外露式钢柱脚节点的抗剪性能

参考实际工程中使用的外露式钢柱脚节点，以柱脚底板孔径、柱脚底板厚度、锚栓直径和锚栓强度为主要参数，设计7组共19个大直径锚栓的钢柱脚试件，开展抗剪性能试验研究. 试验表明，锚栓连接具有可观的抗剪能力，节点的最终破坏模式有3种：当基础混凝土配筋足够时为锚栓剪断，配筋不够时为混凝土冲切破坏，介于两者之间的锚栓剪断同时存在混凝土冲切裂缝；锚栓连接的荷载-相对位移曲线呈现2种类型，主要区别在于是否存在滑移段. 对于锚栓连接的抗剪承载力设计值，将 3个已有理论模型与试验结果对比，给出推荐的简化公式. 对于锚栓连接的极限抗剪承载力，提出考虑锚栓截面拉力、剪力和弯矩影响的计算模型.

Shear behavior of exposed steel column base joint

Totally 19 specimens in 7 groups with large diameters were tested to analyze the shear behavior referring to the exposed steel column bases joint used in the practical engineering. The diameter of the hole of base plate, the thickness of base plate, the diameter of anchor bolts and the yield strength of bolt material were changed among the specimens. The test results show that the anchor bolt connection has considerable shear resistance. There are three ultimate failure modes: shear failure of anchor bolt when reinforcement of concrete is sufficient, punching failure of concrete when reinforcement of concrete is insufficient, or shear failure of anchor bolt and punching failure of concrete occur simultaneously. There are two types of load-relative displacement curves for anchor bolt connections, and the main difference is whether there is a slip section. The experimental values were compared with three existing theoretical models for the design shear bearing capacity of anchor bolt connection, and the recommended simplified formula was given. A model considering the effects of tensile force, shear force and bending moment of anchor bolt section was proposed for the ultimate shear bearing capacity of anchor bolt connection.