Differences in microscopic properties of two major interfacial transition zones in interface between new and old concrete

IF 2.7 4区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Letters Pub Date : 2025-03-28 DOI:10.1016/j.matlet.2025.138471

Zhenghao Fu , Hongbing Zhu , Zhengfa Guo

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引用次数: 0

Abstract

At present, there are few microscopic explanations for the fact that excessive interfacial roughness is detrimental to interfacial bonding strength between new and old concrete. To enrich this research field, interfacial transition zone between old concrete’ aggregates and new concrete (ITZ-A) and interfacial transition zone between old concrete’ cement mortar and new concrete (ITZ-C) were as research subjects in this study. Their differences were investigated using scanning electron microscopy and energy dispersive spectroscopy. Comparative analysis revealed significant differences in three critical micro parameters: calcium-to-silicon content ratio (Ca/Si), the percentage of enriched region of CH and C-S-H, and microporosity characteristics. ITZ-C has 16.39 % less Ca/Si, 64.11 % less enriched regions of CH, 49.86 % more enriched regions of C-S-H, and 30.96 % less porosity than the ITZ-A. Moreover, ITZ-C porosity was dominated by sub-0.1 μm² micropores (45.26 % of total pore area), while ITZ-A exhibited predominant 1–5 μm² mesopores (39.08 % of total pore area). Based on the denseness and integrity of the matrix of the microstructure, the microscopic properties of ITZ-C were superior to those of ITZ-A.

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来源期刊

Materials Letters 工程技术-材料科学：综合

CiteScore

5.60

自引率

3.30%

发文量

1948

审稿时长

50 days

期刊介绍： Materials Letters has an open access mirror journal Materials Letters: X, sharing the same aims and scope, editorial team, submission system and rigorous peer review. Materials Letters is dedicated to publishing novel, cutting edge reports of broad interest to the materials community. The journal provides a forum for materials scientists and engineers, physicists, and chemists to rapidly communicate on the most important topics in the field of materials. Contributions include, but are not limited to, a variety of topics such as: • Materials - Metals and alloys, amorphous solids, ceramics, composites, polymers, semiconductors • Applications - Structural, opto-electronic, magnetic, medical, MEMS, sensors, smart • Characterization - Analytical, microscopy, scanning probes, nanoscopic, optical, electrical, magnetic, acoustic, spectroscopic, diffraction • Novel Materials - Micro and nanostructures (nanowires, nanotubes, nanoparticles), nanocomposites, thin films, superlattices, quantum dots. • Processing - Crystal growth, thin film processing, sol-gel processing, mechanical processing, assembly, nanocrystalline processing. • Properties - Mechanical, magnetic, optical, electrical, ferroelectric, thermal, interfacial, transport, thermodynamic • Synthesis - Quenching, solid state, solidification, solution synthesis, vapor deposition, high pressure, explosive