How to Avoid Common Concrete Floor Slab Construction Errors

To minimize common errors in concrete floor slab construction, several steps should be taken, including perfect base preparation, mix design, placement, finishing, and curing.

1. In residential construction, the typical thickness of a concrete floor slab should be 4 inches. If the concrete must withstand irregular extreme loads, such as motor homes or garbage trucks, the thickness should be five to six inches.
2. To lay the foundation, the ground level should be dug to the exact depth required to accommodate the slab thickness. Remove all organic matter and large hard objects such as stones and tree roots to a depth of at least 4 inches. If the grade must be developed, use gravel or sandy soil and compress the final base with a vibratory plate or equivalent device.
3. The edge is constructed from any straight material that can be fixed into place. If straight lumber is constantly unavailable, plastic or metal forms should be used. Prior to laying the formwork, install a string line with grade stakes or batter boards to provide a square, level reference.
4. The concrete mix should meet the compressive strength requirements (typically 3000 pounds per square inch) while avoiding measures that cause extreme shrinkage. Because the presence of water increases shrinkage and cracking, a plasticizer should be used to achieve the required slump.
5. Provide fibers to prevent plastic shrinkage cracking as well. For exterior slabs exposed to freezing weather or deicing chemicals, greater strength and entrained air are required.
6. It is recommended that no more than 1 to 2 gallons of water per cubic yard be added on the job site. If an extra slump is required, seek advice from the mixer truck driver on the amount of water to be included without causing the concrete to fail.
7. Spread the concrete as close to its final position as possible across the slab area, then rake it into place. Low-slump mixes can be hardened manually with a vibrator or with a vibratory screed. Complete with the least amount of force and float strokes required to achieve a smooth surface.
8. By pushing a 1-inch deep grooving tool into the surface, create control joints no more than 24 to 30 times the slab thickness and no more than 15 feet along both the width and length of the slab.
9. To keep joint spacings greater than 15 feet, various types of load transfer devices, such as dowels or dowel plates, should be used. Steel reinforcement is appropriate for slabs with large joint spacing or no joints.
10. It will increase the likelihood of random cracking while also keeping cracks firmly in place to maintain superior structural performance.
11. When the finished surface can withstand damage, the curing process should begin. It is not acceptable to allow the concrete to freeze or dry out. Apply a curing compound to the surface or use proper moist curing.
12. If the slab freezes, it should be wrapped in an insulator, such as insulating blankets or a 4-inch-thick layer of straw that is weighted down so it doesn’t blow away. Install the insulator unless the concrete has a minimum strength of 500 psi. It usually occurs within a few days.

Common Errors During Concrete Construction at Floor Slab

Floor Slab Thickness

The typical floor slab thickness in any residential construction should be 4 inches. If the load is heavier, five to six inches should be retained.

Ground Floor Slab Construction

• To create the foundation, cut the ground level to the appropriate depth to adjust the concrete slab thickness. Remove all organic material and large hard objects such as stones and tree roots to a depth of at least 4 inches.
• Use gravel or sandy soil to build the grade, and compact the final base with a vibratory plate or equivalent device. Any straight material that should be fixed into position should be included in the edge forms.
• If straight lumber is not available, plastic or metal forms can be used in their place. To maintain a square, level reference, a string line should be set with grade stakes or batter boards before arranging the formwork.

Concrete Mix For Floor Slab

• The compressive strength requirements for the floor slab should be met by the concrete mix. A plasticizer should be used because water causes shrinkage and cracking. To avoid plastic shrinkage cracking, use fibers. Maintain greater strength and entrained air for exterior slabs exposed to freezing weather or deicing chemicals.
• Avoid using more than 1 to 2 gallons of water per cubic yard on the jobsite.
• Rake the concrete into position around the slab area as close to its final position as possible. A handheld vibrator or a vibratory screed should be used to consolidate low-slump mixes.
• By pushing a 1-inch deep grooving tool into the surface, the control joints should be formed no more than 24 to 30 times the slab thickness and no more than 15 feet along both the width and length of the slab.
• Dowels or dowel plates should be used if the joint spacing exceeds 15 feet. Steel reinforcement is required for slabs with large joint spacing or no joints.

Curing Concrete Floor Slab

• Once the finished surface can control the damage, the curing conditions and method should be established.
• A curing compound should be applied to the surface, or moist curing should be maintained.
• In the event that the slab freezes, it should be wrapped in an insulator, such as an insulating blanket or a 4-inch-thick layer of straw that is weighted down so that it does not wipe out.
• Unless the concrete reaches a minimum strength of 500 psi, the insulator should be kept in place. It usually occurs within a few days.

FAQ’S

What can go wrong with concrete?

Construction errors such as adding insufficient water to the concrete mix, inadequate consolidation, and improper curing can cause distress and deterioration of the concrete. To avoid construction errors, proper mix design, placement, and curing of the concrete, as well as an experienced contractor, are required.

What are the precautions for placing concrete?

Wear alkali-resistant gloves, long sleeves, and long pants to cover your skin, waterproof boots, and eye protection to protect your skin and eyes. It is good practice to keep extra gloves and safety glasses at construction sites. When wet concrete comes into contact with the skin, it can cause severe chemical burns.