METHODS OF DEMOLITION
Demolition methods include:
- Explosives
Explosives allow rapid and complete demolition where other methods may be dangerous or slow. This requires extensive use of the police to enforce exclusion zones as well as pre- and post-demolition structural inspections for a substantial radius
- Hand demolition
This method may be used for small-scale projects. It involves the progressive demolition of a structure using hand tools.
- Machine demolition
This is by far the most frequently-used method and reduces the need for people to work at height, or manual handling.
Common techniques include:
- Swinging ball: Heavy steel ball suspended from a crane jib.
- Wire rope: Can be used for demolishing parts of a structure.
- Pushing arm: A machine fitted with a hydraulic pushing arm. This is operationally limited by height, so a building should be reduced by other methods first
DEMOLITION PROCEDURES
General demolition procedures include:
- Site compound and security set-up.
- Intrusive pre-demolition surveys such as; asbestos survey, structural survey, hazardous materials surveys, etc.
- Isolation of utilities and removal of water and electricity meters.
- Disconnection of utilities.
- Removal of asbestos if present
- Soft strip – taking the structure back to construction materials including the removal of windows and door frames.
- Superstructure (roof, walls, frame, stairs, ramps) demolition with special measures as constraints demand, such as de-build or protection of adjacent structures.
- Slab and foundation demolition.
- Site finishes as required.
MATERIAL DISPOSAL
Buildings handed over for demolition generally contain hazardous waste, rubbish for landfill and recyclable material. Best practice post demolition is ensuring the optimum recycling chains are in place and all waste is disposed off properly. . Clients can assist by handing over empty buildings and finding new uses for furniture and equipment.
REFERENCES
- Bs 6187: 1982 Code of Practice for Demolition. (n.d.). B S I Standards.
- Demolition of a construction work Definition. (n.d.). Law Insider. Retrieved October 7, 2022, from https://www.lawinsider.com/dictionary/demolition-of-a-construction-work