Internal Force Evaluation of Portal Frame with Tapered Members

To obtain the accurate expression of the internal force of the single-span portal frame being composed of tapered members, the force method was used to solve internal force of the portal frame with both hinged ends in consideration of various possible loads in practical projects. Gauss numerical integration method was used to simplify the complex integration when the deformation energy was calculated. Under the precondition of satisfied accuracy, the explicit expression of horizontal reaction force was obtained. Furthermore, the bending moment, shear and axial force could be solved for arbitrary section of tapered members. The research work can be used as the reference for evaluation of portal frame members, the programming of portal frame design codes and the further optimization of members. Keywords: Tapered member; internal force evaluation; force method; numerical integration