Newman’s were called upon by a commercial property management company who own various trading estates across London.
Many trading estates in London are still Victorian brick built structures that have stood the test of time and are still fully functional. The masonry construction of most of these structures is built using 13 inch solid masonry laid in English bond using lime mortar. This type of construction is a strong bond which will allow slight movement.
We were called out to attend site as a matter of urgency due to the crack rapidly widening and in some places was over 10mm’s wide. We carried out a structural survey free of charge the same day and designed a repair specification that would restore the structural integrity without any major disruption to the business operating in the building.
We used our own mobile scaffold tower alleviating the need for traditional scaffolding enabling us to be on site just two days after the initial survey.
To repair the crack in the brickwork we installed 14 No masonry beams across the crack which was drilled back into the left and right pillars. This method of crack repair not only crack stitches but distributes the loads imposed and distributes them across the masonry preventing further cracking.
The parapet wall was secured using 1.5m grout ties which were installed vertically down through the brick work which saved huge costs in a rebuild.
The repair was guaranteed against failure for 10 years. The repairs lasted only 2 days allowing the business to remain fully operational.
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.
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.
Another of today’s Structural Survey to investigate a bowing wall on this 1902 block of flats in Knowle, Bristol.
The bulge in the flank wall measures approximately 3.5 metres by 4.5 metres and is due to separation between the inner and outer leafs of masonry, after carrying out our comprehensive survey a solution was achieved using a combination of Twistfix helical bars, Twistfix delamination ties and lateral restraint ties together with deep bed grout injection and ‘re pointing eliminating the need to rebuild the flank elevation at a considerable cost.
Newman’s work closely with structural engineers, building surveyors and loss adjusters offering cost effective modern day methods of building and structural repairs, to see how we can help call 0333 444 0154