摘要
利用大型静动真三轴试验机,进行了高强高性能混凝土在各种应力比下的多轴拉压试验,多轴拉压试件尺寸为100mm×100mm×100mm立方体。试件受压面的减摩垫层为三层塑料薄膜中间夹三层甘油;受拉面先用打摩机去掉表面层,然后用结构胶与加载板粘结。阐述了试件破坏形态特点以及观察了裂缝发展方向,测得了多轴强度与应变,剖析了应力状态和应力比对高强高性能混凝土多轴拉压强度与变形的影响规律性。试验结果表明:多轴拉压强度与变形变化规律取决于应力状态和应力比。多轴拉压强度σ1f、σ3f在所有应力比下分别小于其单轴拉压强度ft、fc;主拉峰值应变ε1p在单轴拉时最小,主压峰值应变ε3p在单轴压时最大。建立了高强高性能混凝土在多轴拉压应力状态下的破坏准则公式。
Multiaxial tensile-compressive tests were performed on 100mm×100mm×100mm cubic specimens of plain high-strength high-performace concrete （HSHPC） at variable stress ratios using a large static-dynamic true triaxial machine. Friction-reducing pads were composed of three layers of plastic membrane with glycerine in-between for the compressive loading plane; the tensile loading planes of concrete samples were processed by attrition machine, and then the samples were glued-up with the loading plate using structural glue. The failure characteristics of specimens and the crack directions were recorded and described respectively. The three principal strengths and strains in the corresponding stress state were measured. The influence of stress states and stress ratios on the triaxial strengths and peak strains of HSHPC was also analyzed respectively. The experimental results show that the changing of the multiaxial tensile-compressive strength and deformation depends on stress states and stress ratios. The multiaxial tensile-compressive strengths （σ1f ,σ3f ） of HSHPC at all stress ratios are less than the corresponding uniaxial tensile and compressive strength （ft, fc）. The tensile and compressive peak strains reach the least and greatest values under uniaxial tensile and compressive stress state respectively. The formula of a failure criterion under multiaxial tensile-compressive stress states for plain HSHPC was proposed.
出处
《工程力学》
EI
CSCD
北大核心
2010年第10期190-195,共6页
Engineering Mechanics
关键词
高强高性能混凝土
应力状态
应力比
多轴力学性能
破坏准则
high-strength high-performance concrete （HSHPC）
stress states
stress ratios
multiaxial mechanical behavior
failure criterion
