text: when is it important to provide a longitudinal joint in a rigid pavement (a case of parking facility)? this particular parking facility is about 200m*100m it is important for a few reasons.   thermal expansion--temperature changes cause the metal to expand and contract.--without the joint the concrete would crack.  building settlement.   with a parking garage, there is a lot of weight coming on and off during the day and night.   it is a much heavier building when it is full of cars.  this causes a sponge effect with the ground.   the joint acts as a sort of shock absorber.