吴 波, 乔长江. 混凝土约束梁升降温全过程的耐火性能试验[J]. 工程力学, 2011, 28(6): 88-095.
引用本文: 吴 波, 乔长江. 混凝土约束梁升降温全过程的耐火性能试验[J]. 工程力学, 2011, 28(6): 88-095.
WU Bo, QIAO Chang-jiang. EXPERIMENTAL STUDY ON FIRE BEHAVIORS OF RC RESTRAINED BEAMS DURING HEATING AND COOLING PHASES[J]. Engineering Mechanics, 2011, 28(6): 88-095.
Citation: WU Bo, QIAO Chang-jiang. EXPERIMENTAL STUDY ON FIRE BEHAVIORS OF RC RESTRAINED BEAMS DURING HEATING AND COOLING PHASES[J]. Engineering Mechanics, 2011, 28(6): 88-095.

混凝土约束梁升降温全过程的耐火性能试验

EXPERIMENTAL STUDY ON FIRE BEHAVIORS OF RC RESTRAINED BEAMS DURING HEATING AND COOLING PHASES

  • 摘要: 为揭示约束混凝土梁的升降温全过程火灾行为,开展了8根约束梁的明火试验,考察了升降温作用下梁端轴向和转动约束、荷载比、升温时间等参数对约束梁高温变形及内力的影响。试验结果表明:1) 升降温过程中试件轴力呈现出先较快增大而后逐渐减小并渐趋平缓的趋势,降温结束后仍存在明显的残余轴压力,试验过程中各试件的最大轴力比约0.05―0.1;2) 升温时间对试件左、右两端弯矩最大值的平均值影响有限,即该最大值的平均值基本上在升温60min内就已达到;3) 转动约束刚度比改变对试件左、右两端附加弯矩最大值的平均值影响不大。

     

    Abstract: In order to investigate the fire behaviors of reinforced concrete (RC) restrained beams during heating and cooling phases, eight restrained RC beams were tested in fire with a cooling phase. The influences of some parameters (such as axial/rotational restraint stiffness, load ratio, and heating time) on deformations and internal forces of the restrained beams were discussed. Test results show that: 1) the axial force in restrained beam subjected to heating and cooling processes increases first and then drops gradually; the residual axial force is significant after the cooling phase, and the maximum axial force ratios of the specimens are range from 0.05 to 0.1; 2) the influence of heating time on the mean value of maximum bending moments at the left and right beam ends is limited, implying that the mean value of maximum bending moments reaches within 60 min of heating; and 3) the change of rotational restraint stiffness has little effect on the mean value of maximum additional bending moments at the left and right beam ends.

     

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