Do concrete sidewalks need rebar?
Most sidewalks don't need to be reinforced with rebar.
The name comes from the term reinforcement bar and is typically used in thicker concrete sidewalks expected to support heavy trucks or machinery. Rebar might also be used in sidewalks required to withstand impact on a regular basis.
Sidewalks should be at least 4" (100mm) in thickness. Simple slabs for small foundations, bases, etc., normally 4" to 6" (100mm to150mm) thick, depending on the load they must bear. Slope the walk away from buildings to provide proper drainage.
Reinforcing concrete sidewalks with wire mesh helps to bridge over small imperfections in the subgrade. This lessens the likelihood that sinkholes will develop. Concrete sidewalks can be replaced in sections that mesh together nicely, although the color does not always match (few materials do).
Generally, a concrete walkway should be four inches thick for residential applications. The thickness is enough to prevent cracking under regular foot traffic and will last for decades. For areas with heavier traffic, such as a commercial or industrial space, the sidewalk should be 5-6 inches thick.
Reinforcing concrete with rebar or wire mesh not only makes the concrete strong, but it also significantly curtails the number of cracks that appear in that concrete down the line. This can save you money on repair work and keep your concrete aesthetically pleasing for years to come.
Without rebar reinforcement, concrete is highly prone to cracks due to tension forces. Rebar helps prevent cracks from growing wider largely by preventing cracked slabs from moving apart.
No, you do not need rebar for a 4-inch slab of concrete on grade. A 4-inch-thick slab cast on the ground and in permanent contact with it will float and rebar is not required. Rebar is recommended on concrete measuring 5 – 6 inches thick.
Concrete used for sidewalks shall be according to pertinent sections of Section 501 of the Standard Specifications for Air-Entrained, Grade A-2 Concrete. The foundation, forms and reinforcement, when required, shall be checked and approved by the Engineer before the concrete is placed.
All-Purpose Concrete Mix: When in doubt, all-purpose concrete mix is a popular option. This is ideal for repairing foundation walls, laying sidewalks, creating steps and setting posts.
- Stainless Steel Concrete Reinforcement. Stainless steel rebar is often touted as a replacement for standard steel rebar. ...
- Engineered Bamboo Reinforcement. ...
- Glass fiber reinforced polymer (GFRP) Rebar. ...
- Plastic Fiber. ...
- Helix Micro Rebar Concrete Reinforcement. ...
- Many Options.
Is wire mesh or rebar better for sidewalks?
Whether you're pouring a driveway, patio, sidewalk, or paved steps, it might be wise to use both materials. Deformed rebar offers strength and reinforcement, while the stainless steel mesh grid will provide shape and ensure the correct placement.
Plain cement concrete (PCC) is simply concrete by definition. It is cement + water + fine aggregates + coarse aggregates. It is the ordinary concrete without any kind of reinforcement.
In residential concrete, 4 inches is the minimum thickness for walkways and patios. Garage slabs and driveways should be 5 to 6 inches thick if any heavy truck traffic is anticipated, otherwise 4 inches is adequate.
For a long-lasting concrete sidewalk, plan on a 4-in. base of gravel under 4-in. of poured concrete. If you live in a frost-free climate with a natural sand base with good drainage, you can pour right on top of the sand.
Only after about 100 years and the complete corrosion of the zinc does the carbon rebar itself corrode and then lead to concrete failure. Because failure of the rebar leads to compromised or failing structural capacity, protecting against premature rebar failure is key.
Can You Use Rusty Rebar in Concrete? It's perfectly fine using “rusty” rebar that is coated in mill-scale and is not genuinely rusted. Mill-scale has even been shown to improve the adhesion between rebar and concrete.
Rebar can be stronger but might be considered overkill for projects While rebar is often stronger than wire mesh, you might find that the level of strength provided by rebar is overkill for most projects. Heavy-duty wire mesh can offer the required level of durability while limiting your costs considerably.
Why Do Builders Need an Underslab Vapor Barrier Plastic? An under-slab vapor barrier protects the subfloor and, subsequently, the main floor from moisture by adding a protective layer underneath the concrete foundation before it is poured on wet. Underneath every building, in the ground, is water.
Install reinforcement (optional) such as rebar and rewire set on bolsters (inset photo), and then mix and pour the concrete. The use of fiber-reinforced crack-resistant concrete eliminates the need for wire reinforcing mesh.
