CAREER: Bio-Inspired Genetically Engineered Self-Healing for Cementitious Materials

该学院早期职业发展计划(Career)项目的研究目标是对自愈胶凝材料的基因工程方法有一个基本的了解。混凝土和其他胶凝材料本质上是脆性的，在机械和环境压力下容易开裂。因此，在基础设施中，具有裂缝形成后自我修复能力的创新材料是非常必要的。从该奖项的结果中获得的基本见解将推动高性能和智能胶凝材料的发展，通过提高基础设施的耐久性和降低维护成本，为公共安全做出贡献，并造福国民经济。该项目的教育目标是促进STEM学科的参与，特别是代表不足的群体的参与，并增加攻读研究生学位的本科生人数。将设立STEM挑战奖以及一年一度的夏令营，旨在促进少数族裔社区的高中生参与高等教育STEM学科。大自然创造了生物复合材料，如鲍鱼壳珍珠层、骨骼和海胆，具有与工程材料相比无与伦比的机械和功能特性。这在自然界中是通过具有特定结构和功能的生物分子来实现的，这些生物分子指导着生物材料的生长、微结构、内部界面和宏观性能。受自然的启发，该项目旨在使用一种重组方法来识别特定的生物分子，这些生物分子控制和调节愈合材料的形成、微观结构和性能，并使它们适应破裂的水泥基材料的化学和物理特性，目的是改变自愈合性能。水凝胶是一种聚合物凝胶，其行为可以根据外界刺激进行调节。在本项目中，水凝胶将被合理地设计为生物分子的输送载体，以在水泥基材料中实现自我愈合。这项研究的结果将使我们能够(I)发现与愈合材料(碳酸钙)和水泥表面具有特定结合的生物分子，(Ii)了解生物分子对碳酸钙微观结构和纳米尺度结合的影响，(Iii)揭示水凝胶如何调节水泥材料的微观结构和相组成，以及(Iv)建立生物分子、水凝胶和水泥材料自我愈合性能之间的关系。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The research objective of this Faculty Early Career Development Program (CAREER) project is to acquire a fundamental understanding of a genetic engineering approach to self-healing cementitious materials. Concrete and other cementitious materials are intrinsically brittle and prone to cracking under mechanical and environmental stresses. Therefore, innovative materials with the capability to self-heal after cracks formed are highly desirable in infrastructure. The fundamental insights obtained from the results of this award will advance the development of high performance and smart cementitious materials, contribute to public safety, and benefit national economy by improving the durability and reducing maintenance costs of infrastructure. The educational objectives of this project are to promote participation, especially from under-represented groups, in STEM disciplines and to increase the number of undergraduates who pursue a graduate degree. A STEM Challenge Award, as well as annual summer camps, will be designed with the goal of promoting participation from high school students from minority communities in higher education STEM disciplines.Mother Nature has created biological composite materials, such as nacre of abalone shell, bone, and sea urchin, with unparalleled mechanical and functional properties compared to engineering materials. This is achieved in nature through biomolecules with specific structures and functionalities directing growth, microstructure, internal interfaces, and macroscopic performance of biological materials. Inspired by nature, this project aims to use a recombinant method to identify specific biomolecules that control and tune the formation, microstructure, and properties of the healing material and adapt them to the chemical and physical characteristics of cracked cementitious materials with the goal of transforming the self-healing performance. Hydrogels are polymeric gels and their behavior can be tuned in response to external stimuli. In this project, hydrogels will be rationally designed as a delivery vehicle of biomolecules to impart self-healing in cementitious materials. The results from this research will enable us (i) to discover biomolecules with specific binding to the healing material (calcium carbonate) and cementitious surfaces, (ii) to understand the effect of biomolecules on the microstructure and nanoscale binding of calcium carbonate, (iii) to reveal how hydrogels can modulate the microstructure and phase composition of cementitious materials, and (iv) to establish the relationships between biomolecules, hydrogels, and self-healing performance in cementitious materials.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.