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为提升土木工程材料实验教学的前沿性及与工程实践的契合度，该研究将超高性能混凝土（ultra-high performance concrete,UHPC）高温极端工况力学性能测试纳入教学体系，构建融合常规实验与高温力学性能研究的多维度教学模块。通过火灾作用模拟与高温后抗压性能测试的耦合实验设计，系统阐释材料微观结构演变与宏观力学响应的内在关联机制。教学实践表明，该改革方案通过高温实验流程标准化设计，可有效促进学生系统构建极端环境下材料性能演化理论认知，同时强化理论解析能力与工程问题诊断水平。研究成果为土木工程新工科人才培养体系中的实验教学创新提供了可迁移的实施范式。
Abstract：[Objective] To enhance the cutting-edge nature of experimental teaching in civil engineering materials and its integration with engineering practice, this study incorporates the mechanical property testing of ultra-high performance concrete(UHPC) under high-temperature extreme working conditions into a teaching system. A multidimensional teaching module is developed, integrating conventional tests with research on high-temperature mechanical properties. This approach promotes the transformation of experimental teaching from “phenomenon observation” to “mechanism exploration,” helping students cope with challenges in complex engineering environments and addressing the development needs of new engineering disciplines. [Methods] This paper combines the standard temperature-rise fire test with traditional concrete mechanics experiments to comparatively analyze differences in the compressive performance of UHPC cubes following high-temperature exposure. According to the temperature threshold for building fires specified in the ISO-834 standard, three typical exposure temperatures—200 ℃, 400 ℃, and 600 ℃—were selected. Each specimen was held at the target temperature for a constant duration of 60 min. Before compressive testing, physical phenomena in the UHPC specimens after high-temperature exposure were observed, and the mass loss rate was analyzed. The UHPC cube compression test utilized 100-mm× 100-mm×100-mm cube specimens. During testing, the load was applied continuously and uniformly at a rate of 1.4 MPa/s. This research achieved two objectives:(1) the introduction of new instruments and technologies to establish correlations and understanding between the conventional properties of civil engineering materials and their performance in extreme environments;(2) the explanation of the experimental results through a multiscale damage mechanism. [Results] The experimental results show the following. 1) At 400 ℃, the UHPC color deepened to brownish gray. At this point, polypropylene fibers completely melted and decomposed, leaving distinct evaporation traces. 2) At exposure temperatures up to 200 ℃, the mass loss rate of the UHPC specimens was relatively low. However, when the temperature exceeded 400 ℃, the specimen mass loss increased significantly. 3) Following exposure to 200 ℃, the axial compressive failure mode of the UHPC specimens resembled that observed at room temperature. The primary manifestation was the formation of several fine, longitudinal cracks propagating along the specimen sides, connecting the upper and lower surfaces. At this stage, the cracks were relatively fine and few. 4) At an exposure temperature of 200 ℃, the compressive strength of the UHPC cube increased by 2.30% compared with that at room temperature. At 400 ℃, the strength increased by 6.34% compared with that at room temperature. 5) Although the cubic compressive strength of the specimens exposed to 600 ℃ decreased compared with those exposed to 400 ℃, it remained slightly higher than the strength at room temperature. [Conclusions] The coupled experimental design, simulating fire effects and testing compressive performance post-high-temperature exposure, systematically elucidated the intrinsic correlation mechanism between material microstructure evolution and macroscopic mechanical response. The results indicated that the nonlinear attenuation characteristics of UHPC compressive strength with increasing temperature correlated significantly with the reconstruction process of its microscopic phase composition. At 600 ℃, the compressive performance of UHPC diminished significantly compared with that at 400 ℃. Although microstructural damage occurred at 600 ℃, the combined effects of water evaporation and structural optimization enabled the material to retain compressive strength marginally higher than under normal temperature conditions. Furthermore, the high density and low waterbinder ratio of UHPC endowed it with excellent high-temperature damage resistance, contributing to the maintenance of its relatively high compressive strength. Teaching practice demonstrated that this reform, through standardized high-temperature experimental procedures, effectively promoted students' systematic understanding of material property evolution in extreme environments while enhancing their theoretical analysis capabilities and engineering problem diagnosis skills.
