ACRP Graduate Student Paper - Optimization of Cellular Concrete Microstructure for Improved Impact Resistance

Engineered Material Arresting System (EMAS) is a cellular concrete material currently used as passive aircraft arresting systems at airports around the United States and abroad. Its cellular structure crushes upon impact helping to absorb energy and create drag resistance. Energy absorbed during crushing is defined by the load-deformation response curve, in which a plateau is indicative of crushing behavior at a near-constant load. At the microstructural level, the energy absorbed from crushing is a combination of elastic buckling, plastic yield, and brittle fracture of the cellular microstructure. Therefore, optimization of the cellular structure (e.g., bubble size and distribution) is paramount to the overall performance of these systems. This study makes use of microstructural investigations, quasi-static indentation, and drop weight testing to investigate the performance of cellular concrete with varied microstructures. The results show that while density (air content) has traditionally been considered the main predictor of overall performance, the nature of the cellular structure, owing to the use of different foaming agents, can be a useful design tool. Thus, adding another important consideration in the design of impact-resistant infrastructure. Given this finding, a new set of design guidelines are presented in this paper. The goal of this work is to inform better design of impact-resistant infrastructure by identifying cellular concrete microstructures which lead to optimal energy absorption in low-velocity impact events, such as aircraft overruns.

Language

  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; Photos; References; Tables;
  • Pagination: 13p

Subject/Index Terms

Filing Info

  • Accession Number: 01764433
  • Record Type: Publication
  • Report/Paper Numbers: TRBAM-21-00377
  • Files: TRIS, TRB, ATRI
  • Created Date: Dec 23 2020 11:05AM