So when it comes to the actual thickness of a concrete foundation wall, the rule of thumb is a minimum of 8 inches, and then 10 inches thick for walls taller than 8 feet. This should allow for higher PSI as well (pounds per square inch), which should be between 2,500 and 3,000 in residential construction.
As a practical consideration, residential designers need to keep in mind that concrete foundation walls are typically 6, 8 or 10 inches thick (nominal).
Concrete surfaces that support large trucks, heavy machinery, or steady traffic need concrete rebar reinforcement, and any structural concrete, like walls in buildings, should definitely include rebar.
The concrete core may vary from 140 mm to over 300 mm depending upon the structural design, while the two leaves of insulation may vary from 100 mm to 300 mm depending on the thermal insulation specification. Consequently, total wall thickness may be between 250 mm and 600 mm.
A 2-inch concrete thickness is generally not sufficient for a driveway that will be subjected to regular vehicle traffic. While it may be suitable for light-duty applications like footpaths or patios, a driveway requires a thicker concrete slab to withstand the weight and impact of vehicles.
Sandwich Panel Thickness
An exterior wythe of concrete measuring around 75 mm (3”) thick (although it may be as thin as 2”) A layer of rigid foam insulation (typically extruded polystyrene) that is between 50-100 mm (2 – 4”) thick. A load-bearing interior wythe measuring between 125-250 mm (5-10”) thick.
According to the Concrete Block Association, loadbearing internal walls should have a minimum thickness of 90mm, although most construction projects use blocks that are 100mm thick because these are widely available.
A standard Core Drill Bit has a max drill depth of about 14”. Deep drilling requires core drill tubing. This tubing, typically has lengths of 48” and is threaded at each end. This allows us to drill to any depth with most standard diameters.
For flat slabs of concrete on the ground that are no more than four to five inches thick, rebar may not be necessary.
In general, shorter walls with stable soil conditions may not require a footing. However, taller walls or those built on less stable soil will almost always require a footing to ensure stability and prevent failure.
The outside surface of the block is the compression side of the wall. The inside surface is being stretched—this is the tension side of the wall. Concrete has very poor tensile strength, which is why cracks are appearing.
According to IS 456:2000, clause 32.1.
1) Minimum thickness of load bearing RCC wall should be 100 mm. 2) If the story height is equal to length of RCC wall, the percentage increase in strength is 10.
Poured Concrete Walls
Poured walls have no joints, which makes them stronger and easier to waterproof. Poured concrete foundation walls are arguably stronger than cinder block foundation walls.
Standard concrete floor slab thickness in residential construction is 4 inches. Five to six inches is recommended if the concrete will receive occasional heavy loads, such as motor homes or garbage trucks.
A typical foundation wall minimum thickness of eight inches applies to walls eight feet or less with no more than seven feet of soil pressing against it. Foundation walls taller than eight feet with more than seven feet of soil pressing against it requires a larger foundation wall 10 to 12 inches in width.
Precast concrete can develop cracks due to tension, environmental factors like temperature and wind, as well as shrinkage during the curing process. Common types of precast concrete cracks include longitudinal hairline cracks, transverse cracks, diagonal cracks, random map cracking, corner cracks, and step cracks.
The fire-resistance rating of concrete masonry walls depends on the type of aggregate used in the units. A 2-hour rating can be achieved by a wall with an equivalent thickness of as little as 3 1/5 inches when expanded slag or pumice is used or 4 1/2 inches when siliceous gravel is used as the aggregate.
Undoubtedly, poured walls are a lot stronger than cinder block walls. They don't have joints like the ones found between blocks. The only joint found in poured concrete basements is the cove joint. This is where the floor meets the wall and sits on top of the footing.
Base thickness = 1/8 of the height of the wall but not less than 12 inches. Stem thickness = 6 inches + ¼ inch for each foot of wall height.
Single skin walls up to 450mm high can generally be built without piers but over that height piers are needed at 3m intervals. The strength and effectiveness of the pier will be greatly improved if it is built as an integral part of the wall fully bonding the units together.
Although precast concrete offers a lot of versatility, it comes with its limitations in design. The size and shape of the precast concrete is limited by the size that can be transported and handled. Also, sometimes it can be difficult to get the molds required for custom designs.
The panels, typically 125mm to 150mm thick, are non-load bearing and can be flat or custom-made. A wide range of finishes and patterns are available.
Typically, concrete masonry units have nominal face dimensions of 8 in. (203 mm) by 16 in. (406 mm), available in nominal thicknesses of 4 , 6, 8, 10, and 12 in. (102, 152, 203, 254, and 305 mm).