Effect of flexible joints on the stability and large deflections of a triangular frame

An isosceles triangular frame with rotationally resistive joints under a tip load is studied. The large in-plane deformation elastica equations are formulated. A stability analysis shows that the frame can buckle symmetrically or asymmetrically. The post-buckling behavior showing limit load and hysteresis are obtained by shooting and homotopy numerical algorithms. The behavior of a frame with rigid joints is studied in detail. The effects of joint spring constant and base length are found.