Abstract:Evaluation of the effects of slope reinforcement is one of the key factors in slope reinforcement. Evaluation methods can be broadly classified into two categories. The first category is the analysis of engineering geological conditions and qualitative research or semi-stable method on rock mechanical,which is short of accuracy. The second category is the quantitative evaluation method based on the analysis of field monitoring,which is insufficient because the judgment based on the monitoring data cannot be obtained unless the measuring point is installed and monitored. Degree of reinforce demand(DRD) is a new evaluation method with unique advantage,which combines the two methods mentioned above in order to make best use of their advantages and bypass the disadvantages. The 435 m-high excavated slope of Longtan Hydropower Station in Guangxi threatens the security of the dam,whose deformation and stability are of great importance to the power station. To demonstrate the DRD evaluation,an application in zone A on the left bank of the hydropower station is described. The evaluation results indicate that the reinforcement of the slope is fairly effective,which agrees well with the monitoring data and the field investigation results.