In order to effectively assess the mechanical properties of concrete with freeze-thaw and seawater erosion, tests about basic mechanical properties of concrete after freeze-thaw and seawater erosion are conducted base...In order to effectively assess the mechanical properties of concrete with freeze-thaw and seawater erosion, tests about basic mechanical properties of concrete after freeze-thaw and seawater erosion are conducted based on the large-scale static and dynamic stiffness servo test set. 50, 100, 200 and 300 cycles of freeze-thaw cycling are made on normal concrete, and the artificial seawater is produced. The reasonable wet and dry accelerate system is selected. 10, 20, 30, 40, 50 and 60 cycles of wet and dry cycling are made to concrete after freeze-thaw cycling. The degeneration law of the concrete elastic modulus and compressive strength is studied. The Ottosen tri-axial strength criterion considering cycles of freeze-thaw and wet and dry cycling is deduced based on uniaxial mechanical properties of concrete and damage theory. Experimental results show that with the increase in the number of wet and dry cycles and freeze-thaw cycles, the concrete axial compressive strength and the elastic modulus decline gradually. Tensile and compressive meridians of concrete shrink gradually. The research can be referenced for anti-crack design of actual structures eroded by seawater at cold regions.展开更多
为研究不同冻融循环次数加载下混凝土的力学性能,利用大型多功能液压伺服三轴仪对双向应力状态下不同冻融次数(0、20、40次)和不同侧压力(0、0.06 f c、0.12 f c、0.18 f c、0.24 f c)的混凝土进行了静态(应变速率10-5/s)压缩试验,建立...为研究不同冻融循环次数加载下混凝土的力学性能,利用大型多功能液压伺服三轴仪对双向应力状态下不同冻融次数(0、20、40次)和不同侧压力(0、0.06 f c、0.12 f c、0.18 f c、0.24 f c)的混凝土进行了静态(应变速率10-5/s)压缩试验,建立了基于Ottosen准则、Bresler-Pister准则以及Kupfer-Gerstle准则的混凝土冻融双轴受压破坏模型。通过分析发现,基于Ottosen准则、Bresler-Pister准则和Kupfer-Gerstle准则所建模型均能很好地反映侧压力在0~0.24 f c范围内的混凝土双轴受压破坏规律,基于改进Kupfer-Gerstle准则建立的混凝土冻融受压破坏模型计算精度更高,且适用于单轴和双轴受压破坏的模拟。展开更多
基金The Natural Science Foundation of Shandong Province(No.ZR2009FQ020)the Ph.D.Programs Foundation of Ministry of Education of China(No.20100131120042)
文摘In order to effectively assess the mechanical properties of concrete with freeze-thaw and seawater erosion, tests about basic mechanical properties of concrete after freeze-thaw and seawater erosion are conducted based on the large-scale static and dynamic stiffness servo test set. 50, 100, 200 and 300 cycles of freeze-thaw cycling are made on normal concrete, and the artificial seawater is produced. The reasonable wet and dry accelerate system is selected. 10, 20, 30, 40, 50 and 60 cycles of wet and dry cycling are made to concrete after freeze-thaw cycling. The degeneration law of the concrete elastic modulus and compressive strength is studied. The Ottosen tri-axial strength criterion considering cycles of freeze-thaw and wet and dry cycling is deduced based on uniaxial mechanical properties of concrete and damage theory. Experimental results show that with the increase in the number of wet and dry cycles and freeze-thaw cycles, the concrete axial compressive strength and the elastic modulus decline gradually. Tensile and compressive meridians of concrete shrink gradually. The research can be referenced for anti-crack design of actual structures eroded by seawater at cold regions.
文摘为研究不同冻融循环次数加载下混凝土的力学性能,利用大型多功能液压伺服三轴仪对双向应力状态下不同冻融次数(0、20、40次)和不同侧压力(0、0.06 f c、0.12 f c、0.18 f c、0.24 f c)的混凝土进行了静态(应变速率10-5/s)压缩试验,建立了基于Ottosen准则、Bresler-Pister准则以及Kupfer-Gerstle准则的混凝土冻融双轴受压破坏模型。通过分析发现,基于Ottosen准则、Bresler-Pister准则和Kupfer-Gerstle准则所建模型均能很好地反映侧压力在0~0.24 f c范围内的混凝土双轴受压破坏规律,基于改进Kupfer-Gerstle准则建立的混凝土冻融受压破坏模型计算精度更高,且适用于单轴和双轴受压破坏的模拟。
