变速率加载下有侧压混凝土强度和变形特性

Strength and deformation characteristics of concrete subjected to different loading rates combined with confined stress

利用大连理工大学海岸和近海工程国家重点实验室最新研制和改造的大型混凝土静、动三轴试验系统 ,进行了 6 4块普通混凝土试块在 4种常定侧应力等级和 4个数量级加载速率的混凝土双轴压试验 .系统地探讨了有侧应力作用时 ,混凝土在不同加载速率下的受压变形和强度特性 .在此基础上 ,建立了以应变和八面体应力空间表示的有恒定侧压混凝土在不同加载速率下的破坏准则 ,为地震区的混凝土结构、海上混凝土采油平台和核防御壳等结构受动态双轴压组合荷载作用的分析奠定了可靠的基础 .

More than sixty blocks of concrete compressive tests were completed under four kinds of lateral stress classes and four orders of loading rate conditions with the galleon concrete static and dynamic test system which was rebuilt recently in the State Key Laboratory of Coast and Offshore Engineering, Dalian University of Technology. The compressive deformation and strength of the concrete under different loading rates and lateral stresses are studied systematically in the paper. The mathematical formula of concrete failure criterion which is described with octahedron stress space or deformation is established based on the experimental data.The study results have laid a reliable foundation for the dynamic analyses of concrete structures, such as structures within the earthquake regions, concrete oil plateforms, defence shucks which are subjected to different loading rates combined with a constant lateral compressive stress.