Accelerating Use of Sustainable Materials in Transportation Infrastructure

With the push towards sustainable design of highway infrastructure systems owners have shown interest in leveraging materials with minimal environmental impacts and extended service lives. Within this emphasis most efforts on sustainable material design have focused on improving the durability of materials; however, an alternative trajectory for sustainable material design includes the development of materials with increased functionality to include features such as self-healing, self-cleaning, and self-sensing. This investigation focuses primarily on this last level of functionality within cementitious composites, such that concrete can be designed to function as a structural component, but with the added functionality of distributed sensing continuum. Over the past two decades, numerous research studies have been conducted to explore behavior of self-sensing cementitious composites with different functional fillers. Most of these studies investigated the use of fillers such as carbon nanofiber (CNF), carbon black, and carbon nanotubes (CNTs) in cement composites to develop a multifunctional material. More recently, graphene nanoplatelets (GNPs), which have very thin but wide aspect ratio, are drawing the graphene market due to their advantages such as ease of processing and excellent material properties at a very low cost. The application of two-dimensional GNPs in cementitious composites has yet to gain widespread attention. This report describes an investigation on the the self-sensing capabilities of GNP-reinforced hydraulic Portland cement composites. In particular, the effects of GNP content on the electrical properties and piezoresistive characteristics of mortar specimens are explored. In addition, a simple fabrication method that does not require special treating procedures such as ultrasonication and chemical (covalent) treatments for the dispersion of GNPs is pursued. The GNPs used in this study have an average thickness of 8 nanometers and a diameter of 25 microns. Standard prismatic mortar specimens containing different GNP concentrations were prepared using three different mixing procedures. The resistivity of the specimens was measured using a four-point probe method. Finally, the piezoresistive response of GNP-reinforced cement composites was evaluated under cyclic compressive loads. The GNP-reinforced mortar specimens exhibited good piezoresistive behavior under cyclic compressive loads when the GNP ratios exceed 5%.

Language

  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Figures; Photos; References; Tables;
  • Pagination: 36p

Subject/Index Terms

Filing Info

  • Accession Number: 01663179
  • Record Type: Publication
  • Contract Numbers: DTRT13-G-UTC33
  • Files: UTC, NTL, TRIS, ATRI, USDOT
  • Created Date: Feb 8 2018 10:16AM