Delivering 120-Year Stability with Passive Anchors at Canal Rd, Bradford

Supporting long-term wall stability for Sheet Piling UK in a constrained riverside location

Project Background

Ischebeck TITAN partnered with Sheet Piling UK to support the design and installation of a permanent sheet piled retaining wall along the perimeter of an undeveloped site between a busy highway and river. The scheme formed part of a long-term infrastructure solution and required a 120-year design life, with the wall providing permanent support and passive restraint to the surrounding ground.

The works comprised approximately 120+ linear metres of sheet piled wall, with passive ground anchors installed at regular centres to ensure long-term stability and performance. Hilliards, were appointed as the installation contractor, with the anchoring system forming a critical element of the permanent works design.

Challenges

Although the installation of the sheet piles was relatively straightforward, site conditions presented several technical and environmental challenges. Ground conditions varied significantly along the length of the wall, comprising made ground and alluvium overlying Pennine Lower Coal Measures mudstone. Depth to competent bedrock was inconsistent, meaning overall anchor lengths varied across the site. The passive tie system was designed to achieve reliable geotechnical performance through the provision of minimum rock socket lengths of between 5.0m and 6.0m, tailored to the local ground conditions and loading requirements.

The proximity of the works to the river introduced additional environmental constraints. Drilling operations had to prevent contamination of the watercourse and comply fully with environmental regulations. This required careful control of flushing methods, capture and management of drilling spoil, and avoidance of silt-laden discharge during installation.

Download Case Study

Access constraints also played a significant role in defining the installation methodology. With limited working space and no external access available, all drilling operations had to be undertaken from within the site boundary using an over-reach approach.

These constraints ruled out many traditional anchoring systems and demanded a compact, adaptable solution capable of operating safely and efficiently in confined conditions.

Solution

To overcome these challenges, the project team selected a self-drilling passive anchor solution using the Ischebeck Titan 40/20 hollow bar system. A total of 49x passive anchors were installed at 1.40m centres, one per sheet pile pan, at a nominal inclination of 45 degrees below horizontal, with adjacent anchors adjusted by ±2 degrees to avoid interaction.

Each anchor utilised a minimum 90mm sacrificial drill bit, enabling drilling and grouting to be completed in a single operation. This approach proved well suited to the variable ground conditions and restricted access, while maintaining installation efficiency and quality. In total, over 1,000 metres of hollow bar were supplied and installed as part of the permanent works.

Corrosion protection was provided through a hybrid system, with black hollow bar fully encapsulated in grout below ground and galvanised bar sections and anchor heads used where the steel was not grouted. The design and verification of the anchors followed BS 8081, with Ischebeck’s patented thread geometry controlling crack widths to below 0.1mm, ensuring durability for the full design life.

Despite challenging ground conditions and environmental constraints, the installation was completed safely and within a four-week programme, delivering a robust, permanent passive anchoring solution that provides long-term stability and confidence in performance.