To construct a retaining wall, you will need to understand its basic components. These are the Stem, the Construction joint, and the Base slab footing. Each has their own function and importance. It will be much easier to know how to properly install them. You can reach a professional if you have any questions.
Base slab footing
The base slab footing of a retaining wall is an integral part of the wall’s foundation. The footing is required to have a specific density and strength. A foundation drain should be installed around the perimeter of the footing. A drain should be made with gravel or crushed rock that contains at least 10% material that meets a No. 4 sieve. It should extend 12 inches beyond footing. The drain should be constructed so that the drain’s bottom is at least six inches below floor. It should be covered with approved filter membrane material.
The footings of a retaining wall should be built on top of an existing concrete slab. A concrete slab can shift the foundation and cause the wall’s collapse. Therefore, a trench should be dug around the base slab footing so that the retaining wall is supported by two layers of soil. The soil should be dug out at least two feet deep. The foundation must be protected from frost.
A retaining wall’s base slab should be cast at a depth between 1’6″ and 2’0″. The width of the foundation should be 24″ and the thickness of the concrete block footing should be at least nine inches. Clay foundations should have a depth of two feet. Concrete besser blocks adelaide columns should be used to anchor the foundation to the ground. If the foundation is made of cement, it should be supported by square footings with a thickness of 12 inches. The footings should have 1/2″ bars of 6 inches in diameter. The footings should also be reinforced with six-inch mesh.
After the shaft has been poured, pressure-injected footings must be poured 12 hours later. A suitable method of placing concrete should allow the contractor or design professional to measure the impact energy of each batch to ensure that the base footing is properly filled.
Shear key
The shear key for components of a retaining wall is a structural element that is installed into the footing of the retaining wall. The key needs to be strong enough to mobilize the passive soil pressure without yielding. It must move away from the soil on one end, and in a direction that does no cause tension. The shear key also needs to be designed for the lateral load applied to it.
Because they can counter lateral loads and preserve structural integrity, shear keys are essential components of retaining walls. They also help reinforce the bonding of old and new concrete. Shear keys also minimize sliding of the wall. They also increase the design moment and rotate the stem of a wall. However, shear keys used in footings must be strong enough to withstand higher forces and deformations.
Adding a shear key to components of a retaining wall can improve its passive and active pressure resistance and enhance its sliding resistance. Shear keys can be placed underneath the stem of the wall and are easier to insert from the stem. According to ACI 318-17, the depth and width of the shear key must be at least twice that of the stem.
In earthquake-prone areas, a shear key is a critical component of retaining walls. These keys are placed in the joint between footing and steel column. They are made from T and I-sections that are welded to the baseplate. They are very resistant to shearing forces.
Stem
A retaining wall is usually divided into segments. These segments represent material, thickness, reinforcement size, spacing, and other changes. The most common wall design includes two to three changes in stem. You can also place dowels into the stem. The dowels can be placed at the top of the stem or farther up the wall.
The stem is the portion of the wall that supports soil. It extends on both sides of the wall. The footing extends the wall base away the retained soil. It is designed to support soil weight and surcharge pressure. If the soil is not sufficiently compacted, the stem can be weakened, which leads to cracks.
A retaining wall should be designed to withstand sliding and turning. At least 1.5 should be the minimum safety factor against overturning. It should not exceed the allowable bearing pressure of the soil. Tables 1 and 2, Allowable Stress Design for Concrete Masonry, include recommended stem designs.
Another type of retaining wall is the cantilever. These walls are often made from reinforced concrete and are more economical than gravity walls. They can also be precast in a factory. Counterfort retaining walls can support up to 5m of backfill. For a higher level of soil, a cantilever retaining wall may be more appropriate.
Construction joint
The construction joint is the horizontal connection between the footing and the wall. It is usually discharged separately and includes a keyway, which increases the slip resistance of the wall. The joint runs the length of the wall and is continuous. Sometimes, a vertical construction joint may be required.
The construction joint is an important part of any retaining wall. It prevents excessive deformation of a structure. A joint is also a structural element that allows free moment between two structural elements that have different functions. The joint is a structural element that allows for free moment between two elements in a concrete structure. It separates large concrete masses and prevents them from deforming.
Concrete pours are not always done in one shot. If it does, it will need to be poured over previous pours. It is important to ensure that the joint is clean and free from any debris. You can clean the joint with hand-held tools, but if the joint becomes very hard, abrasive blasting may prove to be necessary.
It is important to remember when constructing retaining walls that a single batch of concrete will not be enough to support the entire structure’s weight. The walls are formed in several pours, each one a few feet thick, and they will be connected by construction joints. In addition, the joint at the base is difficult to avoid, and if it is chipped, it may not provide adequate strength.
It is important to make sure that the expansion joint of retaining walls is waterproof. This is especially important if the wall is built against the ground. Otherwise, the walls may fail due to cracking, settling, or even tilting. This failure indicates that the design of a retaining wall isn’t as robust as it could have been.
Segmental retaining wall units
Segmental retaining wall units are a popular option for a variety of applications. Unlike traditional retaining wall materials, they do not require any mortar or concrete footings and are easy to install. They are flexible and structurally sound. Their wide range of applications makes them the perfect choice for widening a slope or outdoor area. They are used often to widen driveways, pathways, or patios.
These soil parameters must be specified in the design documentation for these structures. This includes the soil classification, effective friction angle and compacted density. The soil should be porous enough to support a structural element such as a wall. It should also be flexible enough for changes to the project specifications.
Contractors should refer to the NCMA’s “Segmental retaining wall installation guide” to ensure proper installation. In addition to installing the units, they should place drainage fill between them. They should also place soil fill in uniform lifts across the embankment to ensure that the units are aligned.
To ensure that the segmental retaining wall unit is installed properly, the contractor should furnish all materials, labor, and equipment, as well as supervise the construction. The materials must be inspected upon delivery and stored properly. They should not be included in the segmental wall if they are missing or damaged. Contractors should also ensure that materials used in the construction of segmental wall units are high-quality and manufactured by licensed manufacturers.
The climate affects the durability of segmental retaining walls units. If the temperatures are consistently above the freezing point of water, they may be susceptible to freeze-thaw damage. It is important to test the freeze-thaw performance of a segmental retaining walls unit when it is exposed to freezing temperatures.
