摘要
为研究腹板开洞对负弯矩区组合梁受力性能的影响,对三根腹板开洞外挑组合梁和一根对比梁进行了试验研究,考虑是否开洞、洞口大小、洞口补强等参数的影响。试验结果表明:腹板开洞后,组合梁开裂荷载减小,且初始裂缝出现在洞口上方混凝土板中;洞口区域截面纵向应变分布不再满足平截面假定;组合梁最终表现为洞口上方混凝土板的剪切破坏,承载力降低;洞口补强可显著改善梁的受力性能,提高其承载力。
In order to study the effect of web openings on the behavior of composite beams under negative moment, three perforated and one unperforated cantilever composite beams were designed and tested. Several parameters such as the existence, the size and the reinforcement of the opening were studied. The experimental results indicated that when the composite beams under negative moment are perforated, the cracking load will decrease, the first crack will appear in the concrete slab upon the opening, the longitudinal strain will not distribute linearly along the height of the section any more and the composite beam will lose its bearing capacity due to the shear failure of the concrete slab upon the opening. The mechanical behavior of the composite beams can be improved significantly by using reinforcement plates around the opening.
出处
《结构工程师》
2008年第4期99-105,共7页
Structural Engineers
关键词
负弯矩区
腹板开洞
组合梁
试验研究
negative moment, web opening, composite beam, experimental study
