With the rapid development of China's economy,the country has put forward higher requirements for energy conservation,emission reduction,and low-carbon environmental protection.Engineering experience has shown that the slenderness ratio has a significant impact on the load-bearing performance of slender load-bearing components.For the purpose of economy and energy conservation,concepts such as the ultimate pull-out force per unit volume and the optimal slenderness ratio were proposed.A calculation and analysis model for the fully grouted anchorage system was established using PFC software.The influence of slenderness ratio on the pull-out performance of the fully grouted anchorage system was systematically studied from the changes in anchorage length and anchorage width dimensions.Research has shown that:(ⅰ)The slenderness ratio directly affects the pull-out performance of the fully grouted anchorage system;(ⅱ)For a fully grouted anchorage system under specific conditions,there exists an optimal slenderness ratio that can achieve the goal of using the least amount of material to maximize bearing capacity;(ⅲ)The research conclusion on the influence of slenderness ratio on the pull-out performance of the fully grouted anchorage system under two-dimensional models is also applicable to three-dimensional models or real working conditions.