I-Corps: Sustainable Infrastructure Rehabilitation

美国民用基础设施的惊人状况已被充分记录。也有资料显示，目前在现场进行的维修中约有50%失败，需要昂贵的重新维修。除了经济效益之外，重复维修还会给环境和交通运输带来高昂的成本。修复失败可以追溯到修复砂浆的脆性及其从基材上分层的倾向。在这个项目中，该团队提出了一种韧性纤维增强水泥基复合材料，它可以抑制脆性断裂和分层，并且在受损时可以自我修复。这种材料一旦应用，可以永久保护原有的基础设施，延长其使用寿命。通过将工程胶凝复合材料（ECC）引入民用基础设施行业，该团队预计将在许多方面产生广泛的影响。这些措施包括降低基础设施维护的生命周期成本，增强交通基础设施的用户移动性，以及减少民用基础设施建设和反复维修造成的环境成本和影响。该团队开发了具有不同功能的ECC，包括轻量化、低刚度和自修复ECC。轻质ECC的密度约为普通混凝土的40%。这直接转化为减少相同百分比的路面板重量，从预制件场到施工现场的运输成本，以及安装过程中吊装机的能力要求。近年来，用再生轮胎橡胶代替刚性骨料的低e刚度ECC被开发出来。这种材料刚度降低转化为板材刚度降低相同的百分比。自我修复转化为下一代路面板独特的零维护功能。

The alarming condition of civil infrastructures in the US has been well documented. It has also been documented that about 50% of current repairs in the field fail, requiring costly re-repairs. Beyond economics, repeated repairs pose a high cost to the environment and to transportation mobility. Repair failure can be traced to the brittleness of repair mortars and their tendency to delaminate from the substrate. In this project, the team proposes a ductile fiber reinforced cement based composite that suppresses brittle fracture and delamination, and that can undergo self-healing, when damaged. This material, once applied, can permanently protects the original infrastructure and extend its service life. By introducing an engineered cementitious composite (ECC) material into the civil infrastructure industry, the tam expects broad impacts on a number of fronts. These include lowering lifecycle costs of infrastructure maintenance, enhancing user mobility on transportation infrastructure, and reducing environmental costs and impacts caused by the construction and repeated repairs of civil infrastructure. The proposed team has developed ECCs with different functionalities, including lightweight, low stiffness, and self-healing ECC. Lightweight ECC has a density about 40% that of normal concrete. This translates directly to a reduced pavement slab weight by the same percentage, transport cost from precast yard to construction site, and hoisting machine capacity requirement during installation. Recently, a low E-stiffness ECC was developed using recycled tire-rubber in place of rigid aggregates in ECC. This material stiffness reduction translates into a slab stiffness reduction by the same percentage. Self-healing translates into a unique zero-maintenance feature for next-generation pavement slabs.