摘要：This paper presents an optim.zation algorithm.for the design of tied back retaining wall which is com.rised of the sam. three basic elem.nts: stem. toe and heel, where the stem.is hinged to the base and tied to the heel by m.ltiple tie rods at intervals along the wall. The aim.of this study is to find the values of design variables for this suggested type of tied back retaining walls which m.nim.ze the cost function subjected to constraints of the problem. The optim.m.design of such structure is conducted by using one of the nontraditional optim.zation m.thods, genetic algorithm.(GA). The form.lation of the problem.is based on the elastic analysis and the ultim.te strength m.thod of design as per ACI-318-2011 code. The built-in genetic algorithm.optim.ool of m.tlab program.is utilized to optim.ze the cost function of the wall. The cost of concrete, reinforcing steel, tie steel, form.ork, excavation, and backfilling works are included. The considered design variables are the geom.tric dim.nsions and the am.unts of reinforcem.nt for the base slab and stem.slab, as well as the am.unt of tie steel. The developed program.is utilized to perform.an extensive param.tric study regarding the height of wall, backfill soil properties, and m.terials properties including concrete, reinforcing steel, and tie steel. The backfill properties are represented by a pressure coefficient, which is a function of the unit weight and the angle of internal friction. Average expressions are calculated for the total cost and optim.m.dim.nsions as ratios of the wall height H2 which m.y be useful for the practical design of walls.