الفهرس 
Introduction
History of cable-stayed bridgesOnly 14 pages are availabe for public view
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Abstract
Bridges are the structures that connect parts of a city across the river or valley of any infrastructures that is dividing them and also they provide means of crossing natural and artificial obstacles in the environment. Both static and time domain analysis methods are presented. These methods are based on minimization of the total potential energy of the structural elements, using conjugate gradient technique. Cable-stayed bridges are the bridges that have one or more towers from which cables support the floor beam. Large amounts of compression forces are transferred from the deck to foundations through cables, then through pylons. The static analysis is carried out of three different types of bridges (Harp, Semi-Harp, and Fan) using all types of connection between floor beam and pylons. The models of five span cable stayed bridge having single plane of cables are considered. The bridges have two equal exterior spans of 140 m, each, and the interior spans are 280 m long each. The deck girder has a total span of 1120 m. The initial tension used for the analysis was 5%, 10%, 15%, and 20% of the breaking load of the cables, and then the initial tension obtained from cycle of solution technique was taken.The frequency domain analysis taking into consideration the initial tension of cables as the final tensions obtained from cycle of solution technique is carried out for all three types of bridge.The time domain analysis of the harp model is carried out for 90 seconds as a total time of analysis with time step of 0.02 seconds, so number of time steps was 4500. Damping ratio was assumed as 1.5%. For dynamic time domain analysis, the traffic load speed variation is taken into consideration, and the analysis is carried out under speed of 60 km/hr., 90 km/hr., 120 km/hr., and 300 km/hr., also the effect of some cable ruptures with the variation of the traffic load speed on the floor beam is studied. This thesis tracks in the following order, Chapter One:Contains an introduction for the thesis including the research objectives. Chapter Two:Covers the historical background of cable-stayed bridges and their structural components. Different characteristics of this type of bridges are presented. It includes a literature review of the previous work on the topic. Chapter Three:A method based on the minimization of the total potential energy for predicting static and dynamic response of the cable-stayed bridges is viewed. Chapter Four:Contains the static analysis for the three types of the cable-stayed bridges harp, semi-harp and fan with four different types of connection between floor beam and pylons. The analysis is carried out using a computer program based on the minimization of total potential energy by conjugate gradient technique. Chapter Five:The frequency domain analysis of cable-stayed bridges is carried out using SAP 2000. Chapter Six:The dynamic analysis of cable-stayed bridges using different moving loads speeds is carried out. Chapter Seven:Presents the static and dynamic analysis of cable-stayed bridges taking into consideration the effect of ruptures in some cables on the deflection and bending moment on both pylons and floor beam, and the variations of displacement, velocity and acceleration at the mid-joints of the floor beam. All results are tabulated and drawn. Chapter Eight:The summary and the general conclusions of the present work are included.