A connection assembly for connecting a bolt to a slab includes a first connection part and a second connection part. The first connection part and the second connection part may be capable of being assembled to the slab in a manner so as to sandwich the slab with a first clamping member of the first connection part and a second clamping member of the second connection part between two opposite surfaces of the slab. The first connection part and the second connection part may be connected in a manner such that a connection between a first hollow-tubular-connecting-structure of the first connection part and a second hollow-tubular-connecting-structure of the second connection part may be within a through-hole in the slab, which extends between the two opposite surfaces of the slab.