Compressive Performance of Modified Rubber-Toughened Recycled Aggregate Concrete after High Temperature
FENG Wanhui
LI Jinhao
CHEN Yao
YANG Fei
YANG Yongmin
Abstract：The deterioration mechanisms of modified rubber-toughened recycled aggregate concrete(MRRAC)subjected to elevated temperatures ranging from 25℃to 600℃were investigated,with particular focus on mass loss,compressive strength degradation,and toughness evolution.The thermal damage mechanisms at the microscale were comprehensively characterized through scanning electron microscopy(SEM)analysis.The results demonstrates that pretreatment of rubber particles with 10%sodium hydroxide solution significantly enhances the high temperature compressive strenghth and toughness of recycled aggregate concrete after heated at 450℃,with a 58%improvement in compressive strength compared to untreated specimens.A predictive model for the residual compressive strength ratio of MRRAC is developed by incorporating key parameters including the replacement rate of recycled aggregates and rubber content.The fundamental mechanism underlying the improved high temperature resistance is revealed.The softening and decomposition of rubber particles create pore structures within the concrete matrix,which effectively expandes the release channels for internal free water and bound water,thereby reducing the internal-external pressure gradient and mitigating thermal damage.
Keywords：recycled aggregate concreterubber pretreatmentthermal damagecompressive performancemicroscopic morphology
Publication Date：2025-10-30
Online Publishing Date：2025-11-10(First online date of this platform, not the publication date of the document)
Pages：10( 957-965,973 )