Each day seashell waste continues to accumulate. This generates thousands of tons of potential resources essentially disposed without further use – aside from the few shells repurposed for crafts and environmental restoration. Not that some countries haven’t tried to use seashells to combat the growing economic and environmental hazard. For example, various types of shells have been used as a material for driveway pavement projects successfully.
More than a few researchers have tried to find ways to incorporate seashells into the construction industry even more. Seashells are attractive because of their high calcium carbonate content, which yields improved strength properties compared to other resources.
Unfortunately, even if seashells turn out to be a great material, adjusting batches and recipes to accommodate new resources is costly and time-consuming. Additionally, acquiring seashells for many manufacturers would not be as easy as current avenues for obtaining materials.
Pervious pavement uses
Recent research used crushed slipper limpets, scallops and queen scallops as aggregates to test the durability of pervious concrete. The researchers concluded the concrete with crushed shells was significantly weaker on almost every front. Between the higher chance to clog and the increased fragileness of the concrete during freezing and thawing, there doesn’t seem to be much use for these seashells as a pervious pavement material. The researchers did remain optimistic, however, and asserted that using shells in pervious concrete should be feasible after more research and tests.1
Sand or cement powder replacements
A group of undergraduates recently completed their final project – with the oversight of several professors – by looking at oysters and conch shells as feasible sand and cement powder replacements. They performed a variety of tests, which involved manually crushing shells for their mixtures. Unfortunately, the students found these mixtures lacked the necessary strength to be a full replacement for our favorite material staples. In fact, they discovered the best mix replaced only 5 percent of cement powder with conch shells.2
We are never ones to shy away from innovation, and even though the research doesn’t seem to be on the side of seashells right now, that does not mean a breakthrough won’t occur with further research in the future. Follow our blog, and we’ll keep you posted on new developments as they unfold.
- D. Nguyen, M. Boutouil, N. Sebaibi, F. Baraud, L. Leleyter, Durability of pervious concrete using crushed seashells, Construction and Building Materials 135 (2017) 137-150
- A. Ramirez, S. Barker, T. Love, E. Milazzo, L. McGillicuddy, A. Sakulich, N. Rahbar, W. Towner, Waste shell cement composites, 1-69