Abstract
The construction of pre-stressed concrete structures requires the use of specialized equipment and techniques. Prefabricated panels and/or beams are used to quickly assemble and dismiss a wide range of recognizable structures, such as walls and bridges. This paper reviews the advantages of pre-stressed concrete and examines the methods on how to construct such structures. In part, it further outlines the considerations of safety, labor requirements and time frame, as well as environmental impact associated with prefabricated prefabrication.
Introduction
The field of structural engineering is ever changing and one of the leading innovations has been in the use of pre-stressed concrete. Pre-stressing concrete is the application of stresses before loading in order to reduce the magnitude of stresses under service loading. This form of structural engineering approach enables efficient usage of materials as well as increasing structural resistance to varying degrees of loading. Pre-stressed concrete structures are typically faster to erect than traditional rigid frame structures due to the use of specialized tools and techniques, most of which are easily accessible in modern construction.
Advantages of Pre-Stressing Concrete Structures
Pre-stressing concrete structures present a number of advantages such as improved construction speed, economic savings, and enhanced structural performance. Firstly, pre-stressing concrete structures can be built faster than traditional rigid frame structures due to prefabrication and accelerated formwork, the use of reusable formliners, and pre assembly of components. Additionally, reduced construction duration means that there is lower dependence on external labor which equates to economic savings on labor costs. Pre-stressing concrete also allows for improved structural performance in terms of bearing capacity, ductility, longevity, and aesthetics.
Methods of Pre-Stressing Concrete Structures
The pre-stressing of concrete typically entails the installation of strands or strands of high tensile steel wire or bars, referred to as tendon, that are placed in confined spaces throughout the structure and prestressed to an designed strain limit via a post-tensioning system. Tendon can be grouped in different arrangements such as single, double, or triple and can follow different layouts, e.g. fan, continuous, zig zag, in order to dissipate tension throughout the space.
Construction Considerations
Constructing pre-stressed concrete structures requires careful consideration and attention to safety. Prefabricated components vary in weight and require rigorous handling using specialized equipment that is operated by qualified personnel. Quality control of the pre-stressing procedure is also necessary in order to ensure that the anticipated deflection and strain in the pre-stressing units are achieved. Additionally, it is essential to consider the environment in which the construction will take place, how it might be affected, and how to mitigate negative impacts.
Conclusion
Pre-stressed concrete structures offer a range of advantages when compared to traditional rigid frame construction. They are faster to erect and require lower labor inputs. Prefabrication also leads to improved structural performance in terms of bearing capacity, ductility, longevity, and aesthetics. However, pre-stressed concrete construction requires careful consideration in terms of safety, labor requirements and time frame, as well as environmental impact.
