Bridges Post-Tension Superstructures

ABSTRACT
Bridge projects come at the top of the vital national projects to which countries pay special attention and which require precise designs and correct implementation. The research paper presents one of the design methodologies for bridge superstructure as it achieves design safety and economic requirements and the associated duration and quality of implementation. Adopting the idea that the design of pre-stressed and pre-cast concrete systems in particular...
It leads to distinguished results in this regard, and some sketches and calculations of actual cases that have been applied have been included.
In the field of civil engineering, pre stressed concrete structures are mainly considered one of the more recent types of constructions. The first successful applications of pre stressed concrete were done in the early 20th century and are attributed to the French engineer Eugène Freyssinet. He succeeded in replacing low-strength steel by using high-strength steel. For more than a century, pre stressed concrete structures have become a main common part of civil engineering since this type of construction material has multi applications in bridges engineering . According to records and measurements, more than 45% of bridges built in the United States since 2010 have been designed as pre stressed concrete structures .Recently , new materials such as ultra-high-performance concrete (UHPC) can improve the mechanical properties of these structures . The advantages of pre stressed concrete get from the essence of preloading of structures by compressive force.