Press-in Method for railway extension project in Minnesota, U.S.A.

26 Feb 2021 NEWS RELEASE

Giken SILENT PILER™ F401-1400 has completed work for a railway extension project※1 in the city of Minneapolis, Minnesota, U.S.A. The project site was adjacent to the existing railway line and was an excellent opportunity to demonstrate the superiority of the Press-in Method. Completion of this project is expected to expand adoption of Press-in Method in railway projects in the United States.

※1 The METRO Green Line Extension will serve downtown Minneapolis and the communities of St. Louis Park, Hopkins, Minnetonka, and Eden Prairie to adapt to the current population growth. The new line is 23.3km from Minneapolis to Eden Prairie. Overall project duration is from 2018 to 2022. The average ridership was 19,000 in 2014. Projected ridership is 34,000 in 2040.

■Details of Press-in Work
The Press-in method was applied to construct the sheet pile retaining wall※2. The installation site was a 859m long cut and cover tunnel and adjacent to the existing railway line.
Two units of the SILENT PILER™ F401-1400 were used to install total of 2,500 Z sheet piles. The sheet pile lengths were 7.6m to 19.8m long, with a total installation distance of approximately 1.7km-linermeter. Our group company, Giken America, supplied the SILENT PILER™ as well as operative and technical instructive personnel to the Contractor.

※2 A wall which retains soil from surrounding areas when excavating the ground.

During Installation

Cross section view

■ Selection Basis
The site is located around a quiet and urbanized residential area with an existing railway line nearby. In conventional piling methods such as vibratory hummer, vibrations and noise can interfere with the lives of residents and surrounding infrastructure. Additionally, safety concerns were expressed on the negative impact on railway operations.
Press-in Method enables the installation of piles without vibration and noise. As the machine grips onto installed piles, where the design and installation is carried out in the Giken prescribed manner, stability of equipment is ensured and safety maintained. This is an ideal application for residential areas and construction near existing rail lines. Giken has extensive experienced in these environments, working on several similar construction sites in Japan and overseas.
For this project, the Hard Ground Press-in Method, which installs piles while augering in by Pile Auger, was adopted due to the presence of large boulders. This method enables installing long sheet piles into hard ground with high accuracy.

■ Further development
This is the second successful project completed using Press-in method near an existing railway line in the United States. Similar projects may be planned in other regions in U.S. in the future. It is expected that this method will be adopted in similar conditions. Continuing on from this success, we will continue actively to promote the Press-in Method globally.

■ Project Video
The Project Owner has released a video on their official YouTube introducing Press-in Method as an innovative solution. Click on below link to access their page.
https://www.youtube.com/watch?v=Efvf7p8Fc-A&feature=youtu.be

■ Project Summary

Project nameSOUTHWEST LIGHT RAIL TRANSIT PROJECT
(METRO Green Line Extension)
LocationMinneapolis, Minnesota, USA
Project OwnerMetro Council-SWLRT (Southwest Light Rail Transit)
Prime contractorLunda/C.S.McCrossan JV
ContractorSame as above
Equipment2 SILENT PILER™ F401-1400 (Hard Ground Press-in version)
Sheet PilePaired Z sheet pile (NZ26, NZ38, NZ38-CP)
Length 7.6m to 19.8m, 1250 pairs (2500 pcs)
Duration Sep. 2019 to Jan. 2021
Contact Information:
GIKEN LTD.
International Business Department
TEL: +81-3-3528-1633 (weekdays: 8:30 to 17:30)
Tokyo Head Office: 16F Ariake Central Tower, 3-7-18 Ariake, Koto-ku, 135-0063, Japan