The Production of a Topology-Optimized 3D-Printed Concrete Bridge

Abstract

In the last few years, the development of 3D concrete printing (3DCP) technology has flourished exponentially both in academics and the construction industry. Many problems inherent to 3DCP are already being tackled on a material level. However, in the practical realization of large-scale components there are still a lot of questions to be answered. In this study, we discuss the production process of a topology-optimized 3D-printed concrete bridge structure. As the entire process is largely different compared to the manufacturing of traditional concrete structures, the problems, workarounds, and insights gathered from this project are valuable for future constructions using 3DCP. The geometry of the bridge was based on topology optimization results and further developed through the use of parametric modelling. After careful considerations, the bridge geometry was discretized into four segments and printed as integrated formwork. Several measures were taken during the printing process in order to produce the separate sections. The assembly process entailed the handling of the printed components, the placement of reinforcement and prestressing tendons, the production of the end blocks, and the handling and joining of the printed sections. For the latter, also the process of pouring self-compacting concrete in the printed formwork is discussed and more details about the post-tensioning procedure are provided.

A comprehensive review of sustainable materials and toolpath optimization in 3D concrete printing

“…By harnessing the inherent freedom of design, 3DCP can create structures that are aesthetically appealing and optimized for performance and functionality 87 . For instance, the optimization of material distribution in 3DCP is a vital research direction to minimize material waste and optimize structural efficiency 14,96 . Since the last decade, structural topology optimization has been increasingly applied in 3DCP 97,98 .…”

“…These include using additive manufacturing techniques to build complex geometries and incorporating reinforcement elements during the printing process 14,86,99 . Existing works 96,97 have demonstrated the ability to optimize the internal structure of concrete components, resulting in improved mechanical properties and enhanced performance.…”

“…Instead, they synergistically collaborate with tensioned steel cables to create an effective composite structural system. The previous study 96 examined the production process of a topology-optimized 3D printed concrete bridge structure, highlighting its significant deviation from the manufacturing procedures of conventional concrete structures. Yang et al 103 presented an integrated design method for 3DCP by incorporating extrusion-based manufacturing characteristics into the topology optimization algorithm.…”

“…In recent years, there have been key research developments 14,15,96,119 in toolpath design and optimization. One of the key areas of focus has been on optimizing toolpaths for material efficiency and print time reduction.…”

3D Printing Technology for Rapid Response to Climate Change: Challenges and Emergency Needs

“…Both approaches start with formwork 3DP; then, the concrete is cast using extrusion-based technology. The emergence of 3D concrete printing for emergency infrastructure needs epitomizes a burgeoning field of technological innovation [25]. The pioneering Striatus bridge in Venice and the world's first 3D-printed reinforced, prestressed concrete bridge in the Netherlands epitomize the immense potential of 3D concrete printing.…”