# Characteristic Points and Continuous Beams

*In reinforced concrete design we often require to make calculations for the bending
moments in continuous beams; when the spans are equal the bending-moments at supports
have values which depend upon the position of the span and the number of supports,andd are given in the leading text-books. When the spans are not equal the procedure usually
recommended is to apply the Theorem of Three Moments for successive spans and to
solve the resulting simultaneous equations; such calculations are often very complicated although experience in application of this Theorem enables one of considerable saving in effort to be obtained. Even with these expedited calculations, however, the matter is one of considerable labour and many engineers find it
very troublesome to proceed; their difficulty is often a combination of the effect of complcated calculation and a distrust of long formule.
Ewart S. Andrews*