Sea sponges inspire the next generation of skyscrapers and bridges

When we think of sponges, we think of something soft and squashy. But Harvard John a. Researchers at the Paulson School of Engineering and Applied Sciences (SEAS) are using marine aquatic glass skeletons as inspirations for the next generation of strong and lean buildings, long bridges and light spacecraft.

In the new paper published in Nature stuff, The researchers showed that the diaphragm-like skeletal structure of Euplectella aspergillium, a cold-water marine sponge, has a higher strength-weight ratio than the traditional mesh structures used for centuries in the construction of buildings. And bridges.

“We found that the sponge’s diagonal reinforcement strategy achieves the highest buckling resistance for a given amount of material, which means we can create stronger and more resilient structures by intelligently rearranging the material inside the composition,” said Matthias Fernandez, a graduate student. Sea and the first author of the paper.

“In many fields, such as aerospace engineering, the weight-to-weight ratio of the structure is very important,” said James Weaver, senior scientist at CAS and one of the corresponding authors of the paper. “This biologically inspired geometry can provide a way to design lighter, stronger structures for a variety of applications.”

If you’ve ever crossed an awning bridge or kept up with a metal storage shelf, you’ve seen the diagonal lattice architectures. This type of design uses many small, closely spaced diagonal beams to distribute the applied load evenly. This geometry was patented in the early 1800s by architect and civil engineer, Ethel Town, who wanted a method of building sturdy bridges from lightweight and inexpensive materials.

“The town developed a simple, inexpensive, effective way to stabilize the structure of the square lattice, which is still used today,” Fernandez said. “That work gets done, but it’s not the best, which leads to wasted or useless content and a hat of how tall we can be. Can we use less material to achieve the same power in the end? “

Fortunately, the glass sponges, a group that includes Eupactella aspergillum, otherwise known as the Venus ‘Flower Basket’, began about half a billion years ago in the direction of research and development. To support its tubular body, the euplectella aspergillum employs two sets of parallel diagonal skeletons, intersecting each other and joining the underlying square grid to create a strong checkerboard-like pattern.

“We’ve been studying structure-function relationships in sponge skeletal systems for over 20 years, and these species continue to amaze us,” Weaver said.

In simulations and experiments, the researchers copied this structure and compared the skeletal architecture of the sponge with the geometry of the existing lattice. The composition of the sponge withstood the heavy load without buckling, leaving it all behind. The researchers showed that the overall structural strength improved by more than 20 percent, without the need to add additional materials to achieve this effect in the parallel cross diagonal structure.

“Our research has shown that the lessons learned from the study of sponge skeletal systems can be geometrically optimized to construct the structure, with vast suggestions for the use of improved materials in modern infrastructure applications,” said William and Ami Kuan. Danoff of C.A.S. Professor of Applied Mechanics and corresponding author of the study.