【摘要】 为解决大尺寸、大荷载、超限的地铁上盖单向板耐火极限难以判定的难题，依据钢筋混凝土单向板火灾下挠曲变形方程和截面内力平衡原理提出等厚度的单向板缩尺试验方法，并开展对比火灾试验验证。研究结果表明：试验过程中，足尺模型和缩尺模型的温度场和力学行为都保持一致性，最终二者的耐火极限相对误差为-4.7%,缩尺单向板的试验结果偏保守；单向板在火灾下的挠曲变形接近正弦半波函数；根据截面内力平衡原理揭示影响单向板耐火极限的关键因素底部纵向钢筋的温度。单向板缩尺模型耐火试验可以等效反映足尺模型的耐火极限。研究结果可为地铁上盖楼板耐火性能的评估和消防验收提供有效的测试方法。更多还原

【Abstract】 In order to solve the problem that it is difficult to determine the fire resistance limit of one-way slab over the subway with large size, large load and over-limit, a reduced-scale test method of one-way slabs with equal thickness was proposed based on the deflection deformation equation and the principle of sectional internal force balance of reinforced concrete one-way slabs under fire, and the comparative fire tests were carried out for verification.The results show that during the test process, the temperature fields and mechanical behavior of the full-scale model and the reduced-scale model are consistent.The relative error of fire resistance limit of the two is-4.7%,and the test results of the reduced-scale one-way slab are on the conservative side.The deflection deformation of one-way slabs under fire is close to a sine half-wave function.According to the principle of sectional internal force balance, it is revealed that the temperature of the bottom longitudinal reinforcement is the key factor affecting the fire resistance limit of one-way slabs.The fire resistance test of the reduced-scale one-way slab model can equivalently reflect the fire resistance limit of the full-scale model.The research results can provide an effective test method for evaluating the fire resistance performance and fire inspection acceptance of building slabs over subway.更多还原