Often an overlooked but essential component of landscaping is the construction and design of a retaining wall. These are built to ensure that dirt, sand, and especially rock remains in place. For lots built on any sort of slope, often a retaining wall of some kind is necessary for safety as well as city requirements. Made of brick, stone, cement, allen block and wood, they are frequently used to stabilize slopes and slants that are present in your yard. These structures may also be constructed to resist water pressure that could lead to erosion of soil otherwise. While they are seemingly are simple to design and construct, there is a method to building solid, reliable walls that should ideally be left to professionals. Click http://www.thehyperhouse.com/2012/04/making-a-retaining-wall.
Overview of the Science
In the beginning stages of building a retaining structure, it is important to consider the elements and possible problems that may arise depending on the wall’s design. For instance, if not designed to retain water, it is necessary to implement a drainage site in the structure so the water pressure behind the wall does not cause damage. This may determine the materials used for the construction.
Engineers must determine the force that will be exerted on the wall based on a physics principle. The soil or land is analyzed in terms of whether the land is at rest, active, or passive to determine what types of reinforcements the structure may need in building. The pressure that is exerted on walls by soil is called the Lateral Earth Pressure. Using a formula looking at the gravitational pull in proportion to the horizontal force of the soil, engineers can calculate the angle, design and necessary aspects to include in the project.
Types of Materials Used
One common structure is a basement wall made of cement. The design of the basement is critical to the stability of the house as it is the foundation. Metal rebar is implemented into the design of the basement foundation which offers support to the walls. Depending on the amount and type of soil surrounding the basement walls, there may be specific angles employed in the design as well as increased thicknesses utilized. Some residences still utilize cement retaining walls in addition to their basements however, more commonly, other materials are used to construct the walls needed.
Another material used is stone or rock. These walls are more aesthetically pleasing and have been used in modern designs of homes. Using drystone building techniques also allows for water drainage without having to implement specific methods into the job. These walls are typically used for homes or buildings with terraces, slopes and slants in their yards. Common landscaping techniques also use stonework to create beautiful designs. Rocks can also be used by piling them into steel wire baskets to form a wall.
The three main types of retaining walls are gravity walls, piling walls, anchored walls or cantilever walls. Depending on the condition of the soil and the purpose of the wall and space to work within, engineers will decide upon a wall to use. Gravity walls usually require the use of a professional excavator to dig a trench for construction. Gravity retaining walls are designed to lean into the retained earth and are sometimes flexible.
Cantilever walls are constructed using steel-reinforced masonry techniques to secure the soil. The use of buttresses or shorter wing-walls alongside the main retaining wall can also be employed to provide extra support to the structure. The benefit of using a cantilever wall includes utilizing fewer materials for construction. The base of the wall must be placed below the frost point of the ground whereas, gravity walls do not have that restriction.
Sheet piling walls are also another type of retaining wall that is constructed. This technique is used in tighter spaces with soft soil to retain. Using steel, wood planks or vinyl sheets, the materials are driven into the ground to create a wall. Depending on the height of the wall, an anchor may be needed.
A final type of wall that is used is an anchor wall. Anchored walls are simply any of the aforementioned walls using an anchor for added support. Cables, pressurized concrete, and other mechanisms may be used to secure the wall completely.
Regardless of the type of retaining wall that is constructed and the materials used, it is best to hire a professional consultant and engineer to plan and design the wall to suit your needs. Ask for a few consultations to determine the cost and essential elements you will need to include. Also try to incorporate your other landscaping ideas into the mix as you will have to work around the wall.