Which of the following prefabrication techniques is used in bridge construction?

Explanation:

Precast Segmental Construction

• Precast segmental construction is a widely used prefabrication technique in bridge construction. In this method, segments of the bridge—typically portions of the superstructure like girders or deck sections—are cast in a controlled factory environment and then transported to the construction site. These segments are assembled either by placing them on falsework or by using launching girders or cranes. This technique offers numerous advantages such as improved quality control, faster construction times, reduced site work, and minimal disruption to traffic. It is particularly effective for long-span and urban bridges, including segmental box girder bridges. Due to its widespread application and proven efficiency in bridge construction, this is the correct answer.

Additional InformationPanelised Construction

• Panelised construction involves producing flat building elements, such as walls, floors, or roof panels, in a factory setting. These panels are then transported to the construction site and assembled. This method is widely used in residential and commercial building projects due to its speed and quality control. However, panelised construction is not typically suitable for bridge structures, which require large and heavy structural elements that need to withstand significant loads and dynamic forces. Hence, this technique is rarely used in bridge construction.

Formwork-Free Construction

• Formwork-free construction involves techniques that do not rely on conventional formwork systems for shaping concrete. Examples include slip-forming, where concrete is continuously poured into a moving form, and 3D concrete printing, which builds structures layer by layer. While innovative, these methods are still in developmental or niche use cases and are not commonly adopted in large-scale bridge projects. Their application in bridge construction is limited and experimental at present.

Modular Construction

• Modular construction involves creating large modules or units of a structure off-site and transporting them to the site for installation. This method is popular in building construction due to its speed and reduced site disruption. While it has potential in bridge construction—such as for pre-assembled abutments or short pedestrian bridges—it is not the primary or most commonly used technique for standard bridge structures. Its use in bridges remains limited compared to precast segmental methods.