2.1.2: Civil Engineering
- Page ID
- 113079
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Modular design is crucial for civil engineers, enabling efficient construction and deconstruction of buildings, bridges, and other infrastructure. By utilizing modular components, projects can be completed faster, with easier maintenance and future upgrades. Below are two strong examples of modular design in action, though many more can be found in everyday life.
Practical Examples
Prefab Bridges
Modern bridges are often constructed using large, prefabricated components that are assembled on-site after being built in a factory. This modular approach allows construction crews to minimize road closure times and ensures that sections are tested for safety before installation. As a result, roads experience less downtime, and the overall cost of bridge construction is reduced. (1) Up to 60% of a bridge can be constructed offsite. (2)
Prefabricated bridges are also safer. Components created offsite can be made in more controlled environments, which can limit the factors that may cause issues within each component. Additionally, as construction times are reduced, workers must spend less time over hazards such as water and power lines, resulting in safer bridge construction and operation (2).
Prefabricated bridges are also more environmentally friendly. (1) Since they are constructed in controlled facilities, pollutants can be managed more effectively, and emissions can be reduced and regulated, making this method significantly better for the environment. Additionally, the factory can recycle materials, lowering overall material usage. (3)
However, prefabricated bridges do come with risks. If not assembled correctly on-site, they can develop structural issues that require further repairs. These problems could negate the advantages of reduced road closure time and lower emissions, highlighting the importance of precision during the installation process. The costliest part of a bridge closure is often the economic impact of road closures and detours (1). As a result, it is important to weight the impacts of prefabricated bridge components when assembling and designing structures.
Figure 2.3.1. Bridges contain multiple components that are transported and assembled when placed in the desired location
Modular Buildings
Modular design has become increasingly important in residential construction, with modular and prefabricated homes offering a more affordable and efficient alternative to traditional building methods (4). These homes are particularly popular in rural areas, where the logistics of construction can be challenging and costly. Modular homes are not only practical for individual homeowners but also play a significant role in expanding public infrastructure, such as hospitals and schools, where cost and flexibility are key factors.
In education, modular buildings are often used to address the need for rapid expansion. Constructing permanent school facilities is a costly endeavor that follows strict design standards, making future expansion difficult when student populations grow. Modular classrooms offer a flexible and budget-friendly solution, allowing schools to quickly adapt to changing needs without the need for extensive renovations (5). This ability to scale up efficiently has made modular design an increasingly attractive option for school districts facing tight budgets and growing enrollments.
In rural areas, modular homes are particularly beneficial due to their ability to reduce the challenges associated with transporting materials and labor over long distances. Prefabricated buildings help to minimize construction costs, as traditional builders often charge higher rates for projects located far from their central facilities as they have to cover worker travel costs (6). By streamlining the construction and delivery process, modular homes offer a more cost-effective solution for residents in remote areas, who may otherwise face prohibitively high costs for permanent structures.
However, modular buildings are not without drawbacks. Their prefabricated design can make them more vulnerable to natural disasters, such as tornadoes and floods, particularly if they are not placed in well-considered locations. 54% of tornado fatalities occur in mobile homes, dispite making up only 6% of total homes (7). As a result, when opting for modular construction, it is crucial to carefully evaluate environmental factors and ensure that buildings are appropriately positioned to mitigate these risks. Proper site selection and planning can help reduce vulnerability while preserving the benefits of modular design.
Figure 2.3.2. Example of a modular property installed. This strategy allows flexibility and adaptation.
References
(1) Elkaissi, J. Prefabricated Bridge Elements and Systems - ABC - Accelerated - Technologies and Innovations - Construction - Federal Highway Administration. www.fhwa.dot.gov. https://www.fhwa.dot.gov/bridge/prefab/.
(2) Grosskopf, K. The Opportunities and Challenges of Modular Construction | National Institute of Building Sciences. Nibs.org. https://www.nibs.org/blog/opportunit...r-construction.
(3) Garcia, R. EDC-2: Prefabricated Bridges Elements and Systems | Federal Highway Administration. www.fhwa.dot.gov. https://www.fhwa.dot.gov/innovation/...edc-2/pbes.cfm.
(4) Doyle, A.; Holbrook, A. What Is a Modular Home? Pros, Cons and Differences. NerdWallet. https://www.nerdwallet.com/article/m...a-modular-home.
(5) Envoplan. The Advantages And Disadvantages Of Modular Classroom Builds. Envoplan. https://envoplan.co.uk/education-new...ssroom-builds/.
(6) U.S. Department of Labor. Wages and the fair labor standards act. U.S. Department of Labor. https://www.dol.gov/agencies/whd/flsa.
(7) National Weather Service. manufactured/ mobile home safety. https://www.weather.gov/media/wrn/Mo...ager-Final.pdf (accessed 2024-10-23).