- 1 What Stone goes under concrete slab?
- 2 How many inches of gravel do you need for a concrete slab?
- 3 What are the different sizes of crushed stone?
- 4 What size stone is used in concrete?
- 5 Should you put plastic under concrete?
- 6 Can I pour concrete directly on dirt?
- 7 How many bags of concrete do I need for a 10×20 slab?
- 8 Do you need rebar for 4 inch slab?
- 9 What is the best gravel to put under concrete?
- 10 What is #2 crushed stone?
- 11 What is the best size crushed stone for a driveway?
- 12 What is the cheapest type of gravel?
- 13 What is ASTM 33?
- 14 What are the 4 main types of aggregates?
- 15 What aggregates should be avoided when making concrete?
What Stone goes under concrete slab?
Adding crushed stone under your concrete slab will provide a level surface for your foundation. Simply pouring concrete onto the ground will expose it to elemental erosion that will cause cracking and sinking. Similarly, if there are roots or plants under your slab, they may rot and cause unevenness.
How many inches of gravel do you need for a concrete slab?
A hand tamper is sufficient for packing gravel, but a plate compactor makes the job much easier, especially when preparing a large area such as a patio. Excavate the soil to a depth of 8 inches, allowing 4 inches for the gravel base and 4 inches for the concrete slab.
What are the different sizes of crushed stone?
Crushed Stone Grades
- Crushed stone #5 – Sizes are from 1″ down to fine particles.
- Crushed stone #67 – Sizes from 3/4″ down to fine particles.
- Crushed stone #1 – Sizes are from 2″ to 4″.
- Crushed stone #8 – Sizes from 3/8″ to 1/2″.
- Crushed stone #3 –Sizes from 1/2″ to 2″.
- Crushed stone #10 (also called stone dust) – Screenings or dust.
What size stone is used in concrete?
Crushed stone #8 includes stone between 3/8” and ½”. This is the most common stone used for concrete mixes.
Should you put plastic under concrete?
Recently, though, research has shown that the old traditional layer of 6-mil Visqueen (polyethylene plastic) under the slab is seldom effective for two main reasons: Although it may seem water-tight, this grade of material allows a lot of water vapor to pass through.
Can I pour concrete directly on dirt?
Long story short, yes you can pour concrete over dirt.
How many bags of concrete do I need for a 10×20 slab?
A 60-pound bag yields. 017 cubic yards, and an 80-pound bag yields. 022 cubic yards. For a 10 x 10 slab, you would need 77 60-pound bags or 60 80-pound bags.
Do you need rebar for 4 inch slab?
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.
What is the best gravel to put under concrete?
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) is one of the best base materials for concrete flatwork.
What is #2 crushed stone?
#2 (2 1/2″) crushed stone is a combination of assorted sized material that ranges from 1 1/2″ through 2 1/2″ which has been crushed and compacted in size, then processed through a square screen 3″ in size.
What is the best size crushed stone for a driveway?
If you’re installing a crushed stone driveway, the surfacing material you choose will be the star of the show! Make sure that you pick crushed stone that is sized in a way that is safe for driving, promotes good drainage and looks fantastic. The most common sizes used for driveway surfacing are 3/8″, 5/8″ and 3/4″.
What is the cheapest type of gravel?
Gravel Cost Per Yard. Bulk gravel costs $15 to $75 per yard on average. Crushed concrete, sand and gravel mix, and crushed shells are the cheapest stones at $15 per yard. Crusher run, pea gravel, steel slag, and river rock typically cost $50 per yard or more.
What is ASTM 33?
Frequently referred to as washed concrete sand or manufactured sand, ASTM C33 refers to a type of sand that meets specific ASTM guidelines for concrete aggregates and/or the items that are added into the concrete in order to prepare it for use. C33 sand also specifies the grading of the aggregate materials.
What are the 4 main types of aggregates?
The Different Types Of Aggregate. The categories of aggregates include gravel, sand, recycled concrete, slag, topsoil, ballast, Type 1 MOT, and geosynthetic aggregates (synthetic products commonly used in civil engineering projects used to stabilise terrain).
What aggregates should be avoided when making concrete?
Aggregates to avoid include:
- Those that are friable or susceptible to being split.
- Those with significant quantities of soft and porous materials.
- Certain kinds of “chert,” since they may have very low resistance to weathering and can lead to surface defects, called popouts (Photos 2 and 3).