Retaining walls are built to retain soil to unnatural slopes separating two elevations. Often they fall into a state of neglect and structural defects occur putting the retaining structure into jeopardy of collapse.
There are various techniques used to build a retaining wall and the three common techniques used are called Gravity, Cantilevered and Sheet Piled. There are various other techniques used such as gabion basket, and buttressed walls.
With changes in the earth pressure on the retaining wall, changes in the water table and areas of structural defect retaining walls tend to fail. The damage caused by a failed retaining wall is severe and can lead to injuries to persons within the vicinity causing them to be crushed. It can also be damaging to property as often the retaining wall is retaining soil that the property is built on forming an integral part of the structures foundation strength. A slip in the soil can cause your property to subside. And you may be liable for legal action if you have failed to maintain your retaining wall.
How to identify a Structural Defects to a Retaining Wall?
Cracking and bowing are the main defects that will be evident when a retaining wall fails. This can lead to the wall to collapse completely due to the loss of structural integrity. Retaining walls rely on their ability to act as one structure and with a fracture this will prevent the structure from retaining the soil.
Cracking On Wall
Before cracking and bowing of the wall are evident you should check the condition regularly of the wall after the winter months or periods of heavy rainfall. It is important to check that the pointing is still strong and not defective as this will allow the penetration of moisture. It is also important to check the condition of the face of the brick any spalled bricks should be replaced as again this will allow the penetration of moisture which can cause a structural defect.
How Can My Retaining Wall Be Repaired?
In the early stages of a failed retaining wall it is possible to use helical bar combined with high strength grout as incorporated in the Twistfix System, which Newman’s are approved installers and designers of. With this method it is possible to install lengths of helical bar to create masonry beams which will allow the structure to act as one panel again.
In cases of severe outward movement we employ various techniques of restraining the wall by introducing platypus ground anchors that tie the structure to the ground using high tension cables and pattress plates preventing further outward movement. In instances where the loads are extreme piles have been driven in to the ground to resist the outward movement.
If your retaining wall is suffering structural defects ensure you contact Newman’s for a free survey and repair specification.
Today’s Structural Survey’s included this large Victorian Property located in Putney, South West London.
Defects found during our survey included lintel failure to a number of brick arch Lintels and outward movement to two of the three bay windows on the rear elevation due to a lack of lateral restraint.
Our structural reports include detailed specifications of the recommend repairs include CAD drawings.
If you require a structural survey to your property call us on 0333 444 0154
Tower block construction began in the 1950’s with the first tower block in Britain being built, The Lawn in Harlow, Essex. The need for housing influenced the decision for tower block construction and it boomed.
The Lawn, Essex
Tower blocks are constructed usually using three methods; in-situ, Steel frame with infill panel and pre-fabricated panels. In theory all three methods of construction should have provided structures free from structural defect and with stand the test of time. In reality many high rise structures are in urgent need of refurbishment to ensure they do not enter a state of disrepair with the only solution being demolition.
With all three methods of construction there are common structural defects found that are often similar across the country. Cracking is usually evident within the external and internal fabric of the structure and the defects are often linked to one or more of these causes of movement, thermal movement, lack of movement joints and failed wall ties or inadequate wall ties. Poor construction methods during the build phase. Concrete failure as well is a common structural defect found which can be caused by many factors such as oxidisation of the reinforcing steel, the reinforcing steel being too close to the surface of the concrete which again causes oxidisation freeze thaw action and chemical reaction to name but a few.
Trellick Tower, West London
Newman’s are approved designers and installers of the Twistfix and Thor Helical repair systems combined with our experience we provide our own specifications for wall tie replacement schemes as well as crack stitching and masonry beams. We are also approved installers for Fosroc and Sika concrete repair mortars and resins, mastic and coatings.
When assessing the requirements for repair to tower blocks you should only use an experienced contractor and Newman’s surveyors and engineers have extensive experience carrying out structural surveys and designing structural repair programmes to reinstate the structural integrity to tower blocks. We have worked closely with many principal contractors and façade installation specialists to provide insurance backed repair schemes prolonging the life of the tower block.
We can also provide rope access surveys and installation on schemes that it isn’t feasible to supply and erect traditional access methods such as tube and clip scaffolding or cradle access.
