What are the shortcomings of grillage analysis which is commonly used in structural analysis of bridges?

What   are   the   shortcomings   of   grillage   analysis   which   is   commonly   used   in structural analysis of bridges?
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1 Answer

Answer :

Grillage analysis suffers from the following shortcomings based on E. C. Hambly:
(i) For coarse mesh, torques may not be identical in orthogonal directions. Similarly, twists may differ in orthogonal directions.
(ii) Moment in any beams is mainly proportional to its curvature only. However, moment in an element depends on the curvatures in the beam’s direction and its orthogonal direction.
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