钢框架结构楼板有效宽度及对节点性能影响

Effective breadths of concrete slab and effect of slab on steel connections

为研究混凝土楼板对钢框架结构受力性能的影响,建立钢框架结构梁柱节点空间有限元模型.通过分析楼板对梁翼缘拉应力大小的影响,研究混凝土楼板对梁柱节点焊缝拉应力大小的影响及荷载大小对楼板有效宽度的影响.研究结果表明,相同弯矩荷载作用下,混凝土楼板无论是对梁上翼缘,还是对梁下翼缘节点焊缝开裂,都有一定的保护作用.当楼板受压时,随着弯矩的不断增大,楼板的有效宽度先是快速减小,然后缓慢减小.当楼板受拉时,随着弯矩的不断增大,楼板的有效宽度先是减小,然后增大.

To study the effect of concrete slabs on structural behaviors of steel frame structures, three - dimensional finite element models of beam-to-column joints were established. Based on analyses of effect of concrete slabs on the stress in beam flanges, the effect of concrete slabs on the fracture of beam-to-column joints was studied. The effect of loadings on the effective breadth of slabs was also studied. Results show that slabs have active effects on the failures of both the top beam flange and the bottom beam flange under the same moment load. The effective breadth of the concrete slab is relative to the loadings. If the concrete slab is in compres- sion, the effective breadth decreases rapidly with the increase of loading at first and then decreases slowly. If the concrete slab is in tension, the effective breadth decreases with the increase of loading at first and then increases with a slow rate.