Reserachers at the University of Wisconsin-Milwaukee have developed a durable, water-resistant, and malleable concrete formulation - called Superhydrophobic Engineered Cementitious Composite (SECC) that they estimate could last more than 120 years. The engineered the composite to resist cracking using two superior characteristics. First, they made the concrete superhydrophobic. "Additives in the hybrid change the concrete on a molecular level when the pavement hardens, creating a spiky surface that, although microscopic, causes the water to bead and roll off," said the University press release. Second, the SECC gains some flexibility by mixing thin unwoven poly(vinyl alcohol) fibres into the concrete, which help prevent crack growth. By allowing small cracks to form, but not grow, the fibres help distribute stress loads through small spaces that water cannot penetrate.
