HIRE HOISTS FOR BRIDGE DECONSTRUCTION

Innovative Deconstruction in Challenging Environments: Hams Hall Bridge Case Study

Customer Specification

Hams Hall Bridge, a disused rail bridge spanning the River Tame in Warwickshire, stood for over 70 years. The client, AR Demolition, faced a unique challenge due to the bridge's location on the edge of a distribution park with restricted access. The site's single-track road, overhead HV cables, a public footpath, and diverse wildlife added complexity to the project. The operational height was limited to 4.6m, posing a significant obstacle. The client needed a strategic plan for the removal and deconstruction of the bridge while adhering to environmental constraints.

Solution

In response to the intricate challenges, AR Demolition devised an innovative solution that involved the deployment of Red Rooster Lifting air hoists. A bespoke temporary gantry crane system was designed to operate directly over the bridge within the 4.6m headroom restriction. The concept aimed to lift large sections of the bridge, exceeding 20 tonnes, and move them to a designated area outside the HV exclusion zone. Here, more traditional demolition methods could be employed.

The deconstruction was divided into two phases:

Phase 1: Inner Girders and Deck

• Removal of vegetation, ballast, and infill concrete.
• Deconstruction of inner girders and the deck using conventional methods.

Phase 2: Outer Girders and Deck

• Utilization of Red Rooster Lifting air hoists within the gantry crane frame for removing the outer girders and deck bridge section.
• Deployment of 4 x 10 tonne and 4 x 6 tonne air hoists at various stages of the deconstruction.

After the bridge deck removal, a suspended scaffold was progressively stripped, leading to the final phase of retracting the gantry crane rails from over the river. This intricate process involved a reverse guided launch technique.

Equipment Purpose

Red Rooster Lifting air hoists played a crucial role in the success of the project. The specialized equipment, including 4 x 10 tonne and 4 x 6 tonne air hoists, operated seamlessly within the low headroom gantry crane system. Their purpose was to lift and move substantial sections of the bridge during Phase 2, enabling the relocation of the deconstructed components to a designated area for further demolition.

The innovative approach of combining bespoke gantry crane design with advanced air hoists showcased the adaptability of the equipment in challenging environments. The project not only demonstrated the technical prowess of Red Rooster Lifting air hoists but also highlighted the importance of strategic planning in overcoming complex constraints during bridge deconstruction.