Recorcinol is the glue used commercially but you would not need a waterproof glue being under the house I guess so I would use PVA but the bolts as well ??? Dunno. Sounds as though you are spanning maybe 3 meters or so in which case more than 120mm would be the go .
I've just become an optimist . Iv'e made a 25 year plan -oopps I've had a few birthdays - better make that a 20 year plan