[1]付传清,金南国,金贤玉,等.混凝土试件自然裂缝产生装置研制及应用[J].实验技术与管理, 2014, 31(5):75–79.FU C Q, JIN N G, JIN X Y, et al. Development of natural cracks generating device used in concrete specimens and its application[J].Experimental Technology and Management, 2014, 31(5):75–79.(in Chinese)
[2]潘柏州,韦灼彬.原材料对珊瑚砂混凝土抗压强度影响的试验研究[J].工程力学, 2015, 32（增刊1）:221–225.PAN B Z, WEI Z B. Experimental study on effects of raw materials on compressive strength of coral sand concrete[J].Engineering Mechanics, 2015, 32(S1):221–225.(in Chinese)
[3]徐铖基,王小虎,戴雨晴,等.混凝土劈裂损伤和毛细传输过程的原位表征[J].土木工程学报, 2023, 56(8):27–36.XU C J, WANG X H, DAI Y Q, et al. In-situ characterization of concrete splitting damage and capillary transport processes[J].China Civil Engineering Journal, 2023, 56(8):27–36.(in Chinese)
[4]齐会贤.道路面层再生混凝土抗压抗折强度影响因素分析[J].工程建设与设计, 2024(23):139–141.QI H X. Analysis of influencing factors on compressive strength and flexural strength of recycled concrete in pavement layer[J].Construction&Design for Engineering, 2024(23):139–141.(in Chinese)
[5]庄腾腾,徐晓萱,娄益.面向未来的卓越工程人才培养理念及路径:基于2021-2024年全球30份工程教育学会报告的分析[J/OL].高等工程教育研究,(2025-03-17)[2025-03-25]. http://kns.cnki.net/kcms/detail/42.1026.G4.20250506.1538.026.html.ZHUANG T T, XU X X, LOU Y. Concepts and pathways for cultivating future-oriented outstanding engineering talents:An analysis of 30 reports from global engineering education societies(2021-2024)[J/OL]. Research in Higher Education of Engineering,(2025-03-17)[2025-03-25]. http://kns.cnki.net/kcms/detail/42.1026.G4.20250506.1538.026.html.(in Chinese)
[6]李红英.基于问题中心的土木工程材料实验教学设计优化[J].高教学刊, 2025, 11（增刊1）:47–50.LI H Y. Optimization of experimental teaching design for civil engineering materials based on problem-centered approach[J].Journal of Higher Education, 2025, 11(S1):47–50.(in Chinese)
[7]丁铸,孙坤,刘伟,等.土木工程材料实验教学组织与实施[J].实验技术与管理, 2008, 25(1):116-118, 128.DING Z, SUN K, LIU W, et al. Organization and implementation of experimental teaching for civil engineering materials[J].Experimental Technology and Management, 2008, 25(1):116–118, 128.(in Chinese)
[8]王圣程,禄利刚,张朕,等.基于科研资源的土木工程材料实验教学拓展探索[J].实验技术与管理, 2018, 35(4):199–202.WANG S C, LU L G, ZHANG Z, et al. Exploration on expansion of experimental teaching for civil engineering materials based on scientific research resources[J]. Experimental Technology and Management, 2018, 35(4):199–202.(in Chinese)
[9]朱洪波.水泥基材料开发性实验课程设计[J].实验室研究与探索, 2018, 37(6):188–191.ZHU H B. Developmental experimental course design of cement-based materials[J]. Research and Exploration in Laboratory, 2018, 37(6):188–191.(in Chinese)
[10]李福海,靳贺松,王江山,等.土木工程材料课程实验创新探讨:以纤维水泥基材料抗拉综合性试验为例[J].实验室研究与探索, 2020, 39(1):185–190.LI F H, JIN H S, WANG J S, et al. Discussion on the innovation of experimental teaching of building materials:A case study on tensile test of fiber-reinforced cementitious composites[J].Research and Exploration in Laboratory, 2020, 39(1):185–190.(in Chinese)
[11]段海娟,王英.基于ADDIE模式的土木工程材料实验课混合式教学探索[J].实验室研究与探索, 2021, 40(8):159–162.DUAN H J, WANG Y. Blended teaching of civil engineering materials experiment course based on ADDIE model[J].Research and Exploration in Laboratory, 2021, 40(8):159–162.(in Chinese)
