Abstract

There are no contemporary code requirements for the fire resistance of bridge infrastructure, nor is there guidance available for practitioners who wish to design cable-supported structures for the fire. This research seeks to develop an understanding of the thermal response of steel stay-cables under exposure to a pool fire. Multiple varieties of locked coil and spiral strand stay-cables are instrumented with thermocouples and heated by a methanol pool fire. Novel imaging techniques observe the cables’ surface during heating and cooling and enable the calculation of thermal strains and deformations. Results herein illustrate a normalisation of cross-sectional temperatures outside of the localised heating region for cable diameters up to 140 mm, provide comparisons of heat transfer behaviours for different cable sizes and configurations, present novel thermal rotational effects, and calculation of cable thermal expansion values. Predictive thermal expansion values provided by the Eurocode are shown to underpredict cable thermal expansion in most cases.

摘要

对桥梁基础设施的耐火性没有当代规范要求，也没有为希望为火灾设计电缆支撑结构的从业者提供指导。本研究旨在了解钢拉索在暴露于池火下的热响应。多种锁定线圈和螺旋绞线拉索配备热电偶，并由甲醇池火加热。新的成像技术在加热和冷却过程中观察电缆的表面，并能够计算热应变和变形。本文的结果说明了电缆直径最大为 140 mm 的局部加热区域之外的横截面温度的标准化，提供了不同电缆尺寸和配置的传热行为的比较，提出新颖的热旋转效应，并计算电缆热膨胀值。在大多数情况下，欧洲规范提供的预测热膨胀值显示低估了电缆的热膨胀。

抽象的

对桥梁基础设施的耐火性没有当代规范要求，也没有为希望为火灾设计电缆支撑结构的从业者提供指导。本研究旨在了解钢拉索在暴露于池火下的热响应。多种锁定线圈和螺旋绞线拉索配备热电偶，并由甲醇池火加热。新的成像技术在加热和冷却过程中观察电缆的表面，并能够计算热应变和变形。本文的结果说明了电缆直径最大为 140 mm 的局部加热区域之外的横截面温度的标准化，提供了不同电缆尺寸和配置的传热行为的比较，提出新颖的热旋转效应，并计算电缆热膨胀值。在大多数情况下，欧洲规范提供的预测热膨胀值显示低估了电缆的热膨胀。