Control joints are weakened lines cut into concrete slabs to prevent cracking. When the concrete shrinks or expands, these control joints redirect stress away from the surrounding slab material, controlling the cracking location. 

On the other hand, expansion joints are cut into concrete slabs after they have already been poured and cured but before they’ve cooled completely. These joints allow further flexibility and movement within the structure without compromising its integrity. They’re ideal for highways and slabs prone to shifting due to changes in temperature or stress.

A concrete grinder typically consists of diamond-tipped blades embedded in a metal disc that spins at high speeds. As these blades come into contact with the concrete surface, they cut away small amounts of material to produce an even, smooth finish.

Safety is one of the main considerations when planning to use core drilling for concrete cutting. Some precautions that your service provider should follow to minimise and prevent injury include:

• Wearing appropriate safety equipment, such as protective eyewear, gloves, long pants & closed-toe shoes
• Always having a backup plan in case things go wrong or if they encounter unexpected problems during the process, such as having alternative tools on hand
• Being aware of their surroundings at all times & taking extra care when working close to electrical lines or other potentially hazardous areas
• Following all safety guidelines established by the local government or construction regulatory body, including using barricades, detour signs or flagmen to prevent accidents in high-traffic areas