A devastating magnitude 7.0 earthquake that rocked Haiti in January 2010 instantly created an estimated 20 million cubic yards of waste. More than a year after the disaster, Haitian families and businesses are still trying to rebuild, and the rubble that was once thought to be an impediment to reconstruction is now being viewed as an economical part of the solution.
Photo courtesy of FullerCenter.org
Researchers at the Georgia Institute of Technology say new concrete can be made from recycled rubble and other indigenous raw materials that meets or exceeds the minimum strength standard used in the U.S., an article in the Bulletin of the American Ceramic Society reported. Recycling the debris eliminates two hurdles to reconstruction: limited landfill space for storing the debris and fiscal challenges of importing new building materials. “Based upon these results, we now believe that Haitian concrete debris, even of inferior quality, can be effectively used as recycled coarse aggregate in new construction,” said Kimberly Kurtis, Georgia Tech professor of civil and environmental engineering. “It can work effectively, even if mixed by hand. One key is having a consistent mix of materials that can be easily measured.” But recycling old concrete into new concrete isn’t the only way rubble is being reused in sturdy homes for earthquake survivors. The Haiti Housing Network has found that by using rubble from a family’s previous home, permanent housing for earthquake victims can be built for about $3,000. Beginning with a trench foundation, relief workers use steel mesh to erect a basket-style wall form that is filled with earthquake rubble broken up with sledgehammers. Field-made metal hooks keep the mesh evenly spaced. When the wall baskets are filled, mortar is added to stabilize the structure. Additional coats of mortar provide a finished look, not unlike a concrete block exterior. Rebuilding new homes from the rubble of a previous house is not only a great way to help families remain in their old neighborhood, but it may also provide greater security in the event of another earthquake. Because of the strength of the steel basket and the fact that the contents are allowed to shift during an earthquake, engineers believe the houses will withstand an 8.0 earthquake with only minor cosmetic damage, reports The Fuller Center for Housing.