Research On The Idealized Force-deformation Curve Of The Beam-column Connection And Effective Length Coefficient Of The Column In Metal Structure

At present, in the case of major earthquakes, the concept design and construction measures are generally designed to meet the requirements of the third level of seismic resistance. In the evaluation criteria, only the overall story drift can serve as an indicator, while there is no specific quantitative index in component and joint level. With the rise of housing industry in China, the construction of low level total assembly type aluminum alloy villa which does not require field wet operation appeared. However, the beam-column connections are generally weaker than the usual rigid connection, and the standard only have rigid connection frame column calculation length coefficient table, the design and checking calculation of the frame column of the semi-rigid connection construction in the whole assembly type has met the barrier.In this paper, we start from the monotonic and cyclic loading of the steel used in our country, the theoretical model of the steel used in our country is chosen respectively. The hysteretic curves of the full welded beam-column connections are obtained by finite element analysis. It is proved that the constitutive relation of the circular composite harden model is more suitable for the constitutive relation curves of steel properties under the major earthquakes in China.Then the way to obtain the performance parameters of steel joints is introduced and some physical indicators of the ASCE41-13 performance parameters are converted into the Chinese units, six types of rigid beam-column connections of our country are selected to compare with ASCE41-13. Starting from the failure mode of extended end-plate and T steel beam-column connections, meanwhile, two kinds of beam-column connections in various failure modes of the yield moment, ultimate moment, the idealized Force-Deformation curve is obtained and compared with the test data. It is found that the performance parameters of the beam-column connections of ASCE41-13 are relatively conservative.Finally, based on the four basic hypotheses, and according to the relationship of the angle of the beam and the displacement equation with the stability function expression, it comes to column and beam end moment. According to the principle of unbalanced moment in the structure mechanics, the bending moment distribution of the beam is given. And then, according to the moment balance between joints and columns, a series of linear equations are obtained. An expression for calculating the length coefficient is obtained by the coefficient of the equation is zero when the structure is unstable, we can break the barriers of the design and calculation of the whole assembly building frame column.