Gyropress Method™ Employed for Disaster Recovery Work at Site of Large-scale Landslide at Ichinose-machi in Wajima-shi

GIKEN LTD. sends prayers and best wishes to everyone affected by the 2024 Noto Peninsula Earthquake and the 2024 Oku-Noto Heavy Rains.

The Gyropress Method™—a method for rotary cutting press-in of tubular piles—of GIKEN LTD. (Head Office: Kochi-shi, Kochi; President and CEO: Atsushi Ohira) was employed in disaster recovery work at Ichinose-machi (in Wajima-shi), where there was extensive damage due to a large-scale landslide. Over a period of approximately two months starting from December 2024, group company GIKEN SEKO CO., LTD. (Head Office: Kochi-shi, Kochi; President and CEO: Akihiro Nishigawa) built a retaining wall extending 77 m using tubular piles to prevent further landslides. This ensured safety for smoothly carrying out future full-scale construction of disaster countermeasures such as check dams.

A river running through a mountainous area flows through the site. It is also the place where a landslide dam was created from a major river obstruction after a landslide caused by the earthquake. As the soil is mixed with fallen trees and boulders from the landslide as well as metals, fast and efficient work was achieved using the Gyropress Method™, which can penetrate even hard ground.

There are many other similar sites all over the disaster-affected areas. In March 2025, the GIKEN Group increased the number of employees at the Noto Reconstruction Support Office and also relocated its office. Through reinforcing the structure, the group will contribute toward further accelerating the recovery and restoration of the disaster-affected areas.

The site is located in Ichinose-machi, a disaster-affected area that suffered especially severe damage. The mountain slope collapsed from the ridge, creating a large-scale landslide that flowed for approximately 1 km, devouring several houses and roads. The government is working urgently on recovery. The GYRO PILER™ F401-G1200 was employed for the work, which entailed pressing in 78 tubular piles measuring 11.5 m to 16.5 m in length and 800 mm in diameter. A retaining wall extending 77 m was constructed.

Concerns regarding a prolongation of construction time when using other construction methods
When building a retaining wall using blocks and such, a lot of excavation is required, extending the process. Even for other construction methods using tubular piles, there were concerns regarding a prolongation of construction time due to the low certainty of penetration should a pile hit a buried object.

■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.