الفهرس 
Chapter (1) IntroductionOnly 14 pages are availabe for public view
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Abstract
? The main aim of the present work is to investigate both the static and dynamic analysis of circular cable suspended roofs taking into account the nonlinearity of these systems. The classification, pretensioning, protection, mechanical properties and the static analysis of freely hanging cable under uniformly distributed load are given. Classifications, main elements, materials, advantages and disadvantages of cable suspension roofs are included. Static and dynamic loads which affect cable roofs are presented with special care for wind because of its importance for cable roofs. Methods of analysis of cable suspended roofs are presented with a brief review for the previous works in this field. Method of minimizing the total potential energy (TPE) using the conjugate gradient (CG) technique to predict the static response of cable roofs is introduced. Time domain analysis by expanding the method of minimizing total potential energy to include dynamic loads and responses is completely presented. Also, the method of the frequency domain analysis is given. An approach to evaluate the dynamic response due to wind is included. Many circular cable roofs have been analyzed using a computer program based upon the minimization of (TPE) by the (CG) technique. The results of the analysis were used to investigate the factors that affect the design and the response of cable nets which include the span, the spacing between nodes, the uniformly distributed applying load, the steel area of the cables, the modulus of elasticity, the pretension in cables, the required nodal deflections, the maximum allowable final forces in cables, and finally, the sag / span ratio. A complete description of the deflections and the forces, produced in a circular cable net with the diametrical member divided into ten segments, is presented in nondimensional table and graphs. These nondimensional table and graphs kink between the previous factors that affect the design and the response such a structure. New relationships between the forces and the deflections in two cable nets with different numbers of segments in their diametrical members were reached. These relationships are used to invert any cable net to an equivalent cable net with ten segments in the diametrical member and this cable net can be preliminary designed using the previous nondimensional table and graphs. Generally, these tables, graphs and relationships form a good technique for the preliminary design of circular cable suspended roofs either nets or grids. This good preliminary technique was examined using several examples and the results are in good agreement with these solved using the computer program based on minimizing the (TPE) using the (CG) technique for the analysis of cable nets. Finally, computer programs for the dynamic analysis were used to investigate the factors that affect the frequencies of circular cable suspended roofs and to express their dynamic behavior.