en Optimal design Optimal design پژوهشي Research <span style="font-size:11.5pt"><span style="text-justify:inter-ideograph"><span style="text-autospace:none"><span new="" roman="" style="font-family:" times=""><span style="color:black">The primary objective of this paper is to propose a novel technique for hybridizing various metaheuristic algorithms to optimize the size of discrete structures. To accomplish this goal, two well-known metaheuristic algorithms, particle swarm optimization (PSO) and enhanced colliding bodies optimization (ECBO) are hybridized to propose a new algorithm called hybrid PSO-ECBO (HPE) algorithm. The performance of the new HPE algorithm is investigated in solving the challenging structural optimization problems of discrete steel trusses and an improvement in results has been achieved. The numerical results demonstrate the superiority of the proposed HPE algorithm over the original versions of PSO, ECBO, and some other algorithms in the literature.</span></span></span></span></span><br> &nbsp; Structural optimization, metaheuristic, particle swarm optimization, colliding body optimization, truss structures. 1 15 http://ijoce.iust.ac.ir/browse.php?a_code=A-10-66-391&slc_lang=en&sid=1 A. Yadbayza-Moghaddam 180031947532846002474 180031947532846002474 No Department of Civil Engineering, Urmia University, Urmia, Iran S. Gholizadeh s.gholizadeh@urmia.ac.ir 180031947532846002475 180031947532846002475 Yes Department of Civil Engineering, Urmia University, Urmia, Iran