To reveal the temperature characteristics and mechanical properties of frame structures with concrete filled steel tube reinforced concrete (CFSTRC) columns under fire, the fire resistance of four planar frames consisting of CFSTRC columns and reinforced concrete (RC) beams subjected to ISO-834 standard fire was tested in this study. The test parameters included the column fire load ratio, beam fire load ratio, and beam-to-column linear stiffness ratio. In the test, the temperatures of the column, beam, and slab cross-sections in the joint and nonjoint zones were measured, and the fire resistance, beam and column deformation curves, and failure modes of the frame were investigated. The experimental results showed that the concrete volume was the main factor affecting the temperature distribution on each typical cross-section of the frame: the temperatures at the measuring points of the beam and column in the joint zone were significantly lower than the temperatures at the corresponding points in the nonjoint zone, and the concrete outside the steel tube significantly slowed the propagation of temperature to the steel tube and its concrete core. Hence, there was only a small loss of the bearing capacity of steel tube and the core concrete inside the steel tube. The column fire load ratio, beam fire load ratio, and beam-to-column linear stiffness ratio have obvious influences on the fire resistance: the larger the column fire load ratio or beam fire load ratio, the smaller the fire resistance; and the larger the beam-to-column linear stiffness ratio, the larger the fire resistance.

为了揭示钢管混凝土柱（CFSTRC）着火时框架结构的温度特性和力学性能，由CFSTRC柱和钢筋混凝土（RC）梁组成的四个平面框架的耐火性均经过ISO-834标准防火在这项研究中进行了测试。测试参数包括柱的火荷载比，梁的火荷载比和梁与柱的线性刚度比。在测试中，测量了接缝区和非接缝区的柱，梁和平板横截面的温度，并研究了框架的耐火性，梁和柱的变形曲线以及破坏模式。实验结果表明，混凝土体积是影响框架各个典型截面温度分布的主要因素：接头区域中梁和柱的测量点处的温度明显低于非接头区域中相应点的温度，钢管外的混凝土显着减慢了温度向钢管及其混凝土的传播核。因此，钢管和钢管内部的核心混凝土的承载力仅有很小的损失。柱的火荷载比，梁的火荷载比和梁柱的线性刚度比对耐火性有明显的影响：柱的火荷载比或梁的火荷载比越大，抗火性越小。梁与柱的线性刚度比越大，耐火性就越大。