Architects and civil engineers are continuously looking for new and efficient methods to coverrnlarge spaces using the least materials and minimum number of columns. Thin concreterncylindrical shells can cover the roofs of various buildings efficiently and aesthetically.rnCommon theories adopted for analysis of cylindrical shells interpret the design behavior inrndifferent ways. Nowadays it is easy to study shells to a desired level as tedious handrncalculations are minimized due to the appearance of computer. As a result their behavior,rnspecially their structural behavior, can be studied and designed by varying various parametersrnof the shell.rnThe parameters, which are studied in this paper, are named as length, radius and thickness ofrnthe shell. Many researchers use computer knowledge to study shell behavior under variablernparameters. This research was do ne using commercially available software MATLAB,rnExcel and manuals. Appropriate shell geometry, loading condition, material as well as otherrnnecessary parameters were assumed and selected according to manuals, codes and standardsrnto achieve accuracy. The analysis was performed for stiffened and unstiffened single andrnmultiple spans of reinforced concrete cylindrical shells with varying shell thickness, length,rnand radius keeping other things constant. Three models and seven trials with variablernparameters for both single and multiple spans have been analyzed under dead and live load tornobtain variable force, moment, stress and displacements.rnResults obtained from this research indicated that shells are varied in their behavior as one orrntwo parameters changed as shown from Table (8-16) and Figure (5-7). Forces, moments,rnstresses and displacements were increased under increasing length and radius of shell.rnHowever, stresses and displacements were decreased and forces and moments were increasedrnwith increasing thickness of the shell. This study also adhere the reduction of internal effectsrnwhen st iffeners were introduced and increasing depth edge beam were reduced the forces,rnmoments, stresses and displacements. Finally it was also plotted a graph along longitudinalrnand circumferential directions of the shell for the purpose of reinforcement detailing.