Concrete-filled steel plate composite walls are increasingly used in high-rise buildings; their mechanical properties at room temperature have produced fruitful results. However, research on their mechanical properties in fire and at high temperatures is scarce. Moreover, published studies on the fire resistance of concrete-filled steel plate composite walls have not considered the impact of fire protection measures. Based on previous fire resistance research, a fire resistance test was designed in this study for four walls under the combined action of axial compression and a single-sided fire under the ISO-834 standard heating curve. Apart from that, the existing fire protections have the disadvantages of too thick, easy falling off and cracking or difficult to install. In order to eliminate the disadvantages of existing fire prevention measures, new composite fireproof structure using a rock wool board and a thin fire-retardant coating is proposed. The effects of no fireproof structures, autoclaved lightweight concrete plate fireproof structures, thick-coated fire-retardant structures, and new composite fireproof structures on the fire resistance of concrete-filled steel plate composite walls were studied experimentally. The results show that the fire resistance of the four test specimens meets the 3 h fire resistance limit of the primary load-bearing component in the specification. Based on the experimental results, reasonable fire protection methods are suggested for concrete-filled steel plate composite walls in actual projects, and an experimental basis is provided for further numerical simulation.
