Strength deterioration model of recycled coarse aggregate seawater-sea sand concrete after freeze-thaw cycles
YU Shuang
HE Dong
Abstract：This study investigates the mechanical degradation of recycled aggregate seawater sea sand concrete after freeze-thaw cycles.Through rapid freeze-thaw tests,the mass loss rate,relative dynamic elastic modulus,compressive strength,and split-ting tensile strength of concrete were tested when granite crushed stone NS was replaced by recycled concrete coarse aggregate RC and recycled brick coarse aggregate RB at different substitution rates.Results indicate that freeze-thaw damage severity fol-lows the order:RB>RC>NS.RB aggregates had approximately 2.2～2.7 times greater impact on compressive strength degradation and 1.5 times greater impact on splitting tensile strength degradation compared to RC aggregates.Increasing the substitution rate exacerbated the deterioration of all performance metrics in recycled aggregate specimens.Proposed models for compressive strength and splitting tensile strength incorporate four parameters(freeze-thaw cycles,aggregate crushing index,water absorption,and substi-tution rate),with calculation errors<20%.
Keywords：recycled aggregateseawater sea sand concretefreezing and thawingcompressive strengthsplitting tensile strength
Publication Date：2025-08-25
Online Publishing Date：2025-09-12(First online date of this platform, not the publication date of the document)
Pages：8( 88-95 )