Many of the City of Johannesburg’s bridges are in poor condition, according to the Johannesburg Roads Agency’s (JRA’s) 2021/2022 Annual Report. The JRA highlights that 14 bridges have been flagged as ‘high priority’ and only 5.77% as ‘good’ or ‘very good’. More than 94% are classified as ‘fair’, ‘poor’ or ‘very poor’. As a result, the city has embarked on various bridge replacement and rehabilitation projects.
Fast-track, high-pressure bridge demolition projects, where timeous completion and safety performance is critical, is a specialised area of expertise for Jet Demolition. “Here the increased risk and high-pressure conditions lend themselves to our specific set of expertise,” comments Jet Demolition Contracts and Project Manager Kate Bester.
Bridge-demolition projects are typically on a turnkey, rapid-demolition basis. The company’s innovative, state-of-the-art and technically advanced methods and machinery allow it to tackle the most demanding and complex bridge demolition projects.
These range from all aspects of road safety – from temporary road closure design and implementation, to extensive communication and consultation with the general public, and liaison with all relevant authorities – to engineering suitable demolition methods, planning for unforeseen circumstances, and final road clearing.
Emergency demolition is often required where bridge stability or safety is compromised by an unforeseen event, such as traffic accidents that have impacted on a bridge structure, or vandalism causing structural stability concerns. Emergency bridge projects invariably impact on the travelling public as these are, by nature, unplanned and unforeseen.
“One of the biggest challenges on an emergency bridge project is to mobilise our plant and personnel to the works. If a bridge is suddenly compromised, all traffic in the immediate area is gridlocked, until such time that alternative routes are made available. Under these circumstances, we rely heavily on the assistance of traffic authorities to provide emergency escorts to the site, fast-tracking the establishment of plant and personnel,” explains Bester.
Any form of emergency work is always a concern, as the structural stability of the collapsed or endangered structure is unknown. It is thus critical to have seasoned and experienced demolition personnel on-site as soon as practically possible to thoroughly assess, manage and mitigate the relevant risks.
Often the first responders to an emergency project include operations and engineering team members, who assess the initial risk and provide feedback to head office, advising as to the envisaged methods and resource requirements.
Jet Demolition’s strength lies in its people and plant. Its crews are disciplined, experienced and responsible, with a focus on keeping all team members safe during the most challenging projects. “Furthermore, our redundancy and variety of plant and equipment allows us to respond rapidly to emergency projects, with demolition typically being able to commence within a few hours of the initial incident,” concludes Bester.