摘要
该文提出了一种龄期相关的混凝土尺寸效应断裂模型。基于现有模型建立可用于确定试件尺寸和缝高比变化时混凝土断裂破坏的尺寸效应模型演化形式;结合模型参数的时变规律,提出一种考虑龄期影响的尺寸效应断裂模型;采用文献中试件龄期、尺寸和缝高比变化的混凝土断裂试验结果验证模型的适用性。研究发现:为保证模型对于特定龄期混凝土断裂破坏预测的精度,建议模型所用材料常数至少由3组且最大与最小等效裂缝长度之比不小于4的混凝土试件断裂试验结果确定。指数函数形式可较好地描述混凝土材料常数的时变特性。龄期相关的尺寸效应模型可准确预测试件龄期、尺寸和缝高比变化时混凝土构件的断裂破坏。
Proposes an age-dependent size effect fracture model for concrete.Based on the existing models,an evolution form of the size effect model is established to determine the fracture failure of concrete specimens with variable sizes and ratios of crack to height.Combined with the time-varying characteristics of model parameters,a size effect fracture model considering the age effect is proposed.The applicability of the model is verified by the concrete fracture test results in the literature with different specimen ages,sizes and ratios of crack to height.In order to ensure the accuracy of the model predictions of concrete fracture failure at a specific age,it is recommended that the material constants used in the model should be determined from fracture test results of at least 3 groups of concrete specimens,with the ratio of maximum to minimum equivalent crack length not less than 4.The exponential function form can well describe the time-varying characteristics of concrete material constants.The age-dependent size effect model can accurately predict the fracture failure of concrete members with variable ages,sizes and ratios of crack to height.
作者
高小峰
杨程
李庆斌
胡昱
谭尧升
周欣竹
GAO Xiao-feng;YANG Cheng;LI Qing-bin;HU Yu;TAN Yao-sheng;ZHOU Xin-zhu(College of Civil Engineering,Zhejiang University of Technology,Hangzhou 310023,China;State Key Laboratory of Hydroscience and Engineering,Tsinghua University,Beijing 100084,China;China Three Gorges Construction Engineering Corporation,Chengdu 610041,China;China Three Gorges Group Corporation,Beijing 100038,China)
出处
《工程力学》
EI
CSCD
北大核心
2024年第3期26-38,共13页
Engineering Mechanics
基金
国家自然科学基金项目(52009123,51839007)
浙江省自然科学基金项目(LY22E090004)
中国长江三峡集团有限公司科研项目(BHT/0809)。
关键词
混凝土结构
断裂参数
尺寸效应
时变特性
断裂破坏
concrete structure
fracture parameters
size effect
time-varying characteristics
fracture failure
