Publish: 25 Jul 2020, 01:36 pm
According to a report on the Nikkei Asian Review website, Obayashi Corporation, one of Japan's five largest construction companies, is constructing a dam almost exclusively with machines, tackling the industry's labor shortage and ageing workforce.
The dam project is located in Mie Prefecture, in the south-east corner of the main island of Japan, reports UNB.
The 84-meter-high structure is scheduled to be completed in March 2023.
During its construction, Obayashi will test a number of robotic and automation technologies.
Obayashi also built automatic machinery to stack concrete layers into a dam.
To order to further streamline the operation, a plant was constructed near the site to combine sand and gravel with cement to produce concrete.
Building a dam requires knowledge and skill that has been developed through years of experience. Obayashi 's automated system is expected to be a game-changer in the construction of the dam as well as in other applications.
"By transferring expert techniques to machines, we're able to analyze what was once implicit knowledge," said Akira Naito, head of Obayashi's dam technology unit.
Each process for constructing a 334-metre-wide dam will involve some form of automation. This includes the initial work of establishing the foundation and putting the body into concrete form.
The dam body is constructed in layers by pouring concrete into 15-metre-square-metre partitions. Tower cranes pouring concrete are remotely operated by office machines, which often track the orientation of the partitions and the speed of the construction phase.
Humans will man the cranes for safety reasons, but the machines are self-operating.
Building a dam is an intricate endeavor that requires all crevices to be sealed to prevent breaches. Concrete surfaces need to be processed so they are tightly stacked on one another.
Layers that are uneven are generally rubbed down by human experts until they are smooth. Obayashi has created devices that manage the brushing process. The duration of cyclic brushing and surface pressure is regulated automatically.
As poured concrete builds up, the forms used to give it structure need to be raised to keep unset concrete from leaking out. Normally, multiple skilled workers in heavy machinery operate in tandem to gradually lift the forms, calling out to each other to coordinate their movements.
Obayashi has developed a robot to handle this task, allowing for humans to be cut out of the picture entirely.
Surprisingly, Obayashi says all of its futuristic solutions have only increased productivity by about 10%, since it still needs to have people on-site ready to jump in should things go wrong. The company plans to acquire more know-how so it can eventually reduce the amount of manpower it needs.
"Eventually, we may be able to cut building time by 30%," said Naito.
Other Japanese contractors are also working on automation. Kajima has developed self-driving bulldozers and dump trucks so construction can continue 24 hours a day. It has automated the lifting of concrete forms, which it used at a dam construction site in Hokkaido for the first time.
Dam construction is particularly conducive to automation since it involves a lot of repetition and tends to occur at sites far from population centers, which means that there is less risk of automated equipment hitting bystanders or other machines.
Japan's construction industry is aging quickly, with 35% of all workers now 55 or older, according to the Japan Federation of Construction Contractors. Companies are scrambling to build robots based on workers' expertise before they retire. The companies also hope that new technology could dispel negative stereotypes of the industry among younger generations, encouraging more people to work in construction.