INFRASTRUCTURE |
Beyond Europe’s barriers of waste
Recycling roadside guardrails promises to reduce CO2 emissions by 70% and cost 10% less. Refurbished barriers must meet the same stringent safety conditions as newly made guardrails. A trial project in the Netherlands has demonstrated this can be achieved Words | Nicola Massara, head of international strategy, Meiser Straßenausstattung, Germany
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n November 2021, world leaders met in Scotland in the latest attempt to reach agreement on tackling climate change. Since the 2015 Paris Agreement, countries have been committed to adapt to its impacts and mobilize the funds necessary to do so. Environmental conservation and carbon footprintreduction are no longer marginal issues, but global priorities. For years, the principle of reduce, reuse, recycle has helped reduce the waste we throw away. Waste can be managed in several ways, each with its own climate change impacts. Let’s consider our business at Meiser – the production of steel guardrails for road safety – and the environmental implications of protecting motorists.
Wasted lifespans
Poor road safety is a symptom of transport dysfunction. Road crashes kill and seriously injure many
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Intertraffic World | Annual Showcase 2022
thousands each day and their economic impact is between 2% and 4% of GDP. While the average service-life of steel constructions is 20 years, many guardrails are replaced much earlier. The lifespan of guardrails expire when they are completely rusted or their zinc layer has washed away. When roads are renovated, often the guardrails have not reached this stage. Renovating guardrails therefore makes sense in terms of emissions reduction. There are several benefits to renovating steel structures, which are already shaped and galvanized. It conserves raw materials and reduces energy-expenditure and CO2 and NOx emissions generated in the production of new steel. The economic advantages compared to new production are also substantial. US highways departments have conducted in-house recycling operations for used guardrail
and guardrail posts for 25 years. These use existing guardrails removed under normal contracts for reconstruction, rehabilitation or widening of primarily interstate highways. Guardrails from such projects are delivered to a dedicated yard, where specialized workers straighten bent or damaged rail or posts with a rolling-machine that restores the rail beam to its original W-shape. Straightened rail and posts are galvanised by a contract vendor then returned to the yard and reinstalled on the roads.
Safety first
Before considering specifications for using recycled materials in highway safety applications, it is necessary to understand existing test procedures and design requirements. The foremost design concern for most safety features is impact performance. Generally, roadside
