Wang Yuntian, Xie Songlin, Li Yushu, Yang Min, Chen Qiuling, Huang Lijuan, Hu Danping, Li Sheng
School of Urban Construction, Chengdu Polytechnic, Chengdu 610041, China.
Sichuan Thermoelectric Materials and Devices Application Engineering Research Center, Chengdu 610041, China.
Materials (Basel). 2025 Mar 31;18(7):1575. doi: 10.3390/ma18071575.
Steam curing is a widely used method in the production of industrial precast concrete but it often leads to thermal damage that negatively impacts the material's long-term durability and mechanical strength. The use of supplementary cementitious materials (SCMs) has shown considerable promise in improving pore structure and alleviating these adverse effects. This study employs high-resolution X-ray computed tomography (X-CT) to thoroughly assess how steam curing temperatures and various subsequent curing regimes influence the pore characteristics of mortars containing high volumes of mineral admixtures. The results shows that steam-cured specimens under water curing (ST8012-WA) achieved a compressive strength of 51.72 MPa and flexural strength of 5.85 MPa, representing improvements of 9% and 19.8%, respectively, compared to natural curing (ST8012-NA: 47.32 MPa and 4.88 MPa). The standard-cured specimen (SD) exhibited the highest compressive strength of 54.18 MPa, highlighting the detrimental effects of elevated steam curing temperatures. The findings reveal that higher steam curing temperatures result in increased porosity and decreased mechanical strength, challenges that can be effectively mitigated through appropriate postcuring techniques. Notably, water curing following steam curing proves especially effective in reducing pore size variability and improving the material's durability. This research offers new insights into the intricate relationships among curing temperature, pore morphology, and mechanical performance, providing practical recommendations to optimize the quality and longevity of steam-cured precast concrete components.
蒸汽养护是工业预制混凝土生产中广泛使用的方法，但它常常导致热损伤，对材料的长期耐久性和机械强度产生负面影响。使用辅助胶凝材料（SCMs）在改善孔隙结构和减轻这些不利影响方面已显示出可观的前景。本研究采用高分辨率X射线计算机断层扫描（X-CT）来全面评估蒸汽养护温度和各种后续养护制度如何影响含有大量矿物掺合料的砂浆的孔隙特征。结果表明，水养护下的蒸汽养护试件（ST8012-WA）的抗压强度为51.72MPa，抗折强度为5.85MPa，与自然养护（ST8012-NA：47.32MPa和4.88MPa）相比，分别提高了9%和19.8%。标准养护试件（SD）的抗压强度最高，为54.18MPa，突出了蒸汽养护温度升高的不利影响。研究结果表明，较高的蒸汽养护温度会导致孔隙率增加和机械强度降低，这些挑战可以通过适当的后养护技术有效缓解。值得注意的是，蒸汽养护后的水养护在减少孔径变异性和提高材料耐久性方面特别有效。本研究为养护温度、孔隙形态和机械性能之间的复杂关系提供了新的见解，为优化蒸汽养护预制混凝土构件的质量和寿命提供了实用建议。
