In the system of uniaxial loading with servo control, a loading test on the rock-like samples was carried out Based on the deep analysis of the experimental progress and phenomenon combining numerical analysis results, the fracture failure mechanism of rock-like materials with a horizontal fissure under single-pressure was explored. For the description of fracture morphology, the concept of relative open degree fi was introduced, and it is defined as the ratio of fracture apertures and fracture length. The results show that /?=0.005 can be set as the cut-off point. There are two different kinds of failure models, I.e., Crack central tension failure and crack tip yield failure. When fi is smaller, the stress intensity distribution in the neighborhood of crack tips can be obtained based on the analytical solution formula of the progressive stress near the crack tip. While fi is bigger, the failure of cracked sample starts from the appearance of micro-crack, which is made by the transverse tensile in the middle of the horizontal crack. In this case, the distribution theory of the progressive stress near the crack tip is not applicable.%在伺服控制单轴加载系统下对含有1条水平裂隙的类岩石试件进行加载试验,在对实验过程及现象深入分析的基础上,结合数值分析结果,探索单压条件下含有1条水平裂隙的类岩石材料断裂破坏机制.为描述裂隙形态,引入相对张开度β,并规定其为裂隙张开度与裂隙长度的比值.结果表明:以β=0.005为分界点,根据β的变化,裂隙体呈现出裂隙尖端屈服破坏和裂隙中部受拉破坏2种不同的破坏模式；当β较小时,水平裂隙尖端邻域应力分布状态可以根据裂纹尖端附近渐进应力解析解折减后计算；当β较大时,水平裂隙中部材料受横向拉伸时微裂纹出现,此时裂纹尖端附近渐进应力分布理论不再适用.
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