Retaining walls are built to hold off soil that would otherwise drift downwards. However, they may fail and collapse, resulting in severe damage to the property that they are meant to protect. These failures are mainly caused by incorrect design calculations and improper installation at the time of construction. Collapsing of retaining walls may have severe results, including structural damage, injury or death, disruption of services, property damage, and environmental hazards such as soil erosion. It is, therefore, important to put up proper measures to stop retaining walls from collapsing.
So, how do you stop a retaining wall from collapsing?
This involves putting up measures at the time of construction to ensure the surrounding backfill is never saturated. Saturated backfill is heavier compared to dry soil; thus, it highly increases the pressure applied to the retaining wall, hence putting a strain on the wall that could cause it to collapse, especially if it is not designed to handle a high increase in weight.
Constructing proper drainage systems is the leading way to prevent backfill from being saturated. It ensures that water is being correctly led away from the wall itself and the surrounding structure, thus minimizing the possibility of water retaining in the backfill around the wall. Regrading the area around the wall also leads away water from the wall, ensuring the backfill is not saturated. Additional weep holes around the retaining walls ensure proper surface drainage, thus reducing backfill saturation.
If a retaining wall is not properly reinforced, its ability to support external loads such as soil, water, and wind is hugely reduced, thus making it more likely to collapse when under pressure from such loads. The wall can separate at corners as a result, thus undermining its structural integrity and leading to an increased risk of collapsing. This denies the retaining wall the necessary strength required to withstand pressure from the surrounding soil and other external factors.
Increasing the base thickness of a retaining wall is the best way of ensuring proper reinforcement. This strengthens the front of the wall, especially at the bottom, where it meets the foundation, thus increasing its compression strength. Expanding the base thickness can be achieved by placing concrete around the wall and tapering it to an extent that thickening is no longer required.
Many wall design flaws can quickly lead to retaining wall failure. For instance, a weak foundation is one design flaw that quickly results in the instability of a wall. It is usually signified by a series of serious cracks that result in the wall collapsing.
Proper retaining wall design is very crucial in significantly reducing the chances of the wall collapsing. Assessing the variables that may impact a retaining wall’s stability is essential to guarantee it is designed correctly. This can be accomplished by doing a site assessment to look at possible elements such as the types of soil, water table levels, and nearby constructions.
After the construction of a retaining wall, the soil beneath it might start to sink gradually. This happens as a result of the pressure being applied by the wall above. Typically, minimal foundation settlement is expected after the construction of a wall as the soil continues to compress and compact. However, it might continue beyond the expected point, putting the wall at risk of collapsing due to reduced stability.
Improper foundation settlement is mainly a result of poor compaction of soil during construction. This results in the soil moving downwards to fill in the free spaces, thus undermining the stability of the wall. Poor drainage can also cause improper foundation settlement, which occurs when the soil sinks into the ground to occupy the space left behind by water that has stagnated for a considerable amount of time.
Proper compacting of the soil at the time of construction is the leading way to stopping improper foundation settlement. It reduces the free spaces in the soil, thus denying it the capacity to sink gradually into the ground. Proper drainage can also help as it ensures water swiftly drains through the soil, therefore not leaving free spaces that could result in the soil drifting downwards.
These are the major factors that ensure retaining walls are not at risk of collapsing, as they directly influence a majority of the other factors affecting the stability of retaining walls. Improper design and engineering are characterized by saturated backfill, improper reinforcement, improper foundation settlement, and insufficient anchorage and foundation.
Ultimately, understanding the soil and geology of the site of construction and the surrounding area is the overall leading way to stopping a retaining wall from collapsing as it helps make proper design and engineering decisions and plans. This minimizes the possibility of retaining walls collapsing, reduces retaining wall repair, which could be very costly, and helps implement a proper foundation, a proper drainage system, and a proper reinforcement, which significantly improves the stability of retaining walls.