After the earthquake, the wreckage of buildings was scattered around the town.
The wreckage of the car remained at the accident scene.
Debris from the car was scattered around the accident scene.
The workers cleared away the wreckage of the collapsed building.
The wreckage of the sunken ship was found on the seabed.
The building was reduced to wreckage by the explosion.
がれき is the everyday word for rubble or debris, especially after a disaster, whereas 残骸 sounds a bit more formal or literary.
死骸 shares the kanji 骸 with 残骸 but specifically means a dead body or corpse, not the wreckage of an object or structure.
supernova remnant; SNR
Compound of 残 (ざん, 'remain') and 骸 (がい, 'corpse' or 'remains'). The kanji 骸 originally refers to bones or a dead body, giving the word a nuance of lifeless remains.