A new methodology for determining redundant reactions of beams is presented in this paper. This methodology is based on the principle of quasi work, which is a powerful pseudoenergy theorem deduced from Tellegen's theorem. It takes topography of a structural system as a variable in addition to the variables involved in conventional energy methods, variational principles, and finite element methods. The concept of topologically similar system lies at the heart of the principle of quasi work. This concept is explored for beams to define topologically similar beams and topologically equivalent beams. The principle of quasi work is validated for beams and subsequently used for determining redundant reactions of indeterminate and continuous beams. Further, a unique concept of reference beam is developed. Equation of deflection curve of this reference beam is used to solve redundant reactions of indeterminate beams. This methodology has an advantage of calculating redundant reactions mostly by simple multiplications without any integrations or differentiations and does not require any prior knowledge of writing bending moment expressions. The method is illustrated through examples. It is possible to develop an interactive graphic computer package for calculating reactions of indeterminate beams. Nomenclature A n = cross-section area of beam represented by TSS n fdg n = displacement in TSS n corresponding to fPg m E n = Young's modulus of elasticity of beam represented by TSS n fFg m = internal forces in a TSS m L n = length of beam represented by TSS n M n = bending moment in the beam represented by TSS n M n = mapped bending moment in the beam represented by TSS n M = moment reaction on beam from support , in which represents A, B, C, etc. fPg m = external loads acting on TSS m R= reaction on beam from support , in which represents A, B, C, and 0, 1, 2, etc. U mn = quasi energy fFg T m fg n W mn = quasi energy fPg T m fdg n vx = beam deflection as a function of x w = intensity of uniformly distributed load x n = coordinate along longitudinal axis of beam represented by TSS n y = coordinate along the depth of beam measured from neutral axis fg n = deformation in TSS n corresponding to fFg m "x = strain as a function of x in the beam x = stress as a function of x in the beam = nondimensional parameter x n =L n m, n = subscripts 1,2,3, etc., representing different topologically similar systems hexp :i = if exp : 0 the value of the bracket 0;otherwise, it is equal to exp : fexp :g n = exp : is for TSS n