The reaction moment calculations of Hinged and Gimbal expansion joints, designed according to the “Standards of Expansion Joint Manufacturers Association” (EJMA), consider the bellows spring rate and pin friction. The reaction moment due to the lateral pressure forces should also be considered. Metal bellows subjected to angular movement extends one side and contracts the opposite, generating a lateral force caused by the media pressure.
This paper evaluates the lateral force reaction moment in a hinged expansion joint with the hardware designed for angular movements. For this purpose prototypes were built and the moments evaluated, simulating actual field conditions.