钢结构防火涂料在火灾条件下的性能退化规律研究 -土木工程专业

摘要

钢结构在现代建筑中具有广泛应用，但其耐火性能较差，在火灾条件下易发生强度退化和结构失效。为提升钢结构的防火性能，防火涂料被广泛应用于工程实践，然而其在高温火灾条件下的性能退化规律尚不明确。本研究旨在系统分析钢结构防火涂料在火灾环境中的性能变化机制及其影响因素。通过设计高温加热试验，结合热重分析（TGA）、差示扫描量热法（DSC）以及微观结构表征技术，对不同类型防火涂料的热分解行为、隔热性能及残余力学性能进行了深入研究。结果表明，防火涂料的性能退化与其化学成分、涂层厚度及升温速率密切相关，其中有机成分的热分解是导致隔热性能下降的主要原因。此外，研究发现引入纳米增强材料可显著改善涂料在高温条件下的稳定性，从而延缓性能退化。本研究揭示了防火涂料在火灾条件下的性能退化规律，并提出了优化改性的新方法，为提升钢结构防火安全性能提供了理论依据和技术支持，具有重要的工程应用价值。

关键词：钢结构防火涂料；火灾环境；性能退化规律；纳米增强材料；热分解行为

ABSTRACT

Steel structures are widely used in modern architecture, but their poor fire resistance makes them susceptible to strength degradation and structural failure under fire conditions. To enhance the fire protection of steel structures, fire-retardant coatings have been extensively applied in engineering practice; however, the degradation mechanisms of these coatings under high-temperature fire conditions remain unclear. This study aims to systematically investigate the performance variation mechanisms and influencing factors of fire-retardant coatings for steel structures in fire environments. High-temperature heating tests were designed in conjunction with thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and microstructural characterization techniques to comprehensively examine the thermal decomposition behavior, insulating performance, and residual mechanical properties of different types of fire-retardant coatings. The results indicate that the performance degradation of fire-retardant coatings is closely related to their chemical composition, coating thickness, and heating rate, with the thermal decomposition of organic components being the primary cause of reduced insulating performance. Additionally, it was found that incorporating nanoscale reinforcing materials significantly improves the stability of coatings under high-temperature conditions, thereby delaying performance degradation. This research elucidates the degradation patterns of fire-retardant coatings under fire conditions and proposes novel optimization methods, providing theoretical support and technical guidance for enhancing the fire safety performance of steel structures, with significant implications for engineering applications.

Keywords: Steel Structure Fireproof Coating; Fire Environment; Performance Degradation Law; Nano-Enhanced Material; Thermal Decomposition Behavior

第1章绪论 1

1.1 钢结构防火涂料研究背景与意义 1

1.2 国内外研究现状分析 1

1.3 本文研究方法与技术路线 2

第2章火灾条件下钢结构防火涂料性能退化机理 3

2.1 防火涂料的组成与功能特性 3

2.2 火灾对涂料性能的影响机制 3

2.3 涂料性能退化的关键因素分析 4

第3章钢结构防火涂料在火灾中的热力学行为研究 6

3.1 火灾环境下的温度场分布特征 6

3.2 涂料热传导性能的动态变化规律 6