WIDENING THE LOAD AT NAZZANO

This article describes a new tunnel widening technique that allows traffic to continue to flow during construction work. The technique is being used to widen the Nazzano road tunnel in Italy from two to three lanes, with additional emergency lanes in each direction. . A steel traffic protection shell, situated above the traffic and lined with sound proofing and anti-shock materials, allows the tunnel to remain operational during construction. Primary features of the technique include using a segmental final lining to stabilize the widened tunnel that is put into place according to the "active arch principle" that becomes operational at a distance of 4m-5m from the widening face. Because of this technique, passive stabilization operations such as shotcrete and steel ribs are not needed. If necessary, ground improvement can be taken care of ahead of the widening. The article describes where the new widening technique originated, its three stages of construction, how the technique is being used at the Nazzano tunnel, and the benefits of using the technique.

Availability:
- Find a library where document is available. Order URL: http://worldcat.org/issn/0041414X
Corporate Authors:
Polygon Media Limited

Tubs Hill House, London Road
Sevenoaks, Kent TN13 1BY, United Kingdom
Authors:
- Lunardi, P I
Publication Date: 2003-7

Language

English

Media Info

Features: Figures; Photos; References;
Pagination: p. 16-19
Serial:
- Tunnels & Tunnelling International
- Volume: 35
- Issue Number: 7
- Publisher: Progressive Media Markets, Ltd
- ISSN: 0041-414X

Subject/Index Terms

TRT Terms: Excavation and tunneling; Fiberglass; Safety; Shotcrete; Soil stabilization; Vehicular tunnels
Geographic Terms: Italy
Subject Areas: Construction; Geotechnology; Highways; Safety and Human Factors;

Filing Info

Accession Number: 00962290
Record Type: Publication
Source Agency: UC Berkeley Transportation Library
Files: BTRIS, TRIS
Created Date: Sep 2 2003 12:00AM