温度对水工沥青混凝土强度及剪胀特性的影响试验研究
Experimental Study on the Influence of Temperature on Strength and Dilatancy of Hydraulic Asphalt Concrete
次仁云旦 1王柳江 2扎西顿珠 1毛航宇 2李瑞平2
作者信息
- 1. 西藏自治区水利电力规划勘测设计研究院,拉萨 850000
- 2. 河海大学 水利水电学院,南京 210098;大坝长效特性及环保修复技术中西联合实验室,南京 210098
- 折叠
摘要
为了解温度变化对沥青混凝土强度及剪胀特性的影响,开展了-1、5、10、15℃下的沥青混凝土三轴剪切试验.试验结果表明:沥青混凝土的强度变形特性与温度有密切关系,负温时,表现出明显的应变软化和剪胀性,随着温度的升高,应力-应变曲线转变为应变硬化型,且剪胀性减弱;沥青混凝土抗剪强度随温度升高而减小,且黏聚力的降低幅度明显大于内摩擦角,当温度从-1 ℃升高到15 ℃时,内摩擦角减小了4.7°,而黏聚力由1.11 MPa减小到0.28 MPa;沥青混凝土剪胀角随轴向应变增大而增大,并趋于稳定,两者关系可采用双曲线函数进行拟合;双曲线模型参数与温度有较好的相关性,可进一步考虑剪胀角随温度的变化情况.研究成果可为沥青混凝土的热-力耦合本构模型建立提供参考.
Abstract
To investigate the impact of temperature on the strength and dilatancy behaviors of hydraulic asphalt con-crete,triaxial shear tests were conducted on asphalt concrete samples at controlled temperatures of-1 ℃,5 ℃,10 ℃,and 15 ℃.The results demonstrate a strong correlation between temperature and the mechanical response of the asphalt concrete.At temperatures below 0 ℃,the samples exhibit evident strain softening and dilatancy behav-iors.However,as temperature rises,the strain softening transforms into strain hardening,and the degree of dilatan-cy decreases.Moreover,the shear strength of asphalt concrete reduces with increasing temperature,with the de-crease in cohesion being more pronounced compared to the internal friction angle.Specifically,as temperature rises from-1 ℃ to 15 ℃,the internal friction angle declines by 4.7°,while cohesion drops from 1.11 MPa to 0.28 MPa.Additionally,the dilatancy angle expands with the increase of axial strain and eventually stabilizes,exhibiting a suitable fit using a hyperbolic function.Remarkably,the parameters of the hyperbola model demonstrate a strong correlation with temperature,making them useful for developing a thermal-mechanic constitutive model for asphalt concrete.
关键词
沥青混凝土/温度/强度特性/剪胀特性/堆石坝Key words
asphalt concrete/temperature/strength/dilatancy/rockfill dam引用本文复制引用
基金项目
国家重点研发计划项目(2022YFE0105000)
国家自然科学基金项目(51979091)
国家自然科学基金项目(52009036)
中央高校基本科研业务费专项(B210204021)
出版年
2024
国家科技期刊平台
NSTL
维普
万方数据