板柱节点配置型钢剪力架对受弯和直剪承载力的影响分析及设计改进  

Analysis of Influence of Shear Head on Flexural and Direct Shear Resistances in RC Slab-Column Structures and Design Modification

作　　者：杜旭 DU Xu(Shanghai Tongjian-Qianghua Architecture Design,Ltd.,Shanghai 200072,China)

机构地区：[1]上海同建强华建筑设计有限公司,上海200072

出　　处：《结构工程师》2022年第5期29-35,共7页Structural Engineers

基　　金：住房和城乡建设部课题(2020-K-132)。

摘　　要：钢筋混凝土板柱节点配置型钢剪力架可提高冲切抗力,同时也增强柱上板带支座负弯矩区的抗弯承载力。如不恰当处理,该增强效果将与“强柱弱梁”抗震设计原则矛盾。本文提出改变型钢的截面形式且尽量靠近板底布置,实现不影响型钢剪力架抗冲切性能且减小其对弯曲承载力贡献的目的。为定量分析,考虑柱距和覆土厚度两个参数,设计10种典型工况的地下车库板柱节点。计算表明,在满足抗冲切性能前提下,改进设计的型钢剪力架对抗弯承载力的贡献百分比平均为17%,而传统设计中该值为40%,改进后该贡献百分比显著降低。建议通过适当增配柱纵筋增大柱抗弯承载力,实现“强柱弱梁”。此外,还提出型钢剪力架可提高“板-柱界面”处板的直剪抗力的新认识,针对10种工况计算了型钢剪力架对直剪承载力的贡献。Shear head can improve the punching resistance of slab-column connections in reinforced concrete slab-column structures. Meanwhile,shear head can also enhance the flexural resistance in the negative moment zone of the slab-column connections. This leads to a conflict with the seismic design principle of“strong column-weak beam”if the enhance effect is not appropriately treated. In this regard,modification to the traditional design was proposed,i.e.,optimizing the form of shear heads and arranging them to the plate bottom as close as possible. By doing this,the punching resistance was maintained and the enhance effect to the flexural resistance was limited. For quantitative analysis,ten typical slab-column connections were designed for underground garages considering the variable parameters of column space and soil thickness.Results found that the enhance effect to flexural resistance was significantly reduced to 17% compared with that of 40% according to traditional design. In addition,shear head can contribute to the direct shear resistance at“slab-column interface”. This was quantitatively demonstrated on the basis of ten slab-column connections.

关 键 词：板柱结构 板柱节点 冲切破坏 型钢剪力架 设计方法 

分 类 号：TU312[建筑科学—结构工程]