Obayashi Corporation (Headquarters: Minato-ku, Tokyo, President: Kenji Hasuwa) has a concrete structure that uses a 3D printer-based outer shell manufacturing technology that uses cement-based materials and a robot that sprays or pours concrete. We have developed an automated construction system for objects. In addition, by applying this technology, we have succeeded in manufacturing precast concrete blocks (* 1) with Nippon Hume Co., Ltd. (Headquarters: Minato-ku, Tokyo, President: Minoru Okawachi).

In the past, manufacturing concrete structures required a lot of manpower, such as assembling and disassembling formwork and placing concrete. In addition, for large precast concrete products, steel formwork is custom-made, so the period from design to delivery is as long as about 10 months, and the manufacturing cost is high.

Therefore, Obayashi-gumi realized the automation of construction by printing the outer shell of precast concrete with a 3D printer using cement-based materials and spraying or pouring concrete with a robot arm that programmed the concrete placement route. .. This eliminates the need for manufacturing, assembling, and disassembling steel formwork, resulting in labor saving, process shortening, and cost reduction in formwork manufacturing in precast concrete manufacturing.

In addition, 3D printers can generate robot control information directly from blueprints, so it is possible to build structures that require complex formwork or a wide variety of formwork. We also confirmed that the outer shell printed by the 3D printer is integrated with the concrete and has the same strength as the precast concrete manufactured by the conventional method.

The features of this system are as follows.

Labor saving by automated construction

By printing the outer shell with a 3D printer, this system eliminates the need for assembling the formwork and disassembling after driving. In addition, the robot arm automatically performs concrete placing, which was done by several workers, and has realized labor saving up to one-third of the conventional one.

Shorten the manufacturing process of precast concrete

The outer shell made of 3D printer can be manufactured in a shorter period of time than the steel formwork, and since there is no waiting time until the formwork is diverted to the next production, the manufacturing process of precast concrete can be greatly shortened. Precast caisson foundation work, which requires the production of multiple precast blocks with custom steel formwork, can reduce the block manufacturing process from the conventional 10 months to 2 months.

In addition, since the robot arm automatically prints the outer shell and drives concrete, it is possible to manufacture 24 hours a day, further shortening the manufacturing process.

The outer shell made of 3D printer can be manufactured at a lower cost than the steel formwork even when compared including the cost of 3D printer and labor cost, and the formwork cost can be reduced by up to 50%.

Obayashi will continue research and development on the manufacture of concrete structures using 3D printers and robot arms, aiming to apply it to actual construction, and in the future, realize automated construction at construction sites.

(C) 2022 Electronic News Publishing, source ENP Newswire