Abstarct: In this thesis special truss moment frxame behavior co-efficiency with two patterns of truss members in the form of vierendeel and x-diagonal through using the Yang method was determined by baxsed on the convergence method. baxsed on the results of this thesis, truss moment frxames with the form of vierendeel have a better ductility than the X form. Also, with the increase of the number of frxame span and the number of floors ductility increases. baxsed on the obtained results from 3 to 5 floors R in the area 3.94<R<6.35 and 6 to 8 floors in the area of 7.77<R<12.53 is obtained. Later the analysis of vierendeel truss baxsed on different ratio of special segment span to the height of truss to obtain suitable behavioral co-efficiency is done. baxsed on the obtained results with increase of the mentioned ratio behavioral co-efficiency increases.