The Small Business Innovation Research (SBIR) Phase I project will investigate the feasibility of establishing reliable values for the elastic properties and strength of a novel macro-composite material construction, as well as investigate the application of this material to impact-recovery structures. The proposed research program will have three major components: mechanical properties, design equations, and manufacturing technology. Both classical micromechanics and a finite element analysis-based method will be employed to obtain the elastic moduli, which will be compared with experimentally-measured coupon values. Strength and failure modes will also be obtained from coupon tests, and the applicability of the strain invariant failure theory to the macro-composite will be evaluated. A mechanics-based procedure will then be established for the design of cylindrical tubes constructed from the macro-composite. These tubes must ovalize and gradually collapse when subjected to bending moments, yet return undamaged to the original configuration upon removal of loads. Several low-cost manufacturing processes for the tubes will be evaluated, including pultrusion and extrusion.
The application of the macro-composite material construction to tubular structures has been demonstrated to result in a significant structural-impact recovery capability. A major commercial application for this material and structural technology has been identified. By using the macro-composite material to reduce the large amounts of damage to roadside structures caused by both vehicle impacts and environmental degradation, annual maintenance dollars will be freed up for more urgent public infrastructure repair and rehabilitation needs.