From: Jim Kestner <jkestner(--nospam--at)somervilleinc.com>
Date: Wed, 28 Jun 2000 13:52:11 -0500
It certainly appears that the spacing of your joints should have been
adequate to prevent cracking between joints. Without knowing all the
specifics, I can only suggest some possible causes to look
Were the sawcuts deep enough? 1/4 of the slab thickness is recommended
although 1/3 is better as long as shear transfer can be maintained.
Was the slab reinforcement lapped at or near the joint?
Are there thickened slab footings in the area that may have restrained
the slab shrinkage?
Was the joint design or construction such that the joint was only
partially effective in relieving the shrinkage stresses?
Jim Kestner, P.E.
Green Bay, Wi.