Bangladesh and Reasons Buildings Collapse
by Timothy J. Corbett
Certification Board, ERMA / President, SmartRisk USA
Introduction
On 24 April 2013, an eight-story commercial building, Rana Plaza, collapsed in Savar, a sub-district near Dhaka, the capital of Bangladesh. At least 547 people died and around 2,500 were injured with many still missing. It is considered to be the deadliest garment-factory accident in history. It has been reported that the elected mayor of the municipality has been suspended for alleged negligence in approving the design and layout of the building including the addition of three stories for the Rana Plaza. The risk of a building collapsing increases significantly when the proper review and approval process of the design and construction is not followed.
Bangladesh Garment Factories
Bangladesh has about 4,000 garment factories and exports clothes to leading Western retailers, and industry leaders hold great influence in the South Asian nation. Its garment industry was the third largest in the world in 2011, after China and Italy. The Bangladesh Garment Manufacturers and Exporters Association estimated the industry at $20 billion-a-year and makes up 80% of Bangladesh’s total exports. Dhaka has become one of the worlds most populous and fastest-growing megacities, driving up the price of land and straining the country’s electrical, power and gas systems. The shortage of land and a propensity for flooding in Bangladesh has prompted many factory owners to build up, rather than out. Additional floors often are hastily added without reference to building codes and approvals. Many factory owners who couldn’t afford to build new buildings because of the high cost of land and limited access to utilities converted hundreds of residential and other buildings into makeshift garment factories to keep up with the demand from Western retailers.
Economic Impact
Before the Rana Plaza building collapse, retailers including Wal-Mart Storesand Levi Strauss & Co. were backing away from factories run by multiple tenants in buildings erected several stories high. Safety experts say those buildings pose higher risks than low-rise factories with single tenants in developing countries. Already, the country is losing garment orders after several industrial accidents and political turmoil, in a trend that could hobble its economy and open the doors for other Asian exporters to boost their sales to the U.S. and Europe. The Walt Disney Co., the world’s largest licenser, told licensees in March that they could no longer manufacture its branded merchandise in Bangladesh. The move was part of a larger effort to shift the production of Disney-branded goods out of what it considers countries where factories run a high-risk of safety problems, including Bangladesh, Pakistan and Venezuela.
Building Failures
Causes of building failures including those in developing countries can be attributed to faulty design, poor construction workmanship, product failure or lack of following building codes and regulatory requirements. Building failures could be the result of flaws at any, or all of the stages of design through construction. In developing countries, building failures can be blamed on one, or several factors including the building owners, and developer’s failure to comply with building regulations, or the architects and engineers, contractor as well as government agencies or officials failure to perform its duty in compliance with established building codes construction requirements.
On 17 July 1981, two suspended walkways through the lobby of the Hyatt Regency Hotel in Kansas City, Missouri, U.S.A. collapsed, killing 114 and injuring 200 people. The collapse was due to a late change in design, altering the method in which the rods supporting the walkways were connected to them, and inadvertently doubling the forces on the connection. The failure highlighted the need for good communication between design engineers and contractors, with checks on designs and on contractor-proposed design changes. The failure is a standard case study on engineering courses around the world, and is used to teach the importance of ethics in engineering.
In a building collapse, a structural failure occurs when the material is stressed to its strength limit, thus causing fracture or excessive deformations. In a well-designed system, a localized failure should not cause immediate or even progressive collapse of the entire structure. The causes of a building collapse can usually be attributed to one, or a combination of the following:
- Design Error
- Poor Construction Workmanship
- Extraordinary Loads
- Time and Cost Restrictions
- Professional Ethics and Regulatory Compliance
Design Error
Design error does not mean only an error in a design plan and/or calculation. It can also relate to a failure to account for the appropriate structural loads of the building, the use of incorrect theories, reliance on inaccurate data and information, not considering the effects of spontaneous stresses, and the improper selection of materials or products.
Buildings are supposed to be designed to support certain loads. The loads include the weights of the people, objects and the pressure of rain, snow and wind on the building. Together these are called live loads. Dead load is the building itself. A building collapse caused by a design error could be the miscalculation and detailing in the plans including structural and architectural drawings and the failure to view the building as a whole single unit; lack of adequate soil samples, investigation, proper recommendations including compaction; lack of the use of laboratory tested building materials and the use of a Quality Control & Quality Assurance process.
Poor Construction Workmanship
Faulty construction and poor workmanship has been one of the major causes of structural and building failures. This can include the use of salty sand to create concrete, and the use of inferior steel or an inadequate amount of rebar specified, poor riveting, improper tightening torque of nuts, bad welds, and the use of other improper construction practices. Collapse may arise from the use of an inexperienced site engineer observing the construction process; lack of proper construction experience and supervision; lack of inspection, and the use of substandard building materials.
Extraordinary Loads
Extraordinary loads are often weather related such as heavy snowfall from a blizzard, the shaking created by an earthquake, or the winds and rain of a hurricane. A building that has been designed and constructed considering the extraordinary loads for the location and region should be capable of meeting the load challenges.
Time and Cost Restrictions
Excessive involvement and restriction placed by building owners have also compromised the quality of a building when they are focused primarily on saving time and reducing building costs. Limited budgets and reducing a project schedule beyond a reasonable timeframe usually compromises the quality of the construction and the selection of the materials used. Critical decisions made regarding construction material could definitely reduce the characteristic strength and the buildings response when exposed to the internal and external stresses. These decisions can eventually lead to collapse, if not immediately, most likely over time.
Professional Ethics and Regulatory Compliance
When the project team involved in the daily construction work does not follow proper professional ethics as it relates to construction practices, discipline and respect for standards, this is cause for professional negligence as well as poor construction workmanship. These practices can easily lead to building failure and collapses during construction or after completion of the project. The failure by political officials, regulatory agents, and local authorities responsible for inspecting building sites has contributed to building collapses by not following, or by circumventing the established building and approval process. At his point, it appears this is one of the main alleged causes for the Rana Plaza collapse.