tensioning has proven to be an effective solution to introduce intermediate supports in structures in order to decrease their spans and to allow a more efficient distribution of bending moments. This leads to important savings in terms of material. However, this increase in effectiveness is achieved only for a specific loading, which generally corresponds to the permanent load distribution. This paper introduces the possibility of expanding the benefits of this technique to situations where relevant live loads act through the use of a responsive external post-tensioning system. The responsive behaviour is materialized through an actuator located between the beam and the post-tensioning system. After a brief overview of the existing responsive structures, this research studies the static structural behaviour of responsive externally post-tensioned structures. Furthermore, the main design variables are parametrically analysed and the applicability of the system is evaluated with the construction of a small-scale prototype. Finally, results are discussed and the effectiveness of this approach in terms of material savings is claimed.

摘要

事实证明，外部后张紧是将中间支撑引入结构中以减小其跨度并允许更有效地分配弯矩的有效解决方案。这样可以节省大量材料。但是，这种有效性的提高仅对于特定的负载才能实现，该负载通常对应于永久负载分配。本文介绍了通过使用响应性外部后张紧系统将这种技术的优势扩展到相关活荷载作用的情况的可能性。通过位于梁和后张紧系统之间的致动器来实现响应行为。简要概述了现有的响应式结构之后，这项研究研究了响应的外部后张结构的静态结构行为。此外，对主要设计变量进行参数分析，并通过构建小型原型来评估系统的适用性。最后，讨论了结果并声称这种方法在节省材料方面是有效的。