中文摘要：

对9块无粘结预应力混凝土连续板进行了受火性能的试验研究。通过对这些试验的综合分析，给出了出现裂缝的主要种类、成因及由此造成的破坏形式。根据裂缝的发展趋势和板的破坏形式说明了内力重分布的规律，并与由支反力推算得的弯矩变化规律相互验证。从火灾初期弯矩变化规律图可以发现，在受火的前5min，结构内己产生剧烈的内力重分布，火灾初期结构的内力重分布主要是由热膨胀应变引起的。根据板的破坏形式和预应力筋被拉断等现象提出了保证连续构件必要的耐火极限的防护措施。

英文摘要：

The behaviors of 9 unbonded prestressed co ncrete Continuous slabs are investigated under fire. From the test results, categories and reasons of cracks and failure modes caused by them are presented by analysis. Regulations of internal force redistribution are given by development tendency of cracks and failure modes of slabs, and were verified by regulation of moment variation precluded by reactions. Violent redistribution of internal force in structure at initial 5 minuets of fire. It was caused by thermal strains. Protection measures to assure fire endurance of continuous members were advised by failure mode of slabs and broken of prestressed steel under fire.