When the slab is loaded and force applied to it,
the top of the slab directly under the load will be put in compression.
However at the bottom of the slab. the concrete will pull itself in tension.
Put the ends of your fingers together than flex your wrist up.
You will feel the pressure at the top of your fingertips and
you will see a gap open at the bottom.
That is what is happening in a slab.
Concrete is strong in compression, poor in tension.
Rebar, or steel, is the opposite.
By combining the two, you develop a product that is superior
and complimentary to the strengths and weaknesses of the individual materials.
Two-way slabs are rectangular reinforced-concrete slabs that are supported on all sides. The reinforcement is placed perpendicular to the sides.
Flexicore is a specific type of precast concrete system, primarily used for flooring and roofing. It combines precast concrete slabs with hollow cores to reduce weight while maintaining strength. While all Flexicore products are precast concrete, not all precast concrete products are Flexicore, as precast concrete encompasses a broader range of components and applications.
A 4-inch concrete slab reinforced with rebar should be able to support a 13,000-pound trailer, provided it is properly designed and constructed. Factors such as the soil quality, the distribution of the trailer's weight, and the specific mix and placement of the concrete all play crucial roles in its load-bearing capacity. It's advisable to consult with a structural engineer to ensure that the slab meets local building codes and is suitable for this application.
bent and tied metal rebar for the slab-to-wall connection at all filled cells bent metal straps embedded into the lintel to connect roof to wall
all things that need to dry are based on 72 degrees concrete needs 30 days to fully cure.
Two-way slabs are rectangular reinforced-concrete slabs that are supported on all sides. The reinforcement is placed perpendicular to the sides.
Yes, if you are constructing this wall with concrete block you will need #5 rebar dowels stubbed out of the foundation at 32" on center. You will also need one #5 rebar running continues in the top course and fill all cells with dowels and top course with either structural grout or concrete.
When the slab is loaded and force applied to it, the top of the slab directly under the load will be put in compression. However at the bottom of the slab. the concrete will pull itself in tension. Put the ends of your fingers together than flex your wrist up. You will feel the pressure at the top of your fingertips and you will see a gap open at the bottom. That is what is happening in a slab. Concrete is strong in compression, poor in tension. Rebar, or steel, is the opposite. By combining the two, you develop a product that is superior and complimentary to the strengths and weaknesses of the individual materials.
Rebar is an informal term for steel "reinforcing bar". These are steel bars that are placed within the structure before the wet concrete is placed. Steel reinforcement is necessary for almost all structural concrete because concrete has virtually no tensile or shear strength. The rebar provides almost all of the resistance to tension and shear within the structure.
Rusty concrete is there such a thing? If the concrete is rusty because it was stained by steel laying on it, that will be easy. Clean the concrete with some muratic acid (follow the instructions on the jug), rinse it, then paint it with concrete paint. Your local hardware store can provide different colors and options depending on the product line(s) they carry. If your concrete is rusty because the rebar is rusting and the rust is bleeding through, you have a problem. You need to remove all of the spalling, loose, and unstable material from around the rebar and then patch the spot. You might be able to prep the area with a pressure washer or you might need a cold chisel. Rusting steel rebar destroys concrete because it swells and splits the concrete. The surface needs to be sound before you paint. Painting is easy, surface prep always takes the most time.
The amount of rebar depends on the thickness of what you are making. All three dimensions.
Although not all Jewish graves are covered by concrete slabs, Judaism has very strict rules regarding grave desecration so at the minimum, a tombstone must be erected. One law is that Jews are not supposed to walk on graves so many Jewish cemeteries use these slabs, or sometimes concrete curbs to clearly delineate the location of the grave.
If your peice of concrete does not have beams I consider that flatwork. So in flatwork with 3/8 rebar (#3) on 16" centers, for the 15 foot side you will have 8 pieces x 15' long. On the 10' side you will need 12 pieces x 10'. (6 bars cut in half) In all you will need 14 #3 x 20'
Structural slabs are typically elevated concrete slabs - 2nd floor, 3rd floor, roof, etc. These slabs will contain steel reinforcing (rebar) or post-tensioning (tendons). The steel provides strength to support loads, ductility to prevent sudden failure, control of movements/cracks (due to temperature changes (thermal expansion/contraction) and shrinkage stresses (which occur as concrete cures)). Slabs on grade are concrete slabs cast on the ground, usually over an aggregate base course. They may or may not contain rebar or tendons (sometimes they contain welded wire fabric) - these are all for movement/crack control, and may also be used where soil problems are anticipated (expansive soils). There is also something called a structural slab on grade (or structural slab over backfill). A common place to see these is on exterior slabs that occur over backfills adjacent to the basement of a building. This artificially compacted backfill will often settle, especially if exposed to water (even if properly compacted). If it is critical to limit settlement of a slab that is over backfill, the slab is usually designed and constructed as a structural concrete slab which spans across the backfill soil (and does not depend on support from the backfill soil). The slab will usually span from the basement wall (which it bears on or is connected to), over the backfill soil, and bear on native soil.
Until all the rebar is gone. Rebar is just low grade steel with next to nothing in it to prevent rust. After a surface coat of rust gets on it (2-3 days) it will slow the process but it will never stop. Rebar is normally set inside concrete which also slows down the rusting but if you break open any concrete slab with rebar in it you will see it has rusted. Better still, avoid the problem in the first place. If you don't want to see rust, don't use steel. use composite (FRP) rebar. this is manufactured from glass-fibre based composites and is used where steel can not or should not be used.
Mivan Technology involves columnless , beamless construction but usually all walls & slabs are of 150mm concrete and slabs as a whole. Pre-planning is required to leave openings for doors,window & services shafts in shuttering itself.
Flexicore is a specific type of precast concrete system, primarily used for flooring and roofing. It combines precast concrete slabs with hollow cores to reduce weight while maintaining strength. While all Flexicore products are precast concrete, not all precast concrete products are Flexicore, as precast concrete encompasses a broader range of components and applications.