砂漠砂と表面改質廃ゴムを混入したコンクリートの力学性能および限定的な埋め込み炭素評価

Unofficial AI-generated summary based on the public title and abstract. Not an official translation.

🔬研究者:Provides empirical regression models and a TOPSIS framework for multi-criteria optimisation of low-carbon concrete mixes, though carbon benefits are marginal.

🏢実務担当者:Offers a quantitative basis for selecting RDSC mixes balancing mechanical performance and carbon intensity, useful for sustainable construction procurement.

🏛政策担当者:Highlights the need for standards that distinguish resource-conservation benefits from actual carbon reduction in construction material policies.

The rapid depletion of natural river sand resources and the increasing accumulation of waste tyres have intensified the demand for sustainable alternative materials that can simultaneously reduce resource consumption and environmental burdens in the construction industry. Although desert sand and waste rubber have each attracted considerable research attention as alternative aggregates in concrete, their combined effects on the mechanical performance and environmental sustainability of cement-based composites remain insufficiently understood. In particular, the synergistic influence of desert sand and surface-modified rubber particles on mechanical properties and limited carbon emissions has not been fully elucidated. In this study, rubberised desert sand concrete (RDSC) was developed by simultaneously incorporating desert sand and surface-modified waste rubber as partial replacements for conventional fine aggregates. A total of 16 concrete mix proportions were designed, with desert sand replacement ratios ranging from 0% to 60% and modified rubber contents ranging from 0% to 15%. The mechanical properties of the prepared composites were evaluated through cubic compressive strength, axial compressive strength, flexural strength, and static elastic modulus tests. In addition, the embodied carbon contributions of each constituent material were estimated within the defined raw material stage in accordance with GB/T 51,366–2019, and empirical relationships between the mix proportion parameters and the measured mechanical responses were established. The results indicate that replacing natural river sand with 20%–40% desert sand can enhance the compressive strength, while an appropriate amount of surface-modified rubber can increase the measured peak flexural strength. The R-DS20-10 mixture achieved the highest measured peak flexural strength. Through entropy-weighted TOPSIS evaluation of three strength-normalised carbon intensity indicators, R-DS20-0 was found to rank highest within the defined decision matrix with Ci = 0.918, and maintained the top rank under equal-weight conditions. The selected empirical regression models all exhibited coefficients of determination higher than 0.85 within the investigated dataset and parameter ranges. The difference in embodied carbon among the mixtures was relatively small, with a maximum variation of approximately 0.17%. Therefore, the core value of this material system lies in its potential to conserve natural river sand and utilise waste rubber, rather than in achieving substantial carbon reduction. These findings provide a quantitative basis for selecting RDSC mixtures according to mechanical performance and carbon intensity priorities.

• semanticscholar https://www.nature.com/articles/s41598-026-71166-1_reference.pdffirst seen 2026-10-09 05:26:02 · last seen 2026-10-10 05:46:53