Concrete Cutting Techiques

Wire Sawing

Wire sawing is a technique that originated in quarries to extract stone. It has proven to be an ideal choice for removal of thick sections of concrete. A multi-strand cable with diamond segments is threaded through a series of pulleys and is continuously pulled through the concrete. Since virtually no concrete structure or cross-section is too large to cut, wire saws are used where other cutting methods are impractical. The only restriction is the lifting and removal specifications of the job. Wire sawing is ideal for removing large sections of heavily reinforced concrete, such as piers, towers and bridge sections, and cutting concrete in areas where work space is restricted.

A wire saw consists of a multi-strand cable with diamond segments that are threaded through a series of pulleys attached to a drive wheel that is powered by a hydraulic power unit. The combination of the spinning wire and constant pulling force cuts a path through the concrete and steel reinforcement. A typical wire diameter is 10 mm. Wire saws can cut in any orientation, vertical or horizontal. Because the length of wire can be made to virtually any length, the cutting depth is unlimited.

Wall Sawing

Wall sawing employs a circular blade on a track-mounted machine. The track is attached to vertical walls or steep inclines, or floors, that will not permit the use of flat saws. Wall or track sawing is typically specified to cut precise dimensional door, vent and window openings. Straight as well as bevel cuts are possible with the wall saw. The wall saw is also an excellent choice for creating precise openings in any concrete structure.

The diamond wall saw blade consists of a circular steel core with diamond segments attached to the periphery. The blade is mounted on the spindle of the wall saw. The spindle runs along the wall saw track that is typically bolted to the cutting surface. The power source for a wall saw system is either hydraulic, air or electric. Wall saw blades can range from 457 mm to 1.8 m in diameter and can cut up to 838 mm in depth.

Flat Sawing

Flat sawing is the most commonly used diamond cutting method. It is typically used to cut horizontal flat surfaces such as floors, bridge decks, and pavement. Also called slab saws, flat saws feature a diamond blade that is mounted on a walk-behind machine requiring only one operator. Flat saws are typically used to provide expansion joints, remove damaged pavement sections, clean and repair random cracks for repair, and remove concrete sections for demolition purposes.

As with the diamond wall saw blade, a flat saw blade consists of a circular steel core with diamond segments attached to the periphery. The blade is mounted vertically on the spindle of the flat saw. The flat saw is pushed or propelled along a flat surface while the diamond blade makes the vertical cut to the required depth. Flat saws are typically powered by gasoline or diesel engines, electric or hydraulic sources. Flat saw blades can range from 305 mm – 1.4 m in diameter and can cut up to 610 mm in depth.

Core Drilling

Core drilling techniques are used when precise, circular cuts are needed. Holes of almost any diameter are easily drilled to make openings for plumbing, electrical and HVAC installations. Core drilling is also commonly used to create holes for routing cables or placing anchoring bolts, installing load carrying devices or dowel bars, or for concrete sample analysis.

A core drill bit consists of a steel tube with diamond segments brazed or laser welded on the drilling end. The core bits are mounted on the rotating shaft of various types of drilling machines. Core drills can be operated in any orientation, vertical or horizontal. Core drill machines can be powered by electric, hydraulic or air power sources. Core drill bits can range in diameter from 13 – 1524 mm and drilling depths are virtually unlimited with the barrel extensions.