摘要
低热水泥混凝土在中国特高拱坝建设中已全面应用。为确定低热水泥混凝土早龄期断裂性能发展规律,设计10,20,40℃3种养护温度,3,7,14,28 d 4种龄期,开展了不同养护温度下低热水泥混凝土楔入劈拉断裂试验,并依据试验结果采用成熟度理论分析断裂参数与等效龄期间的关系。结果表明:在10~40℃范围内,相同龄期低热水泥混凝土的起裂断裂韧度、失稳断裂韧度和断裂能均随养护温度的增大而增大;基于成熟度理论的等效龄期计算公式和断裂参数-成熟度的对数函数形式均可较好地描述低热水泥混凝土早龄期断裂性能发展规律。研究成果可为大坝结构开裂风险分析与安全评定过程中可靠断裂参数的取值提供依据。
Low-heat cement concrete has been fully applied in the construction of extremely high arch dam in China.In order to determine the development law of the fracture performance of low-heat cement concrete at early age,three curing temperatures(10℃,20℃,40℃)and four curing ages(3,7,14,28 d)were designed to break low-heat cement concrete,and the relationship between fracture parameters and equivalent age was analyzed by maturity theory according to the test results.The results showed that the initial fracture toughness,unstable fracture toughness and fracture energy of the concrete increased in 10~40℃.The calculation formula of equivalent age based on the maturity theory,and the log function form of fracture parameter-maturity can better describe the development law of the fracture performance of low-heat cement concrete at early-age.The research results can provide a basis for reliable fracture parameters value determination in the risk analysis and safety evaluation of dam structure.
作者
刘志洪
胡昱
邬昆
杨宁
谭尧升
高小峰
LIU Zhihong;HU Yu;WU Kun;YANG Ning;TAN Yaosheng;GAO Xiaofeng(Faculty of Electric Power Engineering,Kunming University of Science and Technology,Kunming 650500,China;State Key Laboratory of Hydroscience and Engineering,Tsinghua University,Beijing 100084,China;China Three Gorges Projects Development Co.,Ltd.,Chengdu 610041,China;College of Civil Engineering,Zhejiang University of Technology,Hangzhou 310023,China)
出处
《人民长江》
北大核心
2022年第1期175-181,共7页
Yangtze River
基金
国家自然科学基金项目(51839007,52009123)
水沙科学与水利水电工程国家重点实验室开放研究基金资助课题项目(sklhse-2020-C-04)
中国长江三峡集团有限公司科研项目(BHT/0809,WDD/0427,BHT/0806)。
关键词
低热水泥
混凝土
断裂参数
养护温度
成熟度
楔入劈拉断裂试验
高拱坝
low-heat cement
concrete
fracture parameters
curing temperature
maturity
spilitting tensile test high arch dam
