Enhancement mechanism of waste tire steel fibers on the performance of ultra-high performance concrete
GAO Guoqi
Abstract：This study systematically investigates the influences of waste tire-derived steel fibers(WT-SF)and conventional copper-coated steel fibers(SF)on the mechanical properties of ultra-high-performance concrete(UHPC)through comparative experimentation.Key findings reveal that at a 2.0%volume fraction,WT-SF enhances UHPC compressive strength by 20.7%(140.1 MPa)compared to plain UHPC at 28 d,attributable to its distinctive surface roughness and geometric irregularity.However,both compressive strength and four-point flexural toughness index of WT-SF-reinforced UHPC remain inferior to SF counterparts at equivalent fiber volume fraction.Significantly,the geometric irregularity of WT-SF significantly improves the axial tensile strain energy of UHPC.It is recommended to prioritize the use of WT-SF in the main tensile components of UHPC(such as seismic nodes,blast resistant components,and anchorage zones),and control the dosage to 1.5%～2.0%.
Keywords：ultra-high performance concretewaste tire steel fibersflexural toughnessaxial tensile performance
Publication Date：2025-07-25
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 76-79,101 )