SBIR Phase II: Low-Cost Glass Fiber Composites Tailored Towards Concrete Reinforcement

SBIR 第二阶段：专为混凝土加固而定制的低成本玻璃纤维复合材料

• 批准号: 0215179
• 负责人: Fadhel Aouadi
• 金额: $ 50万
• 依托单位: DPD INC
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-01 至 2005-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0215179&HistoricalAwards=false
• 关键词: SBIR; Phase; II; Low; Cost

This Small Business Innovation Research (SBIR) Phase II project will refine the polymer matrix of glass fiber composites with ion exchangers in order to enhance their longevity in the alkaline environment of concrete. Glass fiber composites offer a desirable balance of performance and cost for replacement of corrosion-prone steel reinforcement in concrete; their rapid deterioration in the alkaline environment of concrete is, however, a major setback. Ion exchangers are insoluble solids carrying cations (or anions) which can be exchanged with ions of the same sign. Cation exchangers of hydrogen form replace alkali metal cations (e.g., K + in alkaline solutions diffusing into the polymer matrix) with H + . This exchange of cations neutralizes aggressive alkaline solutions by converting K + OH - (and Na + OH - , etc.) into H2O. Through laboratory investigations and industrial-scale pultrusion efforts, the Phase I research demonstrated that introduction of selected ion exchangers into the polymer matrix (or a surface layer of matrix) does not interfere with the pultrusion process, and yields significant gains in alkali resistance of glass fiber composites. The Phase I effort also established a theoretical context for selection of the dosage of cation exchanger in the polymer matrix of glass fiber composites, and verified the economic viability of our approach. The proposed Phase II project will: (1) develop refined theoretical principles and design procedures for formulation of polymer matrices with ion exchangers; (2) develop and experimentally verify optimum polymer matrix formulations incorporating ion exchangers; (3) optimize the pultrusion process of glass fiber composites with the refined polymer system, and fully characterize the end products; and (4) evaluate the structural performance and durability of concrete systems reinforced with refined glass fiber composite bars through comprehensive laboratory studies complemented with a field investigation involving design, construction and monitoring of a reinforced concrete bridge deck. The Phase II effort will receive critical support from major manufacturers of composite rebars (including Hughes Brothers, the world leader in this field), the leading supplier of ion exchangers (Dow Chemical), Michigan Department of Transportation, and Michigan Economic Development Corporation. Michigan State University (Composite Materials & Structures Center) will also take part in the proposed research effort.Close to one-third of reinforced concrete structures, including bridges, parking structures, buildings in coastal areas and offshore structures, are exposed to corrosive environments (deicer salt, seawater spray, etc.); domestic sales of steel for reinforcement of these concrete structures is about $2 billion/yr. Glass fiber composites embodying our technology are resistant to both corrosive effects and the alkaline environment of concrete; they offer a desirable balance of performance and cost to replace steel reinforcement in corrosive environments. Major savings in life-cycle cost can be realized at competitive initial cost through replacement of steel reinforcement with alkali-resistant glass fiber composites in concrete structures exposed to corrosive environments. Glass fiber composite jackets and sheets applied onto concrete surfaces for repair/rehabilitation purposes are also prone to attack by the alkaline pore solution of concrete, representing another market opportunity for our technology. We have filed a patent application, and have reached agreements with Dow Chemical (leading supplier of ion exchangers) and Hughes Brothers (world's leading manufacturer of composite bars for concrete reinforcement) towards transfer of the technology to marketplace.

该小型企业创新研究（SBIR）第二阶段项目将使用离子交换剂改进玻璃纤维复合材料的聚合物基体，以提高其在混凝土碱性环境中的寿命。玻璃纤维复合材料提供了一个理想的性能和成本的平衡，以替代混凝土中易腐蚀的钢筋;然而，它们在混凝土的碱性环境中的快速劣化是一个重大的挫折。离子交换剂是携带阳离子（或阴离子）的不溶性固体，其可以与相同符号的离子交换。氢形式的阳离子交换剂替代碱金属阳离子（例如，碱性溶液中的K +扩散到聚合物基质中）与H +。这种阳离子交换通过将K + OH -（和Na + OH -等）转化成水通过实验室研究和工业规模的制浆努力，第一阶段的研究表明，将选定的离子交换剂引入聚合物基体（或基体的表面层）不会干扰制浆过程，并在玻璃纤维复合材料的耐碱性方面产生显着的收益。第一阶段的努力也建立了一个理论背景下的阳离子交换剂的玻璃纤维复合材料的聚合物基体中的剂量的选择，并验证了我们的方法的经济可行性。拟议的第二阶段项目将：（1）开发用于配制具有离子交换剂的聚合物基质的精细理论原理和设计程序;（2）开发并实验验证含有离子交换剂的最佳聚合物基质配方;（3）优化具有精细聚合物体系的玻璃纤维复合材料的制浆工艺，并充分表征最终产品;及（4）透过全面的实验室研究，并辅以涉及钢筋混凝土桥面板设计、施工及监察的实地调查，评估以精制玻璃纤维复合钢筋加固的混凝土系统的结构性能及耐久性。第二阶段的工作将得到主要复合钢筋制造商（包括该领域的世界领导者Hughes Brothers）、离子交换剂的领先供应商（Dow Chemical）、密歇根州交通部和密歇根州经济发展公司的关键支持。密歇根州立大学（复合材料结构中心）也将参与拟议的研究工作。近三分之一的钢筋混凝土结构，包括桥梁、停车场结构、沿海地区的建筑物和海上结构，都暴露在腐蚀性环境中（除冰盐、海水喷雾等）;用于加固这些混凝土结构的钢材的国内销售额约为20亿美元/年。体现我们技术的玻璃纤维复合材料可抵抗混凝土的腐蚀作用和碱性环境;它们提供了性能和成本的理想平衡，可在腐蚀环境中取代钢筋。在暴露于腐蚀环境的混凝土结构中，通过用耐碱玻璃纤维复合材料取代钢筋，可以以具有竞争力的初始成本实现生命周期成本的重大节省。应用于混凝土表面的玻璃纤维复合材料护套和片材也容易受到混凝土碱性孔隙溶液的侵蚀，这是我们技术的另一个市场机会。我们已经提交了专利申请，并与陶氏化学（离子交换剂的领先供应商）和休斯兄弟（世界领先的混凝土钢筋复合棒制造商）达成协议，将技术转移到市场。