双空间钢构架混凝土组合柱复合受扭性能试验研究

Experimental study on combined torsional behavior of double spatial steel frame concrete composite columns

双空间钢构架混凝土柱是在空间钢构架混凝土柱中内埋空间钢构架所形成的组合柱,是一种新型的钢-混凝土组合柱。为了研究这种新型钢-混凝土组合柱在轴力、弯矩、剪力和扭矩复合作用下的受扭性能,以轴压比、内侧和外侧空间钢构架缀条的体积配箍率等为设计参数,进行6根双空间钢构架混凝土组合柱试件在轴力、弯矩、剪力和扭矩复合作用下的静力试验,对双空间钢构架混凝土柱在复合受扭作用下的破坏形态、开裂扭矩、扭矩-扭率曲线等受扭性能进行分析。结果表明,双空间钢构架混凝土组合柱具有较高的抗扭承载力和抗扭转能力。其他条件相同,双空间钢构架混凝土柱在复合受扭作用下承受的扭矩及相应的扭转角随着轴压比的增大而提高,随着内侧或外侧空间钢构架的体积配箍率的提高而增大。基于试验研究提出了双空间钢构架混凝土复合受扭柱的开裂扭矩的计算公式,可以用来预测试件的开裂扭矩。

Double spatial steel frame concrete column(DSSFCC)is a new type of steel-concrete composite column formed by buried spatial steel frame in spatial steel frame concrete column.In order to study the torsional behavior of this new steel-concrete composite column subjected to a combination of axial force,bending moment,shear force,and torsional moment,static test of six DSSFCC members under the combination of axial force,bending moment,shear force,and torsional moment is carried out.The effects of various parameters,i.e.,axial compression ratio and the volume hoop ratio of the inner and outer spatial steel frame,are considered respectively.The failure modes,cracking torque,torsional moment-torsion rate curves of DSSFCC members derived from the static tests are analyzed respectively.The experimental results show that double spatial steel-frame concrete composite column has higher torsional bearing capacity and torsion resistance.When other conditions remain the same,the torque and corresponding torsion angle of DSSFCC member increase with the increase of the axial compression ratio of composite column and the volume hoop ratio of inner or outer spatial steel frame.In addition,based on the experimental research,the formula for calculating the cracking torque of DSSFCC member is proposed,which can be used to accurately predict the cracking torque of the specimen.