Development of Fire Protection Panel in Steel-Concrete Composite girder bridge

近年来，在日本乃至国外，因油罐车翻车事故、燃烧弹等引起的桥梁火灾有增加的趋势。2008年8月初在日本发生的都市高速公路池袋线事故就是其中一例。在这种情况下，由于支座区域的剪切屈曲，钢梁高度从1200mm下降到700mm。结果，这条城市高速公路关闭了大约两个半月进行维修。据大都会高速公路株式会社公布，此次事故造成的经济损失约为45亿日元。为了防止火灾对桥梁造成严重的破坏，笔者建议仅在高架桥或普通桥梁发生火灾事故可能性较大的情况下采用防火面板。作者对加和不加FPP的钢-混凝土组合梁进行了防火试验。本文报道了FPP的概要和钢梁内部温度分布的实验结果。

Recently, the fire attack for the bridges due to turning over accident of a tank lorry vehicle, incendiary fire and so on trends to increase in Japan and also in foreign countries. One of the examples of such accident in Japan occurred in Ikebukuro line of Metropolitan Expressway at the beginning of August in 2008. In this case, the height of the steel girder was sunk from 1200mm to 700mm due to shear buckling in the region of the support. As a consequence, this urban expressway was closed about two and half months for repairs. According to the announcement of Metropolitan Expressway Company Limited, the economic loss by this accident reached to approximately 4.5 Billion Yen. To prevent a serious damage of the bridge due to fire attack, the authors have been proposed the adoption of Fire Protection Panel (hereafter referred to as FPP) for the viaduct or normal bridge only where they have high occurrence possibility of fire accident. The author carried out the fire test of steel-concrete composite girder with and without FPP. This paper reports on the outline of the FPP and the experimental results of the temperature distributions in the steel girder.