Structural Repairs and Piling Oxford
Newman Building Solutions were once again called upon by Oxford City Council to carry out a detailed structural survey in order to diagnose the cause of cracking and to design a suitable structural repair programme to repair the defects to these low level flats occupied by elderly tenants.
In order to assess the cause of cracking to the building a visual inspection of the masonry was carried out as well as utilising our in house soil investigation and drainage survey team to assess all causes to the cracking.
Our surveyor carried out an extensive investigative survey and discovered the cause of cracking was due to subsidence caused by vibration from the high speed rail track situated less than 20m’s from the property. The soil investigation discovered that the property was built on firm to stiff clay which is common across the South East of England but the foundations, which we would usually assume as being a concrete slab was actually just a non reinforced ring beam built on made up ground. Our drainage survey concluded that no drains were defective.
In order to repair the cracked masonry a piling scheme would need to be implemented combined with a Twistfix helical solution to repair the cracked masonry. Over 300 metres of helical bar was installed into the bed joints to reinforce and tie the cracked masonry creating load bearing masonry beams within the bed joint to distribute the structural loads in conjunction with BRE standards.
When our engineers devised the piling scheme we had to ensure that minimum disruption to the elderly tenants as their properties were to remain lived in whilst works were being carried out. The solution was to install 300mm augured piles 10 metres into bedrock with 10 pile caps in total and 2 piles within each pile cap one acting on the compressive forces and one on the tensile loads to ensure that all load’s would be restrained.
Brick repairs were carried out to the front of the property for aesthetic reasons in order to preserve the building as the brick work had come out of line due to subsidence causing the building to rotate. The structural repairs and piling works took only 10 days to complete and the contract was delivered on time and well within budget.
Newman Building Solutions work with many councils and insurance companies on similar projects and if we could be of assistance please do not hesitate to contact your nearest office.