Demolition work is the most dangerous work in construction, and construction itself is one of the industries with the highest injury rate. Abandoned Didcot Family The tragic collapse and death of the Didcot Family Abandoned Building is a strong reminder of the danger of demolition.
Not long ago, after a major boiler room collapsed, one person died and three were missing. Although it’s still too early to know the real cause of the accident, there are many reasons why buildings are – or before they are demolished.
First, and most importantly, contractors may not fully understand the structural principles of the building they are dealing with. For example, if a critical component is removed-it may be an obvious beam or a component as small as a nut on a specific threaded steel rod-the rest of the building may become unstable and must be inspected by a qualified structural engineer.
A building on Stanley Road in Liverpool collapsed in 2000, killing one person. Sadly, people failed to understand the consequences of changing or removing key parts of the structure. A steel beam was bent back to allow access to the hopper truck, and the steel cable tie has been removed. The staff of the site did not realize that the changes that occurred over time meant that these walls were becoming more and more important in structure.
Sustainable development and circular economy
Recently, the environmental sustainability trend and the emergence of “circular economy” have further exacerbated the problem of structural stability, in which the components and contents of buildings are recycled for resale, reuse or recycling. For example, when a power plant is decommissioned, the machinery and equipment can be expected to be restored. Precious metals can be sold, bricks and wood can be reused, and concrete can even be crushed and recycled.
Since workers are required to “deconstruct” various elements in the building, rather than using long-distance demolition equipment within a safe distance, this can cause major hazards. Basically it is unusual to cut a hole or doorway in the wall so that large machines can be moved in and out easily. Another consequence of this method is that it allows wind to flow through the building, thereby causing the walls to “carry” loads beyond their capacity.
If you do not consider the cumulative effects of removing the fixed machinery that is likely to be fixed to the structural components of the building, removing the part of the wall and other parts of the building, the consequences will be catastrophic.
explosion
Explosion is another major risk. In the case of Didcot, one avenue of investigation may be an accidental explosion. After all, in July 2014, three abandoned cooling towers in Didcot were destroyed by explosives. However, the cooling tower is a relatively simple structure that can be used for explosive demolition rather than excavator or piece by piece. The collapsed building is likely to be demolished through one of these more conventional methods. However, this kind of professional explosion work is always carried out under the control of experienced explosives engineers. Therefore, the more obvious source of explosion may come from the gas or natural gas that fuels the building.
Gas may accumulate in the plant itself, leak from pipelines over time, or may be present in “active” pipelines that are considered “dead” or isolated. In these cases, sparks or fire sources can easily cause an explosion. This kind of explosion tends to kill indirectly, because this force causes the walls to explode and the roof to fall, crushing the workers below. This was the case when a gas pipeline that had been corroding for 35 years caused an explosion at the Stockline Plastics plant in Glasgow in 2004, killing nine people.
Coal dust can also cause such explosions. In fact, if the air is spread and agitated sufficiently, most types of dust can cause an explosion. If the dust/air ratio is right, it is easy to ignite a large number of dust clouds and cause an explosion as destructive as gas.
Early reports indicated that there was an explosion before Didcot collapsed, but it was later denied. However, any reason identified here can only be regarded as a potential means of investigation. The investigation by the British Health and Safety Commissioner will undoubtedly reveal the real cause of the accident in due course.
Hope to learn lessons in the future. But, of course, this has little effect on the families of the dead and missing workers.
How can R&D help?
In our research, we are seeking to develop a national economic approach to address barriers that prevent effective management of Australian construction and demolition waste, such as fulfilling extended responsibilities to producers.
A project aimed at finding ways to integrate supply chain systems into the construction and demolition waste and resource recycling industries is supporting our work.
The goal is to ensure a good connection between all parts in the construction supply chain. A more seamless system will expand the market for these materials and make waste recycling more economically feasible. This in turn will benefit society, the economy and the environment.
