A team of researchers from the Swiss Federal Laboratories for Materials Science and Technology (Empa) are building sustainable roadways using string, gravel and a robotic arm.

The research team determined that string could be used as a substitute for bitumen — an environmentally hazardous viscous mixture derived from crude oil — to bind and reinforce the asphalt.

Source: EmpaSource: EmpaA robotic arm was used to stack five layers of asphalt and string in a pre-programmed pattern. Once complete, the researchers conducted load tests, discovering that the layers of string and asphalt could withstand pressures equal to 0.55 ton.

Additionally, the new asphalt could be recycled at the end of its lifetime.

Next, the researchers intend to conduct dynamic load testing by applying rolling pressure to the asphalt reinforced with string to simulate real road conditions.

To see how the robotic arm stacks the string and asphalt, watch the accompanying video that appears courtesy of Empa.

To contact the author of this article, email mdonlon@globalspec.com