钢管混凝土柱脚是连接上部结构与基础的重要节点，抗震性能优越的埋入式圆钢管混凝土柱脚在工程中得到大量应用。高层和大跨结构中，大直径钢管混凝土柱显著增加了柱脚埋深，致使柱脚施工难度加大，基础造价提高。同时现有规范设计方法比较笼统，导致不同参数下柱脚节点安全系数差别巨大。针对圆钢管混凝土柱脚埋深过大的缺点和现有设计方法的不足，本项目提出一种设置型钢短梁的埋入式圆钢管混凝土柱脚节点，能在有效锚固钢管混凝土柱的基础上显著降低柱脚埋深。本项目将对传统柱脚节点和新型柱脚节点进行系统的理论分析与试验研究，进行竖向荷载下钢管混凝土柱脚传力机理与抗冲切性能研究，进行柱脚节点在轴力、弯矩和剪力共同作用下的静力与抗震性能研究；通过研究确定柱脚的合理埋置深度，提出考虑多种因素影响的埋入式圆钢管混凝土柱脚抗冲切设计方法，提出柱脚在拉、弯、剪和压、弯、剪复杂受力状态下的设计方法，为相关规范制定提供参考和借鉴。

Concrete-filled steel tubular (CFST) column base is an important connection between superstructure and foundation. Embedded circular CFST column base has good earthquake resistance, thus it is widely used in the buildings. But with the increase of height or span of structures, large diameter composite columns are applied to resist the load. Thus the requirement of embedded depth of steel tube is obviously increased, which brings great difficulties to the excavation and construction of the foundation. Meanwhile, the existing design methods about the CFST column base are relatively brief, and the safety factor of CFST column base varies greatly for different parametric columns. To overcome the weak points of deeply embedded base and the deficiency of the existing design method, a new type of embedded circular CFST column base is proposed, which is embedded circular CFST column base stiffened with short steel beams. This new CFST column base can significantly reduce the embedded depth of column base on the basis of the effective anchorage of CFST column. In this project, the theoretical and experimental study of traditional CFST column base and the new CFST column base will be carried out. The punching behavior of column base under vertical load will be studied. And the static and seismic behavior of column base under axial load, shear combined with bending moment will be studied. Based on the study, the calculation method of punching bearing capacity of embedded CFST column base will be proposed, which can consider the influence of cohesion between steel tube and concrete, shear contribution of headed studs and short steel beam. The simplified design method of column base under axial load, bending moment and shear will be suggested. The research work can provide some useful references for the revision of design codes.