Tuijin Jishu/Journal of Propulsion Technology ISSN: 1001-4055 Vol. 44 No. 6 (2023) __________________________________________________________________________________ 6360 Influence of Nanomaterials on the workability of Cement-based Concrete _ A Critical Review Basavaraj Gudadappanavar 1 , Veeresh B Karikatti 2 , Brijbhushan S. 3 1 Assistant Professor, Civil Engineering, SDM College of Engineering & Technology, Dharwad, Karnataka- 580 002 2 Associate Professor Department of Civil Engineering, K. L. E. Institute of Technology, Hubballi 3 Assistant Professor, Department of Civil Engineering (Construction Technology), Visvesvaraya Technological University, Centre for Postgraduate Studies, Kalaburagi - 585105, Karnataka Kalaburagi Abstract The development of nanotechnology has led to the emergence of nanomaterials as potential admixtures suitable for the enhanced workability of cement-based concrete. This review paper being presented is an overview of the latest research development on the use of nanomaterials and their influence on the workability of cement-based concrete, factors affecting workability, mechanism, potential applications and economic aspects. A detailed discussion on the three main types of nanoenhancers such as nanosilicates, carbon nanotubes and fullerenes and their properties in capable of modifying concrete workability has been carried out. In addition, the effect of particle size and concentration on the properties of the concrete has also been examined. Furthermore, this review exposes some of the key aspects of nano-admixtures applications in enhancing the workability of cement-based concrete. Keywords: Nanomaterials, Cement-based concrete, Workability, Nanosilicates, Carbon nanotubes, Fullerenes Introduction: The use of nanomaterials in the construction industry has gained significant attention in recent years due to their potential to improve the workability and properties of cement-based concrete. Nanomaterials, which are defined as materials with at least one dimension less than 100 nanometers, exhibit unique characteristics that differ from their bulk counterparts. These materials possess a high surface-to-volume ratio, increased reactivity, and enhanced mechanical properties, which make them an attractive addition to cement-based materials. The incorporation of nanomaterials in concrete has shown promise in enhancing various properties, such as strength, durability, and rheological behavior. This can be attributed to the ability of nanomaterials to fill and reinforce the pores and voids within the concrete matrix, leading to a denser microstructure. Furthermore, the small size of these materials allows them to penetrate deeper into the concrete, improving the interfacial transition zone and interparticle bonding. Consequently, the overall workability and performance of cement-based concrete can be significantly influenced by the addition of nanomaterials, making it an area of great interest for research and development in the construction industry. Nanomaterial Nanomaterials can be defined as materials with at least one dimension in the nanoscale range, typically between 1 to 100 nanometers. These materials possess unique properties and characteristics due to their small size and large surface area-to-volume ratio. Nanotechnology has enabled the design and synthesis of nanomaterials with tailored properties and functionalities that are not found in their bulk counterparts. Nanomaterials can be categorized into various types, such as nanoparticles, nanofibers, nanowires, and nanocomposites, based on their structure and composition. The small size of nanomaterials allows for enhanced mechanical, electrical, thermal,