[ Three-dimensional printing brings innovation to manufacturing technology ©GettyImagesKorea ]

In general, printing refers to reproducing words or images with the use of a machine. The concept of 3D printing is greatly different from that of existing printing, in that 3D printing produces three-dimensional structures through a nozzle, not on a plane. In this regard, 3D printing is called “innovation of manufacturing technology” in the Fourth Industrial Innovation era. The novel printing method is designed to generate three-dimensional outputs in a way to pile up materials, instead of cutting-off. The recent development of related technologies has made it possible to produce various and sophisticated products ranging from daily supplies to medical and machine parts by using 3D printers.

[ Stacking of materials based on 3D printing technology can lead to building wall structures ©GettyImagesKorea ]

The development of 3D printing technology has an impact on the construction industry. Instead of ink, 3D printers use various materials such as plastics and metals to build three-dimensional structures. Recent technological development has led to a more extensive use of materials. The construction industry has also expanded possibilities to use 3D printing technology by utilizing materials including concrete, cement and plaster mainly used to build structures. Moreover, size limitations for structures could be overcome through the industry’s attempts to hang a nozzle in the air or enlarge the printer size.

Hyundai E&C, which already identified possibilities for 3D printing, has been taking quick actions to develop future technologies. As some buildings with irregular forms are often considered landmarks in their regions and countries, more importance is being given to the construction technologies aimed to build irregular façades. Against the backdrop, the builder was promoted to utilize 3D printers to realize structures in a more freely and accurate way.

[ Forms shaped through irregular molds generated using 3D printing technology ]

To gain the upper hand in irregular-shaped construction, Hyundai E&C is accelerating its efforts to conduct research on 3D printing and develop the related technology to manufacture irregular molds, in cooperation with 3D Factory which has focused on the development of large-scale 3D printing since 2019. The use of the existing mold materials, including plywood and steel, requires higher costs and longer periods to produce irregular forms with more precision. On the other hand, 3D printing mold forms can be made with a wide range of materials such as general plastic, high-strength carbon fiber and glass fiver. The mixture of such materials can lead to generating new types of materials with optimal strength and elasticity, enabling the realization of various forms with complicated curves.

In addition, a large-scale 3D printer can produce a mold, 2.5 meters in width, five meters in length and 1.5 meters in height, at a time. This printing technology can lead to precise manufacturing by keeping the machining error within 0.001 millimeters. It also can reduce the manufacturing period and increase the quality of outcomes.

[ (above) Irregular fillers produced through 3D printing / (below) Steel mold for TBM segments made through the assembly of irregular fillers ]

Hyundai E&C is conducting research on the manufacturing of molds designed to produce TBM segments through 3D printing technology. The precast segments form the inner wall of a tunnel excavated with the TBM (Tunnel Boring Machine). In the past, steel mold forms were needed for each segment shape. However, the use of 3D printing can produce irregular fillers of various shapes depending on purposes, which leads to replacing and installing them in an easier way. It is possible to effectively manufacture curve-shaped segments of different shapes by using only one mold form. This is expected to increase quality and reduce manufacturing costs.

The 3D printing mold manufacturing is in the stage of technological development. Hyundai E&C will test the availability of irregular small structures in 2021. After verifying the technology, Hyundai E&C is planning to test-operate it in construction sites.

[ Outdoor bench manufactured through 3D printing ]

It is not difficult to find the examples of the utilization of 3D printing technology in everyday lives. Hyundai E&C’s Hillstate Lake Songdo II displays an extraordinary structure made through 3D printing. This outdoor bench, one meter in width, one meter in height and eight meters in length, was manufactured by assembling and processing about 200 members of framework in different forms based on 3D printing technology.

Three-dimensional printing is considered a core technology in the Fourth Industrial Revolution era and one of the most innovative technologies which will change the future. Much hope is pinned on the development of new construction technologies related to 3D printing, whose scope of application is expected to expand in the construction industry.