This paper presents a numerical investigation of the fire performance of eight reinforced concrete two-way slabs subjected to different in-plane restraints. A comparison of the experimental results with results predicted by a numerical model showed generally satisfactory agreement. The effects of geometric nonlinearity, or linearity, and concrete thermal strain on the fire behaviour of the tested slabs were analysed. It was found that neglecting the geometric nonlinearity led to lower predicted deflections for in-plane restrained slabs and higher predicted deflections for simply supported slabs, while a larger concrete thermal strain led to larger deflections for the concrete slabs under either restraint condition. Parametric studies were conducted to investigate the influence of in-plane restraint type, restraint level, aspect ratio, reinforcement ratio and layout, and slab thickness on the fire behaviour of the in-plane restrained slabs. The results of the parametric studies showed that the in-plane restraint type, restraint level, and aspect ratio significantly affect the deflection trends, failure mode, and fire resistance of in-plane restrained slabs. In addition, the fire-resistant performance for in-plane restrained rectangular slabs can be improved by increasing the reinforcement ratios along the short span.

本文给出了八种钢筋混凝土双向板在不同平面内约束下的防火性能的数值研究。实验结果与数值模型预测结果的比较表明，总体上令人满意。分析了几何非线性或线性以及混凝土热应变对试验板的火灾行为的影响。结果发现，忽略几何非线性会导致平面内约束平板的预计挠度较低，而简单支撑平板的预期挠度较高，而较大的混凝土热应变会导致在两种约束条件下混凝土平板的挠度较大。进行了参数研究，以研究平面约束类型，约束水平，长宽比，配筋率和布局，以及板厚对面内约束板的着火性能的影响。参数研究的结果表明，平面内约束板的类型，约束水平和纵横比会显着影响平面内约束板的挠度趋势，破坏模式和耐火性。另外，通过增加短跨度的增强比，可以提高面内约束矩形板的耐火性能。