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CTS - Cable tensioning strategy

During construction of structures with post-tension cables or cable-stayed structures, the purpose is the achievement of the "design" stress for each cable. For instance if we consider a cable stayed bridge with 10 cables we need to apply a certain stress to the cables in order to achieve a certain geometric configuration of the bridge (for example one typical target is the achievement of the "zero" displacement condition of the deck under permanent loads). Then each cable needs to be install and then needs to be put in tension (design tension). The achievement of the design tension is an iterative process because a variation of tension in each cable means a variation in tension (plus, minus or zero) for the other cables.    

 
 

In addition to all above mentioned is not less relevant that when there is a certain variation of tension in the cable means variation in geometric configuration that could end up with a not  acceptable rotation or not acceptable displacements of  specific points of the structure (control points). 

 
 

For those reasons has been studied an analytic and computational method that provides the sequence of the tensioning procedure (for each stage is shown the number of cable that needs to be put in tension and the value of tension [KN]). In accordance with minimizing the number of operations and maintain the structure inside a certain allowable domain.