Infrastructure problem playbook
Installing secure bridge lighting
Cranked roots and the challenge of bridge projects
The problem
Bridge structures often have restricted depth for installing street lighting columns. Traditional methods, such as "cranked root" foundations, involve offsetting the column's base to fit within the shallow space.
However, these non-standard designs can be compromised during excavation or maintenance work. In turn, instability presents a significant risk.
The impact
Risk to life
Non-standard root designs can be easily compromised, posing significant hazards to both workers and the public
Structural integrity
Inadequate foundations may lead to premature failure of bridge lighting columns, especially under environmental stressors like wind or vibration
Regulatory compliance
Ensuring installations meet health and safety regulations is paramount to prevent legal and financial repercussions.
Real-world example
A notable incident in February 2010 resulted in a fatality. A lamp column with a cranked root design collapsed after its horizontal support was inadvertently cut during nearby street works.
The solution
To mitigate these challenges, NAL has developed the shallow foundation retention socket system, also known as the "bridge deck" retention socket.
This system is engineered to provide a secure foundation for street lighting columns in areas with limited installation depth. So, it's prime for bridge lighting projects.
Features include:
Designed specifically for environments with depth restrictions such as bridge decks – eliminating the need for deep excavations
Manufactured from galvanized cast steel or ductile iron, ensuring durability and longevity even in demanding conditions
Incorporates a stainless-steel locking system that firmly holds the lighting column in place, preventing unauthorised removal and enhancing stability
Allows for straightforward removal and replacement of columns without disturbing the surrounding infrastructure, reducing maintenance time and costs
Actionable steps for urban planners / contractors
- Assess installation sites
Evaluate bridge projects to identify areas with depth constraints that may benefit from shallow foundation solutions
- Consult with NAL experts
Engage with NAL's technical team to discuss specific project requirements and obtain guidance on the appropriate retention socket configurations
- Incorporate retention sockets into design
Integrate NAL's shallow foundation retention sockets into project plans to ensure compliance with safety standards and structural integrity
- Train installation teams
Attend our CPD training on the proper setup and maintenance of the retention socket system to ensure optimal performance
Implementing your solution
By integrating NAL's shallow foundation retention socket system, you can:
- Navigate the complexities of bridge lighting installations
- Implement a reliable, compliant method for installing street lighting on bridges
- Prioritise safety and efficiency