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对受偏心轴向荷载作用、分别填充普通混凝土和高强混凝土的细长型圆钢管柱进行24组防火试验。此试验是对Romero等人在2011年所做的中心荷载柱的试验结果的进一步探讨。此防火试验中的试验参数涵盖了混凝土标准强度(30MPa和90MPa)、填充类型(普通混凝土、钢筋混凝土和钢纤钢筋混凝土)、轴向荷载水平(20%和40%)和荷载偏心(20mm和50mm)。在固定的边界条件下对室内温度下相对长细比高于其他样本0.5的柱进行试验。研究这种内填混凝土组合件偏心荷载的影响。试验结果显示,与填充普通混凝土的柱相比,添加钢纤维并不能提高细长型柱在偏心荷载下的防火性能。然而,在混凝土柱中添加钢筋则可以提高防火性能。在中空圆钢管中填充混凝土可以提高其防火性能,钢管高强混凝土柱在承载力方面有更明显的提升。与欧洲规范4-1-2中的简易计算模型相比较,尽管此方法可用于偏心荷载作用下的柱,但在预测内填普通混凝土柱和钢纤维钢筋混凝土柱时仍会产生较大的误差。
Twenty-four fire tests were carried out on slender circular steel columns subjected to eccentric axial load and filled with normal concrete and high-strength concrete, respectively. This test is a further discussion of the experimental results of a central load column made by Romero et al. The test parameters in this fire test cover the standard strength of concrete (30 MPa and 90 MPa), filling type (normal concrete, reinforced concrete and steel fiber reinforced concrete), axial load levels (20% and 40%) and load eccentricity 50mm). Experiments were performed under fixed boundary conditions for columns with a relative slenderness ratio of 0.5 at room temperature. The effect of eccentric loads on this type of filled concrete assembly was investigated. Test results show that the addition of steel fibers does not improve the fire resistance of slender columns under eccentric load compared to columns filled with normal concrete. However, adding reinforcement to concrete columns improves fire performance. The filling of concrete in the hollow steel pipe can improve its fireproof performance, and the steel reinforced high-strength concrete column has a more obvious improvement in bearing capacity. Compared with the simplified calculation model in European Specification 4-1-2, although this method can be applied to columns under eccentric load, there is still a large error in predicting the filling of ordinary concrete columns and steel fiber reinforced concrete columns .