已有梁腹贯穿横缝斜截面承载能力试验

Experiment on Diagonal Section Bearing Capacity of Existing Penetration Transverse Crack in Beam Web

针对已有梁腹贯穿横缝的特殊性,提出了横缝斜向起裂剪力和横缝斜截面抗剪能力计算公式,并将计算结果与试验结果进行了对比。结果表明:斜截面受剪破坏对梁横缝截面的剪切破坏起控制作用,斜截面抗弯对梁横缝截面的弯曲破坏起控制作用;出现斜裂缝后,受拉纵筋锚固不足或抗剪压混凝土面积过度削弱,都导致梁横缝截面抗弯能力降低;横缝斜向起裂剪力要低于完整梁截面。

Aimed at speciality of existing penetration transverse crack in beam web,the calculated formulas on diagonal section shear capacity and diagonal cracking shear force of transverse crack were proposed.The calculated results by the formulas were compared with the experimental results.The results show that the diagonal section shear failure and diagonal section flexural failure are the controlling modes for failure of transverse crack section.Once diagonal cracks appear,the flexural capacity can be degraded for insufficient anchorage or excessive reduced concrete areas due to shear and compression.The diagonal cracking shear force of transverse crack is lower than that of the intact beam sections.