I-Corps: ULTRA HIGH PERFORMANCE CONCRETE USING A SUSTAINABLE MATERIAL

I-Corps项目更广泛的影响/商业潜力是开发一种先进的混凝土材料：超高性能混凝土（UHPC），这种材料经久耐用，能够抵抗化学和环境的破坏。随着这种材料的使用，我国交通基础设施的平均寿命可能会大大延长。UHPC具有潜在的价值，因为它具有优异的机械强度、延展性、开裂后性能和更长的耐久性。UHPC可用于预制桥梁构件，桩帽闭合孔，桥面覆盖和修复，以及作为桥梁剪切键的浆液。此外，UHPC配方可以在工作现场由当地承包商使用符合州交通部门和联邦公路管理规范的当地材料生产。I-Corps项目的基础是利用当地材料和粉煤灰、钢渣、石灰石粉等工业副产品开发高性能混凝土（UHPC）。这种材料已被证明具有优异的机械强度和较长的耐用性。由于成本高，UHPC在美国的使用可能受到限制。通过使用当地材料减少水泥、硅灰、钢纤维和细砂含量，可以降低UHPC的成本，提高其耐久性和可持续性。水泥和硅灰的含量可以通过使用粉煤灰和磨碎的粒状高炉渣（GGBS）作为补充胶凝材料（SCMs）来降低。这些scm的使用降低了成本，并产生了生态高效的UHPC。到目前为止获得的实验室结果表明，所提出的材料在抗压和抗拉强度以及耐久性方面与目前可用的产品相当：抗快速冻融循环，抗氯离子渗透，抗硫酸盐侵蚀。快速氯离子渗透性测试结果表明，该材料的氯离子侵入可以忽略不计，而材料具有优异的抗快速冻融循环和硫酸盐侵蚀性能。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The broader impact/commercial potential of this I-Corps project is the development of an advanced concrete material: ultra-high-performance concrete (UHPC) that is durable and able to resist chemical and environmental distress. With the use of this material, the average life span of our nation’s transportation infrastructure may be significantly extended. UHPC has potential value because it is designed with superior mechanical strength, ductility, post-cracking behavior, and longer-term durability. UHPC may be used in applications for prefabricated bridge elements, pile cap closure pores, bridge deck overlays and repairs, and as a grout for bridge shear keys. In addition, the UHPC formulation may be produced on the job site by local contractors using local materials that will meet both state departments of transportation and federal highway administration specifications. This I-Corps project is based on the development of ultra-high-performance concrete (UHPC) using local materials and industrial by-products such as coal ash, steel slag, and limestone powder. This material has been shown to exhibit superior mechanical strength and longer-term durability. UHPC’s use in the United States may be limited due to its high cost. The cost of UHPC may be reduced, and its durability and sustainability improved, by using local materials reducing cement, silica fume, steel fiber, and fine sand contents. Cement and silica fume contents may be reduced by using fly ash and ground granulated blast furnace slag (GGBS) as supplementary cementitious materials (SCMs). The use of these SCMs reduces the cost and results in eco-efficient UHPC. The laboratory results obtained so far indicate that the proposed material is comparable with currently available products in terms of compressive and tensile strengths and durability properties: resistance to rapid freeze-thaw cycles, resistance to chloride ion penetration, and resistance to sulfate attack. The rapid chloride ion permeability testing results showed that the proposed UHPC has negligible chloride ion ingress, while the material exhibited excellent resistance to rapid freeze-thaw cycles and sulfate attack.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.