You are quite correct csd72. I tried the method using the maximum moment under the point load and it worked. The only observation I made is that if the load is one third along the section the midspan moment can be estimated by
M = Mab - (2Ma + Mb)/L and not Mab - (2Ma + Mb)/2.
Thanks anyway...
The support moments of a continuous beam can be obtained using Clapeyrons Three-Moment Equation or Moment Distribution by Hardy Cross or other methods available. The mid-span moment of a section spanning between two supports a & b with uniformly distributed load can also be estimated using the...