Tension members such as membranes and cables are lightweight and have a mechanical property that transmits only tensile force.Tension structure,for example,the membrane structure is constituted with those structural members,and often used as a structural system for a large spatial structure.The cable reinforced suspension membrane structure is targeted in this study.Generally,the structural rigidity as the membrane structure occurs by implementing the boundary condition and the initial tension into the tension member (membrane material) existing with no stress in the plane.Therefore,membrane structures require the form-finding analysis and the cutting pattern analysis unlike usual architectural structures[1].