Scientist Take Inspiration From the Natural World to Build Indestructible Bridge

Researchers from the University of Warwick are devising new mathematical models inspired by simple patterns found in nature to develop an indestructible bridge capable of withstanding loads and stresses with ease.

According to a paper published in the journal Proceedings of the Royal Society A, the new mathematical models are based from a design process called "form-finding." Form-finding is a design process that enables rigid structures to follow strong natural form. Structures with natural form are sustained by a force of pure compression or tension, with no bending stresses.

"Nature's design principles cannot be matched by conventional engineering design," explained Wanda Lewis, an Emeritus Professor at University of Warwick's School of Engineering, in a statement. "Aesthetics is an important aspect of any design, and we have been programmed to view some shapes, such as circular arches or spherical domes as aesthetic. We often build them regardless of the fact that they generate complex stresses, and are, therefore, structurally inefficient,"

Professor Lewis has been observing different forms and shapes found in nature, including outlines of a tree or a leaf, the curve of a shell, the way a film of soap can suspend itself between chosen boundaries, for 25 years. Professor Lewis noted that these structures in nature tend to develop simple stress patterns capable of withstanding forces applied to them.

In a form-finding experiment, Professor Lewis suspended a piece of fabric to relax into its natural, gravitational, minimum energy state. She froze the shape of the relaxed fabric and inverted it. She then simulated the gravitational force applied to the structure to compute the coordinates of the shape. After the experiment, the piece of frozen fabric became a shape that can withstand loads with ease.

At present, engineers have been using the catenary forma and inverted parabola to build the optimal arch for bridges. However, both shapes can only withstand specific type of load without developing complex stresses. The new form-finding process can be developed without such weaknesses, resulting to a structure that have enhanced safety and long durability, without the need of repair and restructuring.