North Stand Extension, Hampden Park

LocationScotland’s National Football Stadium, Glasgow
RequirementBearing Piles
Techniques
Main ContractorISG

Project Overview

Having provided early technical advice to the consulting engineer, TechnikGS tendered and was then awarded the contract for the design and installation of the bearing piles for the north stand extension.

The works were carried out immediately adjacent to the existing north stand and included the installation of approximately sixty piles to depths of between 5 and 12 metres below ground level

The piles were required to carry loads of up to 450kN in compression and 25kN in shear.

Project Challenges

  • Restricted headroom required under protruding stairwell canopies.
  • Requirement to install piles immediately next to the existing stand walls.
  • Potential for obstructions to be present in the Madeground and underlying Glacial Till.
  • Solution required being low noise so as not to disturb adjacent residents.
  • Programme certainty and cost certainty were required on this contract.

Solution Delivered

TGS provided a low noise, low vibration bottom driven pile solution using restricted headroom minipiling rigs. The crimped ended, thin wall casings were driven using an internal drop hammer to match the required design criteria.

The pile installation system used was particularly appropriate as it allows the driving energy to be delivered directly to the toe of the pile without the level of vibration generated by alternative top-­‐drive systems. The noise levels generated by this technique were also significantly less than those generated with other driven techniques.

As this was a fully displacement pile type, there was not the requirement for spoil disposal. The empty pile casings were reinforced using full length reinforcing bars and cages before the high slump C32/40 concrete was placed.

Ten percent of the piles were dynamically tested one week after installation by an independent testing specialist who confirmed that their load carrying capacity was more than sufficient.

A Sonic Drilling rig was placed on standby for the duration of these works in order to overcome any obstructions if they were encountered. Fortunately all piles were driven to the design depths without obstruction.