Introduction.- Optimum Design of Castellated Beams Using Tug of War Algorithm.- Optimum Design of Multi-Span Composite Box Girder Bridges Using Cuckoo Search Algorithm.- Sizing Optimization of Skeletal Structures Using Enhanced Whale Optimization Algorithm.- Size and Geometry Optimization of Double Layer Grids Using Colliding Body Optimization (CBO) and Enhanced Colliding Body Optimization (ECBO) Algorithms.- Sizing and Geometry Optimization of Different Mechanical System of Domes via ECBO Algorithm.- Optimal Design of Double Layer Barrel Vaults Using CBO and ECBO Algorithms.- Optimum Design of Steel Floor System Using ECBO.- Optimal design of the monopole structures using CBO and ECBO algorithms.- Damage Detection in Skeletal Structures Based on Charged System Search Optimization Using Incomplete Modal Data.- Enhanced Colliding Bodies Optimization for Modification of Ground Motions.- Bandwidth, Profile and Wavefront Optimization Using PSO, CBO, ECBO and TWO Algorithms.- Optimal Analysis and Design of Large-Scale Domes with Frequency Constraints.- Cost and CO2 Emission Optimization of Reinforced Concrete Frames Using ECBO Algorithm.- Construction Site Layout Planning Problem Using CBO and ECBO.