New report shows dangers of modern slavery in construction
The report, called H...
The global construction industry faces a “strong risk” of modern slavery, according to a new report by LexisNexis BIS.
The report, called Hidden in Plain Site – Modern Slavery in the Construction Industry, analysed articles from more than 6,000 licensed news sources in more than 100 countries in Europe, the Middle East, North and South America, Africa and Asia between January 2015 and May 2016.
It shows that throughout the global construction industry and its material supply chains, forced labour and other exploitation that constitutes modern slavery are common, concealed and subject to inadequate prevention, policing and prosecution.
It concludes that governments, businesses and the media all have a role to play in combating modern slavery.
The report follows a pledge by new UK Prime Minister Theresa May in July to spend £33 million on global initiatives to tackle modern slavery. She described it as “the great human rights issue of our time”.
Mark Dunn, Director at LexisNexis Business Insights Solutions, notes: ‘Our report shows that there is a strong risk of forced labour taking place in the construction industry and its supply chains. Given that the construction industry employs an estimated 7% of the global workforce, this means countless thousands of workers are leading lives of misery and injustice.
‘Forced labour needs to move up the global agenda. A wide range of stakeholders – international bodies, governments and the public sector, industry organisations, construction companies, investors, the media and civil society – have roles to play in preventing and avoiding collusion in worker exploitation in the construction industry. LexisNexis BIS is committed to actively working to advance the rule of law, through its day-to-day business, products and services, and its actions’.
Kevin Hyland OBE, UK Independent Anti-Slavery Commissioner, said: ‘I am pleased to see numerous sectors waking up to the crime of Modern Slavery, and the Lexis Nexis BIS report excellently educates those in the construction industry on this evil crime.
‘Businesses, government and civil society have a crucial role in combatting modern slavery, and this report highlights just that. Through responsible media reporting, businesses especially are encouraged to be open about supply chains, and ultimately protect those most at risk of exploitation.
‘Those in construction are especially vulnerable to this crime; with high demand for low wage labour, we must therefore strive to see a thriving construction industry that values ethical recruitment and fair employment if we ever hope to end this evil trade in human beings.'
The report is based on desk research, expert insights and analysis of wide-ranging media coverage. It defines the scope and many aspects of the problem, and breaks it down according to region (Europe, Middle East, North and South America, Africa, Asia) and the procurement of specific building materials. Relevant international regulation and standards frameworks, along with individual countries’ legislative measures (or lack of them), are examined.
Case studies in the report include allegations of forced labour being used to build World Cup 2022 stadiums in Qatar, a marine construction project in the USA, and Brazilian workers at an industrial plant in Angola.
In particular, the report relates to compliance with the recently introduced UK Modern Slavery Act 2015. The UK Home Office estimated in 2014 that there were 10,000–13,000 potential victims of modern slavery in the UK.
More than 20 million people are in forced labour globally, the International Labour Organization estimated in 2012. The Walk Free Foundation’s 2016 Global Slavery Index estimates that there are 45.8 million people in modern slavery across the world. In a 2015 report by the European Union, construction ranked second on the list of economic sectors in the EU most prone to labour exploitation. Of the 21 countries that participated in the research, nine put construction at the top of their list.
Read the September 2016 issue of Construction Global magazine
Why engineers must always consider human-induced vibration
Human induced vibration, or more accurately vibrations caused by human footfall, often conjures images of Millennium Bridge-style swaying or collapsing buildings.
But in reality, the ‘damage’ caused by human-induced vibrations is less likely to ruin a structure and more likely to cause discomfort in people. Though not as dramatic as a structural failure, any good engineer wants to make sure the people using their structures, be it bridges or buildings or anything in between, can do so safely and comfortably. This is why human-induced vibration must be considered within the design process.
Resonance v Impulse
There are two ways that human-induced vibrations affect structures: resonant, and impulse or transient response. Put simply, resonance occurs when Object A vibrates at the same natural frequency as Object B.
Object B resonates and begins to vibrate too. Think singing to break a wine glass! Although the person singing isn’t touching the glass, the vibrations of their voice are resonating with the glass’s natural frequency, causing this vibration to get stronger and stronger and eventually, break the glass. In the case of a structure, resonance occurs when the pedestrian’s feet land in time with the vibration.
On the other hand, impulse or transient vibration responses can be a problem on structures where its natural frequencies are too high for resonance to occur, such as where the structure is light or stiff. Here the discomfort is caused by the initial “bounce” of the structure caused by the footstep and is a concern on light or stiff structures.
Engineers must, of course, design to reduce the vibration effects caused by either impulse or resonance.
Potential impacts from human induced vibration
Human induced vibration can lead to a number of effects upon the structure and its users. These include:
- Interfering with sensitive equipment Depending on the building’s purpose, what it houses can be affected by the vibrations of people using the building. Universities and laboratories, for example, may have sensitive equipment whose accuracy and performance could be damaged by vibrations. Even in ordinary offices the footfall vibration can wobble computer screens, upsetting the workers.
- Swaying bridges One of the most famous examples of human-induced resonance impacting a structure occurred with the Millennium Bridge. As people walked across the bridge, the footsteps caused the bridge to sway, and everybody had to walk in time with the sway because it was difficult not to. Thankfully, this feedback can only occur with horizontal vibrations so building floors are safe from it, but footbridges need careful checking to prevent it.
- Human discomfort According to research, vibrations in buildings and structures can cause depression and even motion sickness in inhabitants. Tall buildings sway in the wind and footsteps can be felt, even subconsciously by the occupants. It has been argued that modern efficient designs featuring thinner floor slabs and wider spacing in column design mean that these new builds are not as effective at dampening vibrations as older buildings are.
- Jeopardising structural integrity The build-up of constant vibrations on a structure can, eventually, lead to structural integrity being compromised. A worse-case scenario would be the complete collapse of the structure and is the reason some bridges insist that marching troops break step before crossing. Crowds jumping in time to music or in response to a goal in a stadium are also dynamic loads that might damage an under-designed structure.
How to avoid it
As mentioned, modern designs that favour thinner slabs and wider column spacing are particularly susceptible to all forms of vibration, human-induced or otherwise, but short spans can also suffer due to their low mass. Using sophisticated structural engineering software is an effective method for engineers to test for and mitigate footfall and other vibrations at the design stage.