GIKEN LTD. sends prayers and best wishes to everyone affected by the road collapse in Yashio-shi and condolences to the family and other associates of the driver who regretfully lost his life.
GIKEN LTD. (Head Office: Kochi-shi, Kochi; President and CEO: Atsushi Ohira) and group company GIKEN SEKO CO., LTD. (Head Office: Kochi-shi, Kochi; President and CEO: Akihiro Nishigawa) are using the unique press-in method of GIKEN to work towards fast recovery of the collapsed road and sewers at the site of the road collapse in Yashio-shi, Saitama.
Near the end of January this year, there was a major road collapse at the site. A truck fell into the sinkhole, with uncertainty over the safety of the driver. The rescue efforts were made extremely difficult by the flowing sewerage and debris as well as the successive collapse of the ground. Many units of SILENT PILER™, the hydraulic pile press-in and extraction machine of GIKEN, were used for the urgent work of building a sewer bypass route and establishing a rescue shaft as well as creating an entry route to the damaged area of the sewer pipe. GIKEN LTD. and GIKEN SEKO CO. LTD. cooperated with on-site users and contributing to the rescue efforts. As part of these efforts, in February, GIKEN SEKO started by using SMART PILER™ to press in 500 steel sheet piles in three days for soil stabilisation, which was necessary for the rescue shaft. In March, GYRO PILER™ was brought in for the excavation work to secure an entry route and used to build a continuous retaining wall using tubular piles.
Currently, recovery work for the sewer pipe is still on-going, and the two companies will further deepen collaboration with the relevant agencies towards recovery so that residents can live safely and with peace of mind as soon as possible.
Similar to this case at Yashio-shi, sewer pipes laid across Japan are showing signs of aging, with the risk of road collapse existing at various locations. Therefore, the national government is systematically inspecting and reinstalling sewer pipes. The GIKEN Group will use the experience this time to strengthen technological proposals to the national and local governments as well as work on developing new technologies to protect the lifelines essential for residents' livelihoods into the future and contribute towards developing safe and secure urban areas.
Sewer pipe recovery work underway since May
■ Overview of Work
A temporary drainage pipe that serves as a bypass around the damaged area was installed underground. At the same time, a shaft to rescue the driver, who was trapped inside the sewer pipe, was constructed, and excavation work for approaching the driver from the damaged area was also carried out.
* Image source: "Road collapse accident caused by sewer pipe in Nakagawa River Basin" (Saitama Prefecture's website)
（ https://www.pref.saitama.lg.jp/c1502/news/nakagawa0128.html?from=chumoku#kusakukoji ）
■ Overview of Construction by the GIKEN Group
In late February, as a measure against muddy water arising from soil stabilisation for installation of a shaft, group company GIKEN SEKO used SMART PILER™, which achieves faster work with a lighter equipment weight, to work around the clock and complete the press-in of 500 steel sheet piles in three days. Similarly, GYRO PILER™, a rotary cutting press-in machine for tubular piles, was introduced in mid-March to build a retaining wall for the establishment of an entry route from the damaged area towards rescuing the trapped driver. Over a period of 22 days, 30 tubular piles were pressed in, ensuring safety of the excavation work. Since May, the press-in of 26 tubular piles has been completed towards recovery work for the sewer pipe.
■ Reason for the Adoption of the Press-in Method
The situation at the site was extremely difficult, requiring maximum consideration for the surrounding residents as well as having limited space for work. The press-in method of GIKEN allows piles to be installed without vibration or noise. Furthermore, the construction machines are lightweight and compact, and can move on top of the installed piles, allowing space-saving construction. There is also no risk of falling over and such because the machines always grip firmly onto the top of installed piles. Recognition for the technologies of GIKEN came from being capable of quickly and safely carrying out several types of construction in parallel within a limited work area where various heavy machines are busily working around the clock.
■Actively Proposing Measures for the Aging of Sewer Pipes, Which Is Becoming a Social Issue
Due to the road collapse in Yashio-shi, the Ministry of Land, Infrastructure, Transport and Tourism has asked all local governments to carry out emergency inspections of sewer pipes installed in 1994 or earlier with a diameter of 2 m or more. The total length of such pipes amounts to approximately 5,000 km. In addition, many sewer pipes run below roads, and it is therefore necessary to limit impact—such as on traffic and the living environment—as much as possible when carrying out repairs.
GIKEN will continue to actively propose the most appropriate methods using press-in technologies to local governments. At the same time, GIKEN will also develop the most appropriate technologies in response to the situations at construction sites.
■Profile of GIKEN Group
GIKEN developed the SILENT PILER™, the world’s first reaction-based, non-vibratory hydraulic pile driving machine that operates with minimal noise impacts. The GIKEN Group now actively promotes its press-in technology worldwide and contributes to the construction industry by proposing and implementing innovative solutions. The innovative press-in technology provides a unique solution and the adoption of this technology has spread to over 40 nations and regions.
If you have any questions regarding the news release, please feel free to use the provided form to inquire.
Contact Us