Rethinking Materials in a Changing World
Imagine the concrete used to build our cities. Every building, road, and seawall you see is made mostly from concrete—a material that requires huge amounts of energy and natural resources to produce. When we make concrete, we burn limestone in huge kilns, releasing carbon dioxide (CO₂) into the air. CO₂ is one of the main gases driving climate change. This means that our everyday construction methods are not only building our cities but also adding to the global warming problem.
In places like Miami, the situation is even more critical. Miami is a coastal city facing rising sea levels due to climate change. As sea levels rise, more water encroaches on the land, threatening homes, roads, and infrastructure. Additionally, Miami’s shores are hit hard by natural forces like storms and high tides. Traditional concrete doesn’t always stand up well to these challenges, which means repairs and rebuilding become more common—and that, in turn, uses even more resources and energy.
“Our everyday construction methods are not only building our cities but also adding to the global warming problem”
Transforming sargassum from a waste product into a valuable resource presents a promising avenue for sustainable construction. Companies like Sargassum Eco Lumber are pioneering methods to convert sargassum and plastic waste into eco-friendly building materials, addressing both waste accumulation and the demand for sustainable construction resources.
The Need for Innovation in Miami-Dade
Miami-Dade County has recognized the urgency of addressing sargassum influxes and is seeking sustainable solutions.The Miami-Dade Innovation Authority has issued challenges to develop novel methods for repurposing sargassum, emphasizing the county's commitment to innovative, environmentally responsible approaches.
By embracing nature-based solutions and integrating materials like sargassum into architectural and construction practices, coastal communities can enhance resilience, promote sustainability, and turn environmental challenges into opportunities for innovation and growth.
Research Questions
This study aims to bridge these gaps by focusing on Miami’s Sargassum species and evaluating both its physical and mechanical properties in concrete. This study builds upon previous material research by conducting a local investigation, seeking to contribute to sustainable solutions for Miami’s Sargassum waste management strategies. This study aims to answer four key questions:
What chemical transformations occur when locally collected Sargassum is incorporated into concrete?
How does locally selected Sargassum-based concrete perform at 10% cement replacement levels in terms of compressive strength compared to previous studies?
What are some effective real-world applications for integrating Sargassum into marine and coastal infrastructure in Miami-Dade?
Turning a Problem into a Resource:
Every year, massive amounts of sargassum wash up on Miami’s beaches. Normally, this seaweed is seen as a nuisance—it can foul beaches, harm local ecosystems, and even impact tourism. By turning sargassum into a useful construction material, we not only address the waste problem but also reduce the environmental impact of building materials.
The Impact of Coastal Erosion and Waste Management
Coastal erosion threatens infrastructure, habitats, and economies. Traditional mitigation methods, such as concrete seawalls, often exacerbate environmental degradation and disrupt natural coastal dynamics. Miami's proposal for a 20-foot sea wall underscores the urgency but also highlights the need for more sustainable solutions.
Simultaneously, waste management issues, particularly concerning sargassum seaweed, have intensified. Since 2011, unprecedented quantities of sargassum have inundated coastlines, with blooms measuring over 1,600 square kilometers—more than three times the average size. These events have caused millions of dollars in lost tourism revenue, especially impacting small Caribbean countries reliant on seasonal visitors.
Improving Coastal Resilience:
As sea levels rise and storms become more severe, cities like Miami need stronger, more resilient infrastructure. Concrete made with sargassum shows promise in being just as strong as traditional concrete while also offering better thermal properties—helping buildings stay cooler during hot days. This improved durability and thermal efficiency means buildings and coastal defenses (like seawalls) could last longer and perform better in harsh coastal conditions.
A Climate-Responsive Approach
My research shows that by rethinking our materials—using sargassum-infused concrete—we can reduce harmful emissions, turn a local waste problem into a resource, and build more resilient structures that protect cities like Miami. This is not just a technical fix; it’s a step toward a more sustainable, climate-adaptive future for coastal communities.
By adopting bio-based materials, Miami can take a major step toward climate-responsive construction. Not only does this approach help lower greenhouse gas emissions, but it also supports the city’s efforts to protect its coastal areas. Building with materials that work with the environment—rather than against it—can make coastal cities more resilient to the impacts of climate change.
