高强钢纤维碳纳米管混凝土双轴受压试验与破坏准则

高强钢纤维碳纳米管混凝土(HSSFCNRC)是一种新型高强复合混凝土，具有流动性好、强度高、韧性大、耐久性好等显著优点。为探讨其多轴应力状态下的强度特征和变形特性，该文利用大连理工大学的大型静、动三轴电液伺服试验机，分别对普通高强混凝土(HSPC)和HSSFCNRC进行了不同应力比条件下的二轴受压对比试验，观察其破坏形态、得到了极限应力和峰值应变等其他参数。通过对Kupfer-Gerstle破坏准则、宋玉普模型和杨健辉模型进行的比较分析发现，HSPC和HSSFCNRC都适合这几种模型，但曲线包络线要优于折线包络线，且强度高的包络线包住强度低的，HSSFCNRC包络住HSPC。通过对八面体应力空间和应变空间的破坏准则分析发现，宋玉普模型的子午线为椭圆曲线，精确度较高；而文中采用的破坏准则子午线为直线，应用简便，也可满足工程应用要求。

Biaxial compression tests and failure criteria for high strength steel fiber and carbon nanotube reinforced concrete

High strength steel fiber and carbon nanotube reinforced concrete (HSSFCNRC) is a new type of high-strength composite concrete with good fluidity, high strength, toughness, durability and other significant advantages. In order to investigate the strength and deformation characteristics of HSSFCNRC under multi-axial stress states, a serial of biaxial compression tests with different stress ratios were conducted on high-strength plain concrete (HSPC) and HSSFCNRC, respectively. The failure modes of specimens were observed, the condition parameters, such as the ultimate stresses and the peak strains were obtained. By comparative analysis, Kupfer-Gerstle failure criterion, Song Yu-pu model and Yang Jian-hui model can all be used in HSPC and HSSFCNRC, but the envelope curves are superior to the envelope lines, and the envelope of HSSFCNRC can cover that of HSPC. The meridian of Song Yu-pu model is elliptic curve, and the precision is better. Although the simple meridian proposed in this paper is straight line, a conclusion is drawn that it can satisfy the requirements of  engineering applications by the comparative analysis of octahedral stress and strain space failure criteria.