Engineered demolition techniques for dilapidated structures
1 Modern Demolition Techniques
· Hydralic Rock Breakers
· Diamond sawing and Drilling
· Silent expansive chemicals
· Controlled Demolition
· Hydralic Brusting / Spliting
· Thermal lancing
· Hydro demolition
· Robolic demolition
· Cor Drilling - uses diamond tipped bits with hydraulic/electric/pneumatic geode drill motors - maximum dia - 2000mm.
ü Wire Sawing : Ultimate Demolition Tool
In wire sawing a diamond beaded wire is reared around the RCC members, to be cut. The wire is rotated at a high speed (100Km/hr) by a special machine while constantly applying a pulling force. The diamond wire penetrates and cuts through the steel and concrete.
Water is used as a lubricating coolant. Wire sawing has limitations on the size of RCC member, to be cut. This technique is ideal for fast primary demolition.
ü Hand Sawing
Han sawing uses a light weight hand held machine, with diamond blade to cut RCC in any direction. By this technique, even over hand cutting is possible. Max. Depth of cut is 150mm.
ü Time : Diamond tools cut concrete fast, reducing down time which Leeds to early project completion.
ü Limensional Tolerance: Diamond cutting is precise and controlled, little or no patching s required.
ü Structural Integrity : Diamond cutting allows removal of large amounts of concrete without damaging, remaining or surrounding structures.
ü Noise , Dust and Debris: Diamond cutting is relatively quiet and virtually dust free concrete pieces can be cut to specified size for easy removal.
ü Limited Access: Diamond cutting techniques can e used in confined areas and arrows existing equipment
Creates enormous sresses within concrete, producing tensile cracking of concrete.
Hand Operated Machines
Crane Mounted machines
ü Special Machine
ü Robotic machine
Tools to be used for job on Haul
The following factors should determine the technique
ü Volume of concrete to be dismantled
ü Space available for walling
ü Risks involved
ü Acceptable noise and Vibration levels
Hand Held Machines
ü Electrically Operated
ü Battery operated
ü Multifunction - Drill, Chip, Hammer Drill
ü Energy Per Stroke
ü Material Removal Per minute
ü Tool Mount Type
ü Tool Life
ü Maintenance Cost
ü Safety Features
Advantages & Disadvantages of Hand Held Machines
Easy to Handle
Unskilled labour can be used
Ideal for dismantling small volumes
Ideal for short term jobs
Ideal for vibration less chipping.
Requires great inuscular power
Limited removal due to low hammer weight
Little impact from small diameter chisel
High labour cost
Harmful box due to vibrations.
Harmful to finger blood vessels
Danger from dust & falling debris