How do you get the lines in concrete?

If you're using concrete to make a sidewalk, the shrinking concrete will cause cracks to appear as it dries. To prevent sidewalks from cracking in random spots and breaking apart, builders make lines in sidewalks. Of course, they don't just call them lines. The technical term for sidewalk lines is contraction joints.

Why do people put lines in concrete?

Concrete lines are also called control joints or cuts. When contractors pour concrete, they include these lines in specific places to control and prevent cracks. As the concrete dries, shrinks, moves and bears weight, it can crack.

What are the lines in concrete called?

These joints are called EXPANSION or CONTROL joints and are designed to make sure as the soil shifts or moved under varying seasons the slab will not crack along the large flat portions. Many don't know that these expansion joints vary in design.

How many times do you float concrete?

Push the bull float in one direction only across the concrete, keeping its front edge slightly above the surface by raising or lowering the handle. Two or three times is enough. Don't overwork the concrete or you'll weaken it by drawing too much sand and cement to the surface.

How long after pouring concrete should you cut it?

Joints should be sawed as soon as the concrete can withstand the energy of sawing without raveling or dislodging aggregate particles. For most concrete work, cutting should take place within the first 6 to 18 hours and never beyond 24 hours.

Why are there lines in concrete?

When should I start watering my concrete?

Properly curing your concrete improves strength, durability, water tightness, and resistance for many years. The first 7 days after installation you should spray the slab with water 5-10 times per day, or as often as possible. Once the concrete is poured the curing process begins immediately.

Do you push or pull a concrete saw?

Always let the saw do the work; simply guide its direction, but don't push it down into the concrete. You only need a quarter-inch cut at this point, but if the saw bites in a bit deeper, that's fine too. This first guided cut will ensure you keep your cuts straight during the rest of the project.

How far apart should concrete joints be?

The following recommended tips should be observed: Maximum joint spacing should be 24 to 36 times the thickness of the slab. Joints should be spaced about 10 feet and a maximum of 15 feet. When using joint groove for contraction joints, the joint should be a minimum depth of 1/4 thickness of the slab.

How often do you need expansion joints in concrete?

Usually, expansion joints should be no farther apart than 2 to 3 times (in feet) the total width of the concrete (in inches). So for a 4 inch thick concrete slab, expansion joints should be no more than 8 to 12 feet apart.

How do you cut control joints in concrete?

Cut joints 25% of the depth of the slab. A 4" thick slab should have joints 1" deep. Groover tools cut joints in fresh concrete. Saw cutting cuts joints as soon as the concrete is hard enough that the edges abutting the cut don't chip from the saw blade.

How do you cut a trench in a concrete slab?

Cut the concrete as based on your guide cut, rotate the depth handle to lessen the blade sharpness if needed. Slowly push the saw forward until the first edge of the trench is cut. Raise the blade then pull the saw back to the end of the trench and cut the second edge similar to what you did with the first edge.

Should I wet concrete while curing?

ANSWER: Keeping concrete moist helps the curing process. Concrete hardens as a result of a chemical reaction, called hydration, between cement and water, not because it dries. The hardening, or curing, continues as long as moisture remains in the concrete.

Why do brooms finish concrete?

Sometimes called brushed concrete, a broom is used to create a slip-resistant texture on the surface of the concrete. Concrete finishers have been broom finishing for about as long as there has been concrete. Broom finished thin overlays add skid resistance and upgrade a deteriorating concrete surface.

How long do you wait to trowel concrete?

Allow all of the water to disappear before you do anything else. This can take 20 minutes or 4 hours depending on the temperature, humidity and how hard the wind is blowing. After the bleed water is all gone you can get out your steel finishing trowel and put on the final touches.

What happens if you don't put expansion joints in concrete?

Concrete expansion joints give the slabs just enough room to move which helps prevent cracks & buckling. Without these joints, even a little movement creates pressure and stress on the concrete. Eventually weak spots can crack or buckle.

Can you pour concrete without expansion joints?

Expansion joints are virtually never needed with interior slabs, because the concrete doesn't expand that much—it never gets that hot. Expansion joints in concrete pavement are also seldom needed, since the contraction joints open enough (from drying shrinkage) to account for temperature expansion.

How many bags of cement do I need for 12x12?

As per calculation, for a 12×12 slab at 4 inch thick, generally you will need approximately either 104 bags of 60lb or 80 bags of 80lb of premixed concrete, at 5 inches thick slab, either 131 bags of 60lb or 100 bags of 80lb premixed concrete are required, while at 6 inches thick slab, either 157 bags of 60lb or 121 ...

How long will a diamond blade last cutting concrete?

Diamond-edged blades.

They can last between 12 and 120 hours of continuous use, depending on the quality of the blade and material they're used to cut.

How do you cut concrete horizontally?

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. They can cut up to 24" in depth.