There are several great references on the mechanical effects on bus structures due to short circuit currents. These references are:
-C. H. Van Asperen, AIEE Toronto Section Meeting of November 5, 1922, "Mechanical Forces on Busbars Under Short-Circuit Conditions" This paper was awarded the "First Paper Prize" for the year ,1922, by the AIEE. The paper is technical in nature and also discusses the predictions of theory with labortory tests.
-Stanley C. Killian, Development and Research Engineer, Delta-Star Company. Electrical World Dec 12, 1942, "Mechanical Forces on Buses Due to Fault Currents"
-H. B. Dwight,Electrical World, Vol 70, September 15, 1917 page 522 "Repulsion Between Strap Conductors"
-C. W. Frick, GE Review, Vol 36, May 1933, page 232, "Electromagnetic Forces on Conductors With Bends, Short Lengths and Crossovers"
--H. B. Dwight, AIEE, presented at 36th Annual Convention, June 20, 1920, "Calculation of Magnetic Force on Disconnecting Switches"
-H. K. Porter Company, Inc., Bulletin 38-E, Section 1, Power Conductors-Technical Data Section. This bulleting contains references to many articles by S.C. Killian of Delta-Star Company.
-ITE Circuit Breaker Company, Bulletin No.2603-2A, "Electrical Buses and Bus Structures" by William Deans, Copyright 1959.This 47 page bulletin is probably the most comprehensive summary of the the preceeding references. This publication presents several nomograms useful for bus design and I find it most useful when evaluating the existing short circuit bracing on bus structures.
-Book by ALCOA, Alcoa Aluminum Bus Conductor Handbook,Copyright 1957. Chapter 6 "Short-Circuit Conditions" covers this topic and lists other references, some of those mention above and others.