rubble

/ˈrʌbəl/
noun
  1. Broken pieces of stone, brick, concrete, or other building materials, especially after a building has been destroyed or damaged.
    • The old factory was demolished, leaving a pile of rubble on the site.
    • Children played in the rubble of the abandoned house, picking up interesting rocks.
    • After the earthquake, rescue workers searched through the rubble for survivors.
  2. Rough, irregular pieces of broken rock used in construction, such as for filling or making foundations.
    • The road was built on a base of compacted rubble and gravel.
    • A layer of rubble was spread at the bottom of the garden wall to improve drainage.
    • The builders used rubble to fill the trench before laying the concrete slab.