A study on the effects of blast loads on tower-line coupling, single tower structure andrntower-line structure system has been conducted and a variety of structural responsernvariables have been compared. Time history analysis has been carried out by consideringrndifferent charge blast parameters and stand-off distances. Various combinations of chargernweights and stand-off distances have been considered both on coupled- and uncoupledrntower arrangements along with detailed study of the effects of conductor coupling duringrnthe analysis modeling and subsequent design of transmission towers. rnThe modular and powerful finite element analysis software Dlubal-RFEM has beenrnutilized for the blast-oriented linear implicit dynamic analysis of latticed transmission linernstructures covered in this study. The transient dynamic equilibrium equations of the towerrnhave been directly solved by Newmark time integration method. The various internalrnforces, displacements and a variety of dynamic response behaviors have been isolated,rnrecorded and compared for a single tower and tower-line coupled systems under differentrncharge weight and stand-off scenarios. When numerically modeling and analyzing thernstructure, both coupled and uncoupled tower-line arrangements, three-dimensional naturalrnvibration analysis has been taken into account. rnFindings from numerical experiences on several analysis models have indicated that therntower-line coupling system significantly influences the response of tower structures withrnparticular significance on tower supports. Current design codes and guidelines have few,rnif any, methods or recommendations to deal with power transmission towers subjectedrnto blast loads and, when they do exist, they do not comprehend corresponding tower-linerncoupled effects. The study has indicated that internal forces in members of uncoupledrntowers are generally larger than the corresponding values in coupled systems. The mainrndifference arises in the support reactions. Several study models from this work havernindicated that there is up to nearly four-fold increase in support forces in uncoupledrnsystems which subsequently greatly influence the planning, selection, design and detailingrnof support systems for such structures. Thus, the study has revealed the fact thatrnestablishing support forces by considering a single uncoupled tower will lead tornunderestimating critical loads. When designing such structures, coupling effects should bernincorporated in the analysis process.