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| 高养护压力对混凝土力学性能及微观结构的影响研究 |
| Influence of high curing pressure on the mechanical performance and micro-scale characterization of concrete |
| 投稿时间：2025-05-16 修订日期：2025-12-02 |
| DOI： |
| 中文关键词: 混凝土 养护压力 力学性能 微观形貌 水化产物 |
| 英文关键词: concrete, curing pressure, mechanical properties, microscale structure, hydration products |
| 基金项目:国家自然科学基金资助项目(52479131) |
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| 摘要点击次数: 38 |
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| 中文摘要: |
| 防渗墙混凝土浇筑后需承受上部固壁泥浆压力影响,其性能及微观结构与常规养护下混凝土差异较大。采用宏-微观试验技术手段,探究了高养护压力条件下混凝土力学性能及微观结构的演变过程。结果表明:压力作用下试样初始加载阶段明显缩短,弹性阶段曲线更陡峭,抗压强度和弹性模量分别增加了35.60%和44.51%,整体力学性能更好。混凝土内部水化产物胶结更紧密,形成更大尺寸的团聚体,骨架发展更充分,有效抑制了试样内部微裂缝的萌生。混凝土试件中孔径分布呈现由大向小的演化趋势,孔隙结构得到了有效细化。体系内的结合水含量和水化程度显著增加,养护压力有利于加速水泥矿物颗粒溶解反应,促进高密度水化产物沉淀析出。在养护压力作用下,混凝土体系内硅氧链聚合程度更高,层间结合水与水化产物之间的结合更强,硅氧四面体结构发展成高连通性结构。 |
| 英文摘要: |
| Due to the pressure exerted by the self-weight of support slurry, the cut-off wall concrete exhibits distinct characteristics compared to concrete cured under standard conditions. This research investigated the evolution of mechanical performance and micro-structure of concrete hardened? under high curing pressure via a series of multi-scale tests. The results showed that under the high curing pressure, the initial loading stage of the specimens was shortened, and the elastic phase of the stress–strain curve became steeper. The compressive strength and elastic modulus increased by 35.60% and 44.51%, respectively, indicating an overall enhancement in mechanical performance. In micro-scale, sample cured in pressure exhibited a denser microstructure with highly developed solid skeleton than that cured in ambient condition, which has inhibited the growth of crack. The pore size distribution within the pressurized specimens performed a refinement trend from larger to smaller pores, indicating an effective densification of the pore structure. The content of bound water and the degree of hydration were significantly increased under curing pressure, which facilitated the dissolution of cement grains and promoted the precipitation of high-density hydration products. Furthermore, high curing pressure enhanced the polymerization of silicate chains within the hydration products, strengthened the bonding between interlayer water and hydration products, and promotes the development of a highly connected silicate tetrahedral network structure. |
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