About construction of Kumasaka tunnel construction of Joshin-Etsu Expressway (between Toyota Iiyama IC and Shinanomachi IC)

Corporate Top
Press Room
Press Release　Niigata office
About construction of Kumasaka tunnel construction of Joshin-Etsu Expressway (between Toyota Iiyama IC and Shinanomachi IC)

Return to search results for press release (Niigata Regional Head Office

January 24, 2008
East Nippon Expressway Co., Ltd.
Niigata Regional Head Office

NEXCO EAST Niigata Regional Head Office (Nishi-ku, Niigata city, Regional Head Office president: Yoshio Shiraishi), due to inappropriate construction by the contractor in the Joshinetsu Road 4-lane project (between Toyota Iiyama IC and Shinanomachi IC) currently under construction, We confirm the construction failure such as the thickness of the lining concrete for the tunnel being insufficient, and we are reconstructing it. (See attached sheet [PDF:394KB])

1 History

We received a report from the contractor that the thickness of the lining concrete in the tunnel was insufficient and that there were voids.

As a result, we confirmed that the thickness of the lining concrete was insufficient and that there were voids in some areas.

It was also found that the reason for such a construction failure was that the construction contractor did not report the matters to be reported to us, but carried out the construction at the contractor's own discretion.

2 Tunnel name

Kumasaka Tunnel Nagae Prefecture Nakano City

3 Outline of construction contract

Construction name
Joshin-Etsu Expressway Kumasaka Tunnel Construction

Contractor
Mitsubishi Corporation, Kitano Construction Co., Ltd.

Construction period
June 22, 2005-December 8, 2007

4 Other

We are currently reconstructing the defective parts and are planning to complete them by the end of March.

In addition, it does not affect the service period of the four-lane Joshinetsu Expressway (between Toyota Iiyama IC and Shinanomachi IC) scheduled for 2009.

Image image of image link (external link) to download page of Adobe Acrobat Reader

To view the PDF file, you need the Adobe Systems plug-in software "Acrobat Reader (Japanese version)". If you do not have Download from here (free)Please use it.