CSE 212: THEORY OF STRUCTURES II LECTURE 5: MOMENT DISTRIBUTION METHOD LECTURER: DR. B. OMONDI SECOND SEMESTER: 2018/2019 1 MOMENT DISTRIBUTION METHOD Introduction The moment distribution method is a structural analysis method for statically indeterminate beams and frames developed by Hardy Cross in 1932. The method only accounts for flexural effects and ignores axial and shear effects. From the 1930s until when computers began to be widely used in the design and analysis of structures, the moment distribution method was the most widely used method in practice. In order to apply the moment distribution method to analyze a structure, the following parameters must be established: a) Fixed end moments Fixed end moments (FEM’s) are the moments produced at member ends by external loads when the joints are fixed. A summary of FEM’s based on different applied loads is given in Table 1. b) Member stiffness Factor (K) The member stiffness factor, K, of a member is represented as the product of the modulus of elasticity (E) and the second moment of area (I) divided by the length (L) of the member. When determining the stiffness of a beam at supports, the following factors should be noted:  Far-end member pinned or roller end support:     Internal members and far-end member fixed at end support:    c) Distribution Factors (DF) Distribution factor is the ratio according to which an externally applied unbalanced moment M at a joint is apportioned to the various members meeting at the joint. It is determined as:    ∑ . It should be noted that for fixed end support K = 0 and for pin or roller end support K = 1