Abstract: Anchor bolt support is commonly used in slope reinforcement. Analysis on the causes of anchor’s axial force is of vital significance as the assessment of reinforcement effect is often dependent on the anchor’s axial force which is influenced by many factors. In this article, a multiple linear regression model of anchor’s axial force was established for a ultra-high rock slope of an expressway. Firstly, factors affecting the axial force were analyzed in qualitative terms, and then the factors were quantified. Furthermore, the real axial force was calculated in no consideration of temperature influence. The aim is to accurately assess the anchorage effect and reduce misjudgment of slope deformation. The model was applied to the calculation of real axial force at point MGZ1042 of the anchor bolt. In the absence of the influence of temperature, the axial force fell from 100kN to 40kN, not exceeding the monitoring alarm value 60 kN.

Key words: rock slope, axial force of anchor, monitoring, temperature influence, regression model