[12]万朝均.高性能混凝土研究型实验项目的设置与实践[J].实验室研究与探索, 2011, 30(7):337–339.WAN C J. Design and practice of research-oriented experimental projects for high-performance concrete[J]. Research and Exploration in Laboratory, 2011, 30(7):337–339.(in Chinese)
[13]张清华,贾东林,卜一之.基于高性能材料实验的学生创新能力培养[J].实验技术与管理, 2019, 36(1):16–19, 32.ZHANG Q H, JIA D L, BU Y Z. Cultivation of students'innovative ability based on high-performance material experiments[J]. Experimental Technology and Management,2019, 36(1):16–19, 32.(in Chinese)
[14]吴香国,曹景杰,赵新宇.虚拟仪器的超高强混凝土结构性能测试[J].实验科学与技术, 2012, 10(1):52–55.WU X G, CAO J J, ZHAO X Y. Performance testing of ultrahigh strength concrete structures based on virtual instruments[J].Experiment Science and Technology, 2012, 10(1):52–55.(in Chinese)
[15]张敏,高寒,黄康华,等.“智能混凝土及检测系统”实验设计[J].实验技术与管理, 2021, 38(4):48–51, 56.ZHANG M, GAO H, HUANG K H, et al. Experimental design of“intelligent concrete and detection system”[J]. Experimental Technology and Management, 2021, 38(4):48–51, 56.(in Chinese)
[16]谭春雷,邓宇,崔李三,等. VR技术在土木工程材料实验课程中的应用效果[J].教育观察, 2023, 12(16):91–94.TAN C L, DENG Y, CUI L S, et al. Application effect of VR technology in civil engineering materials experiment course[J].Journal of Educational Observation, 2023, 12(16):91–94.(in Chinese)
[17]张庆宇,张博,吴守军,等.冻融循环下掺合料对UHPC强度影响规律研究[J].水利与建筑工程学报, 2024, 22(1):198–204.ZHANG Q Y, ZHANG B, WU S J, et al. Effect of admixtures on strength of UHPC under freeze-thaw cycles[J]. Journal of Water Resources and Architectural Engineering, 2024, 22(1):198–204.(in Chinese)
[18]杨婷,杨烨凯,刘中宪,等.高温后超高性能混凝土力学性能试验研究[J].工程力学, 2025,42(4):97–109.YANG T, YANG Y K, LIU Z X, et al. Experimental study on mechanical properties of ultra-high performance concrete after high-temperature exposure[J]. Engineering Mechanics, 2025,42(4):97–109.(in Chinese)
[19]梅葵花,亢文波,刘洋,等.氯盐环境下预损伤UHPC-HPC组合梁抗弯性能[J].交通运输工程学报, 2024, 24(1):117–130.MEI K H, KANG W B, LIU Y, et al. Flexural behavior of predamaged UHPC-HPC composite beams under chloride salt environment[J]. Journal of Traffic and Transportation Engineering,2024, 24(1):117–130.(in Chinese)
[20]全国混凝土标准化委员会.活性粉末混凝土:GB/T 31387—2015[S].北京:中国标准出版社, 2015.National Concrete Standardization Technical Committee. Reactive powder concrete:GB/T 31387—2015[S]. Beijing:Standards Press of China, 2015.(in Chinese)
[21]中国建筑科学研究院.普通混凝土力学性能试验方法标准:GB/T 50081—2002[S].北京:中国建筑工业出版社, 2003.China Academy of Building Research. Standard for test methods of mechanical properties of ordinary concrete:GB/T 50081—2002[S]. Beijing:China Architecture&Building Press, 2003.(in Chinese)
[22] ZHANG X Y, CAI S H, WANG Z H, et al. Research on mechanical properties of ultra-high performance fiber reinforced cement-based composite after elevated temperature[J]. Composite Structures, 2022, 291.
Basic Information:
DOI：10.16791/j.cnki.sjg.2025.09.030
China Classification Code:TU528-4;G642.423
Citation Information:
[1]何康,刘崇阳,雷斌.基于高温极端工况的UHPC力学性能实验教学拓展探索[J].实验技术与管理,2025,42(09):240-246.DOI:10.16791/j.cnki.sjg.2025.09.030.
Fund Information:
国家自然科学基金项目(52308172); 江西省自然科学基金项目(20242BAB25291,20232BAB214075); 教育部产学合作协同育人项目(202002157007)