简支梁板中碳纤维筋极限应力增量研究

Research on ultimate stress increment in CFRP tendons for simply supported beams and slabs

利用无黏结CFRP筋部分预应力混凝土简支梁板全过程分析程序计算无黏结CFRP筋极限应力增量,考察CFRP筋弹性模量、预应力筋配筋指标、非预应力筋配筋指标、加载方式、跨高比和无黏结CFRP筋布筋形式等参数对简支梁板中无黏结CFRP筋极限应力增量的影响规律,从而确定影响无黏结CFRP筋极限应力增量的关键参数。基于仿真分析结果,以关键参数为自变量建立了简支梁板中无黏结CFRP筋极限应力增量的计算公式,可以此为依据计算简支梁板的受弯承载力。

Ultimate stress increment of unbonded CFRP tendon was calculated by full-range analysis programs of concrete simply supported beams and slabs partially prestressed with unbonded CFRP tendons.The basic factors such as modulus of elasticity for CFRP tendon, prestressing reinforcement index, non-prestressed reinforcement index, loading type, ratio of span to depth and profile of tendons affecting the law of ultimate stress increment of unbonded CFRP tendons were presented.Key factors which had major affect on ultimate stress increment of unbonded CFRP tendons were defined.Based on the results of simulations analysis, making key parameters as independent variable, the calculation formulas of ultimate stress increment of unbonded CFRP tendons in simply supported beams and slabs were proposed, and they can provide the basis for correctly calculating flexural load bearing capacity of beams and slabs.