Abstract
Ultra-high performance concrete (UHPC) is gaining popularity for large-scale applications due to its superior mechanical performance and durability. However, the extent of large applications remains limited because of the high cost and carbon footprint of UHPC components like steel fibers. This study aims to incorporate different types of recycled steel fibers (RSF) from landfill tires as an alternative to manufactured steel fibers (MSF), specifically in semi- or non-proprietary UHPC mixtures, to realize and validate an ultra-economical UHPC solution. An average compressive strength of 18.9 ksi was developed for UHPC RSF, a 9–13 % decrease compared to UHPC MSF. However, fiber aspect ratio and volume play a significant role in tensile and flexural performance, and the recommended fiber volume should be around 6.3 % and 1.6 % for Type I and II RSF, respectively. The truck mixing confirms the application of reduced RSF volume in large-scale mixing, which demonstrated acceptable mechanical performance. Overall, the study outlines the opportunities and challenges of using RSF in scalable UHPC but also demonstrates, for the first time, the validity of RSF with a high aspect ratio and recommends the proper RSF dosage for comparable mechanical behavior as using high-end MSF.
Original language | English (US) |
---|---|
Article number | 111582 |
Journal | Journal of Building Engineering |
Volume | 99 |
DOIs | |
State | Published - Apr 1 2025 |
Keywords
- Cracking behavior
- Economical UHPC
- Recycled steel fibers
- Strain/stress localization
ASJC Scopus subject areas
- Civil and Structural Engineering
- Architecture
- Building and Construction
- Safety, Risk, Reliability and Quality
- Mechanics of Materials