Abstract: Force density method is frequently used for form-finding of tensioned membrane structure．In this paper the use of “T-element” in force density method is discussed‚meanwhile‚direction of cable net and the effect of prestress of fixed cable in “T-element” on braced structure are also studied．In addition‚force density method is perfected in this paper．

Key words: tensioned membrane structure, force density method, direction of link gird, T-element