Arched cut-and-cover structure and method of its construction

Abstract

A cut-and-cover concrete tunnel structure (10) is provided with a lower concrete part (2) and an upper concrete or steel part (3) of the structure. The lower part (2) of the structure is constructed in unreinforced concrete, poured directly against and supported by a partly horizontal, partly inclined and approximately circular or elliptically shaped excavation surface (6′). The upper part (3) is arch shaped, constructed in reinforced (cast-in-place or precast) concrete or steel, and is of circular, elliptical or partly elliptical shape. This cut-and-cover structure allows a more efficient and less costly tunnel construction.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a National Stage application of International Patent Application No. PCT / CH2016 / 000011, filed on Jan. 21, 2016, which claims priority to Swiss Patent Application No. CH 200 / 15, filed on Feb. 13, 2015, each of which is hereby incorporated by reference in its entirety.TECHNICAL FIELD[0002]The present invention relates to the general art of bridge, tunnel and geotechnical engineering—and to the particular field of the design of overfilled structures such as arched cut-and-cover structures or tunnels. In particular the invention relates to a cut-and-cover structure providing a tunnel or tunnels for rail or road traffic or pipe lines, conveyor belts or cables. Further, the invention relates to a method for the construction of such cut-and-cover structures.BACKGROUND[0003]Frequently, earth overfilled structures—in cast-in-place or precast reinforced concrete—are used for cut-and-cover traffic tunnels. These allow a railway l...

AI Technical Summary

Benefits of technology

The present invention provides a method for designing and constructing cut-and-cover tunnels that reduces construction costs and impact on the environment. The method includes using an arched surface and unreinforced concrete for the lower part of the structure, eliminating the need for expensive reinforcement materials. Additionally, the invention includes replacing waterproofing membranes with less expensive measures such as waterproof concrete and providing emergency connection openings for maintenance and sheltering purposes. The overall cost of the cut-and-cover tunnels is significantly reduced, making it useful for high-speed or conventional railway lines.

Problems solved by technology

It is well known that—due to the working space required for the formwork on the outside of the structure—these types of cut-and-cover tunnels and bridges exhibit large excavation and backfilling volumes, leave large footprints at the original ground level and usually require expensive foundations in reinforced concrete as well as costly waterproofing measures.

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