冷弯薄壁C型钢托梁-加气混凝土板组合楼盖足尺耐火试验研究

发布时间：2018-02-16 02:25

本文关键词： 冷弯薄壁型钢组合楼盖玻镁板吊顶构造荷载水平足尺耐火试验耐火极限　出处：《建筑结构学报》2015年08期 　论文类型：期刊论文

【摘要】：提出一种由冷弯薄壁C型钢托梁-轻质配筋蒸压加气混凝土板(ALC板)组合楼盖,并设计完成了6片该类组合楼盖足尺模型耐火试验,考察了吊顶类型、填充层、荷载水平等因素对组合楼盖耐火性能的影响。研究结果表明:1)当组合楼盖空腔岩棉填充层不依靠吊顶板材即可固定于相邻托梁龙骨之间时,填充层对组合楼盖耐火起有利影响;带35 mm厚岩棉填充层的组合楼盖试件在2.0 k N/m2荷载水平下,耐火极限较类似构造的无填充层楼盖延长10.6%,达到83 min。2)组合楼盖耐火极限随荷载水平降低呈增大趋势,其中,采用双层防火石膏板吊顶的冷弯薄壁型钢组合楼盖试件,当荷载水平由5.0 k N/m2降至2.0 k N/m2时,耐火极限由65 min延长至75 min。3)组合楼盖的托梁龙骨受火屈曲破坏模式与楼盖荷载水平及吊顶构造无明显关联,表现为半波长为螺钉间距的跨中上翼缘高温畸变屈曲同时伴随相邻腹板、卷边高温局部屈曲破坏。4)玻镁板具有明显优于防火石膏板的耐火性能,空腔无填充层的单层15 mm玻镁板吊顶的组合楼盖试件在2.0 k N/m2荷载水平下,耐火极限达到84 min。组合楼盖试件均满足我国规范的多层民用建筑耐火极限要求。
[Abstract]:A kind of composite floor with cold-formed thin-walled C-shaped steel bracket and light reinforced autoclaved concrete slab (ALC slab) is proposed. Six full-scale model fire resistance tests of this kind of composite floor are designed and completed, and the type of ceiling and filling layer are investigated. The effect of load level on the fire resistance of composite floor is studied. The results show that when the rock wool filling layer of combined floor slab is fixed between adjacent joist keels without the ceiling plate, the filling layer will have a beneficial effect on the fire resistance of composite floor. Under 2.0 K / m ~ 2 load level, the fire resistance limit of composite floor with 35 mm thick rock wool filling layer is 10.6 longer than that of unfilled floor with similar structure, reaching 83 min. 2) the fire resistance limit of composite floor increases with the decrease of load level, among which, the fire resistance limit of composite floor increases with the decrease of load level. When the load level of cold-formed thin-walled steel composite floor with double-layer fire resistant gypsum board ceiling is reduced from 5.0 K / N / m 2 to 2.0 K N / m 2, There is no obvious correlation between the fire buckling failure mode of the bracket keel and the floor load level and the suspended roof structure, when the fire resistance limit is extended from 65 min to 75 min. 3). The high temperature distortion buckling of span upper flange with half wavelength of screw spacing is accompanied by adjacent web plate, and the crimping high temperature local buckling failure. 4) the glass magnesium plate is superior to the fire resistant gypsum board obviously. Under the loading level of 2.0 K / m ~ (2), the fire resistance limit of the composite floor specimens without filling layer is 84 min. The composite floor specimens all meet the fire resistance limit requirements of our country's code for multi-story civil buildings.
【作者单位】：东南大学混凝土与预应力混凝土教育部重点实验室;上海钢之杰钢结构建筑系统有限公司;
【基金】：国家科技支撑计划(2011BAJ08B04) 中国矿业大学土木工程环境灾变与结构可靠性江苏省重点实验室开放基金项目(JSKL2014K04)
【分类号】：TU398.9

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