My home is 60 years old and I am currently re-sealing my expansion joints with self-leveling sealant. This crack between the stairs (pier & beam foundation) and my walkway is a vertical crack as opposed to horizontal, thus I don't think the self-leveling will work. I got some mortar repair quikrete mortar repair caulk as it would hold it's position, but on the can it says don't use on expansion joints. My thought is this gap acts as an expansion joint, is that correct? What would be the proper material to use? Thanks for the help.