Popular Thickness
Most contractors pour a 4-inch thick slab for a pavement or walkway, creating a stable surface to accommodate foot traffic and light-wheeled vehicles such as motorcycles or hand carts. It is vital, robust, and water-resistant to properly cured concrete.
How far apart should sidewalk joints be?
Joints are commonly spaced at distances equal to 24 to 30 times the slab thickness. Joint spacing that is greater than 15 feet require the use of load transfer devices (dowels or diamond plates). Contraction joints may be tooled into the concrete surface at the time of placement.
Place rebar in a grid pattern with a spacing between bars of approximately 12 inches. In either case, blocks should be used under the reinforcement to keep centered within the concrete. Synthetic fibers have also proven to be beneficial in driveways as a way to reduce shrinkage cracks.
You want your concrete sidewalk to be at least 4 inches thick to ensure it's going to be durable and support all the weight that might be placed on it throughout its life. As long as you're ordering concrete, you're better off ordering more than you need than not ordering enough for your project.
Long story short, yes you can pour concrete over dirt. However, you need to follow the process outlined in this article for the best results. If this all seems a bit overwhelming, we suggest reaching out to a professional concrete contractor.
Concrete is one of the most economical, versatile and durable building materials available. Build a sidewalk, patio, or floor with QUIKRETE concrete mixes no matter your skill level.
Bottom line: Cement is a powdered ingredient used to make concrete. Concrete is the material used to make sidewalks, driveways and buildings. Sakrete makes a number of different concrete formulations in varying strengths and set times to meet the needs of different job requirements.
Concrete with a two thousand year lifespan. Roman concrete has mostly stood the test of time. The Pantheon for example was dedicated in 128 CE and has the world's largest unreinforced concrete dome.
| 40-pound bags | 80-pound bags | |
|---|---|---|
| 3 feet wide by 4 inches thick | 4 | 2 |
| 3 feet wide by 6 inches thick | 5 | 3 |
| 4 feet wide by 4 inches thick | 5 | 3 |
| 4 feet wide by 6 inches thick | 7 | 4 |
No, you do not need rebar for a 4-inch slab of concrete on grade. A 4-inch-thick slab cast on the ground and in permanent contact with it will float and rebar is not required. Rebar is recommended on concrete measuring 5 – 6 inches thick.
Concrete for sidewalk slabs must consist of 3500 to 4000 PSI, a combination of 3/4 blend of sand, stone and cement and also 6 to 7% air included in the mix. An expansion joint should be placed no less than approximately every 25 to 30 linear feet.
How long does rebar last in concrete?
Only after about 100 years and the complete corrosion of the zinc does the carbon rebar itself corrode and then lead to concrete failure. Because failure of the rebar leads to compromised or failing structural capacity, protecting against premature rebar failure is key.
Most concrete contractors want a mix of coarse and fine aggregate to create a compactable base that is going to be safe for settlement and drainage. Crusher run (a mix of crushed stone and stone dust) and #57 coarse aggregate are two of the best base materials for concrete slabs.
Rebar should be placed evenly throughout the project. For a flat slab, such as a driveway, consider placing the rebar in an 18 inch grid spacing, keeping the edge rebar at the same distance from each side. For a patio you can use a grid spacing of 24 inches.
Materials such as chicken wire, stucco mesh, wire screening, expanded metal, fence wire or fiberglass cloth should never be used as primary reinforcement because their properties are too variable or they are not sufficiently strong. You cannot rely on these materials.
Cracks after hardening
More often, they result from poor curing. Other cracks which occur after hardening can be caused by lack of adequate reinforcement at corners, insufficient depth of concrete over bends in reinforcement, nesting of reinforcing steel in concrete, lack of expansion and contraction joints.
Any concrete that supports a heavy load should be reinforced. However, not all concrete structures need that kind of support. A small garden pathway or a pad under a playhouse probably won't require reinforcement.
Dirk Hebel Bamboo strips are tested for strength and resistance to tensile forces. Using WSB to reinforce concrete has many advantages. Bamboo is rapidly renewable and sequesters carbon, as opposed to the energy- and carbon-intensive steel.
Wire mesh is comparatively affordable than rebar. They come in rolls and are made using thin steel bars.
Another choice is materials that combine a polymer matrix with glass, carbon, or basalt fibers embedded—fiber-reinforced polymer (FRP). These materials can't corrode, they are much lighter than steel (about one-third the weight), they don't get hot in the sun on the jobsite, and they are 4.5 times stronger in tension.
