Diamonds on the Job: Understanding Concrete Cutting
Thicker, stronger, and heavier than most materials, concrete requires skill, precision, special equipment, and serious safety measures to cut. Just about every construction or renovation job calls for concrete cutting in one form or another, usually by diamond-tipped blades of varying design. In this work, accuracy is key and safety is critical. Here are five things to know about the highly specialized service:
There are several types of concrete cutting to meet the unique demands of each job site. They include wall sawing, slab sawing, core drilling, wire sawing, and cutting expansion joints.
Wall sawing carves away flat sections of existing concrete walls, anywhere from inches to several feet in size. Precise lines for smaller cuts create access for pipes, ductwork, or ventilation, while larger cuts create openings for doors and windows, or open space for expansions or replacement of bowing walls.
Slab sawing, also called flat sawing, is similar to wall cutting, but uses a specialty saw that sits atop horizontal concrete slabs of flooring, bridges, or roads. A saw operator walks behind the blade as it cuts through concrete, at depths ranging from inches to many feet. Slab sawing delivers precise cuts with less vibration and mess than jackhammers generate, and can be used to install pipes or wiring, or to remove damaged concrete before repaving, for example.
Core drilling carves a perfect cylinder and removes it from a concrete structure, usually to allow installation of pipes, electrical wiring, vents, or drains, without disturbing or damaging the surrounding concrete. Diamond-tipped bits drill tunnels of varying size with minimal dust and disturbance. Drilling is also frequently used to break up large slabs of concrete for removal.
Expansion joints, or saw cuts, are made at intervals along large slabs of concrete to allow the pieces to expand and contract with changes in moisture and temperature without cracking. These cuts must be made soon after concrete has set, no more than 24 hours after it’s poured.
While it’s important to have the right blade for a given job, certain saws also require specific power sources, which may be hydraulic, diesel, or electric. Some jobs sites also will necessitate support equipment such as scaffolding or cranes.
Mistakes in concrete cutting are expensive and potentially dangerous. Correctly located, precise, even cuts are imperative when installing pipes, wiring, windows, and doors. Accuracy in cutting is often key to keeping buildings structurally sound.
Risks to concrete cutters are clear and constant, so great attention must be paid to safety training, equipment, and protocols. In addition to protecting saw operators and their teams, it’s important to consider the safety of other crews who are working a site simultaneously. Safely removing slabs without dropping or crushing them, particularly at height, can require additional planning and equipment.
While cutting concrete generates less mess than jackhammering, it does produce dust, which can contain large amounts of respirable crystalline silica (RCS). The airborne particles are hazardous when inhaled and can cause silicosis, a serious lung disease, so proper masking is necessary for cutters.
ODG’s affiliate, DrillCore, specializes in concrete cutting, drilling, and removal for new construction and renovation projects throughout Virginia and Maryland. With over 15 years of core drilling and sawing experience, DrillCore teams are staffed and trained to handle concrete jobs of any size, for a wide range of sectors, at any time, as they’re equipped to provide emergency services.
Partnering with general contractors, mechanical contractors, architects, and owners in the public and private sectors, DrillCore performs wall sawing, duct penetrations, dock openings, slab sawing, sanitary line installation, drainage, and other projects, indoors and out. They also offer demolition services including structural element removal.
Completed projects include a renovation of Virginia’s Fort Lee Barracks, which required the drilling of 3,000 cores throughout the flooring of three 100-room buildings. To meet the project’s schedule requirements, DrillCore ran five crews averaging 200 cores cut per day.
Another completed project called for core drilling to accommodate new pipes in a large water tank at Henrico County’s Wastewater Treatment Plant. The drilling was complicated, as the 20-inch-diameter cores were some 60 inches in length – the thickness of the tank’s walls. DrillCore made the cuts in increments, using wedges and anchors to remove the core in segments, safely and accurately completing the project without damage to the walls of the tank.
With years of experience serving many different sectors, DrillCore offers superior service to any construction job. Their commitment and attention to both safety and detail have made them leaders in the field of concrete cutting.