This report outlines the findings of two independent studies by PTL Structural Consultants (PTL) and Holmes Consulting LP
(HCLP) which have validated the use of an earthquake induced lateral force distribution, develop by Dr D.
Gardiner (at University of Canterbury). The method for determining the lateral force distribution for
designing the diaphragms of buildings is known as “the pseudo-Equivalent Static Analysis (pESA)”.

Principal Investigator: Des Bull