00936153

Component

https://doi.org/10.3141/1814-12

http://scholar.google.com...GERS&publication_year=2002

In 1994 to 1996, three 9-m-diameter parallel tunnels were constructed crossing below twin existing tunnels at London Heathrow Central Terminal Area station for the Heathrow Express project at Heathrow Airport in the United Kingdom. Extensive monitoring was undertaken during construction. Settlement curves at various construction stages in the existing tunnels were measured. Marked asymmetry was noted in the settlement curves caused by construction of the two outer tunnels. It has been noted by several authors that the surface settlement trough caused by the second of two closely spaced tunnels is markedly asymmetrical. This has been accounted for by the fact that when twin tunnels are closely spaced, the ground in the region where the second tunnel is to be constructed has already been subjected to appreciable shear strains associated with construction of the first tunnel. This reduces ground stiffness, hence a higher volume loss for the second tunnel, producing an asymmetrical settlement trough with settlements greater on the side nearest to the first tunnel. The data from London Heathrow have been added to a database of case histories of twin tunnels prepared from reported information worldwide. A new empirical method was developed for estimating the settlement trough caused by the second of twin tunnels, along with an exercise demonstrating the use of the method, which is proposed for use as a preliminary predictive tool.

This paper appears in Transportation Research Record No. 1814, Design of Structures 2002.

English

Hansmire, W H

p. 103-112

2002

Transportation Research Record

0309077400

Figures (8) ; References (11) ; Tables (2)

Asymmetry; Case studies; Construction; Databases; Empirical methods; Estimating; Monitoring; Railroad tunnels; Settlement (Structures); Shear strain; Troughs (Geology)

Heathrow Airport; London Underground

Twin tunnels

London (England)

Bridges and other structures; Construction; Design; Highways; Public Transportation; I25: Design of Tunnels; I54: Construction of Tunnels

TRIS, TRB

Jan 22 2003 12:00AM

• ADVANCED FIBER-REINFORCED POLYMER-WOOD COMPOSITES IN TRANSPORTATION APPLICATIONS
• CLASSIFICATION OF DAMAGED AND MODIFIED BRIDGE BEAMS WITH VIBRATION SIGNATURES
• COMPOSITE ACTION IN STEEL GIRDER BRIDGE SUPERSTRUCTURES SUBJECTED TO TRANSVERSE EARTHQUAKE LOADING
• CONCRETE BRIDGE DECKS CONSTRUCTED WITH FIBER-REINFORCED POLYMER STAY-IN-PLACE FORMS AND GRID REINFORCING
• CORRUGATED HIGH-DENSITY POLYETHYLENE PIPE: LABORATORY TESTING AND TWO-DIMENSIONAL ANALYSIS TO DEVELOP LIMIT STATES DESIGN
• DESIGNING DISCONTINUITY REGIONS IN STRUCTURAL CONCRETE WITH COMPUTER-BASED STRUT-AND-TIE METHODOLOGY
• DEVELOPMENT OF NEW SMALL-DIAMETER DRAINAGE PIPE
• EFFECT OF DIAPHRAGMS ON LOAD DISTRIBUTION OF PRESTRESSED CONCRETE BRIDGES
• EXPERIMENTAL AND NUMERICAL RESPONSE OF A 1915 RIVETED THROUGH-GIRDER BRIDGE
• FACTORS FOR RATING CONDITION OF CULVERTS FOR REPAIR OR REPLACEMENT NEEDS
• FIELD MEASUREMENTS OF LONG-SPAN CORRUGATED STEEL CULVERT REPLACING CORRODED CONCRETE BRIDGE
• FINITE-ELEMENT MODELING OF REINFORCED CONCRETE ARCH UNDER LIVE LOAD
• FORENSIC INVESTIGATION OF FAILED MAST ARMS OF TRAFFIC SIGNAL SUPPORTED STRUCTURES
• GROUTED CONNECTION TESTS IN DEVELOPMENT OF PRECAST BENT CAP SYSTEM
• HIGH-PERFORMANCE STEEL COST COMPARISON STUDY
• INTERMEDIATE DIAPHRAGM AND TEMPERATURE EFFECTS ON CONCRETE BRIDGE PERFORMANCE
• MODEL SPECIFICATION FOR COMPOSITES FOR CIVIL ENGINEERING STRUCTURES
• MODELING THE RESPONSE OF REINFORCED CONCRETE BRIDGE BEAM-COLUMN JOINTS SUBJECTED TO EARTHQUAKE LOADING
• NUMERICAL LOAD RATING OF REINFORCED CONCRETE COMPRESSION MEMBERS: DEMONSTRATION WITH CONNECTICUT ARCH BRIDGES
• PERFORMANCE EVALUATION OF HIGH-DENSITY POLYETHYLENE CULVERT PIPE
• PRECAST POSTTENSIONED ABUTMENT SYSTEM AND PRECAST SUPERSTRUCTURE FOR RAPID ON-SITE CONSTRUCTION
• PREDICTING DEFLECTIONS IN CONCRETE-FILLED GRID DECK PANELS
• PROFILE-WALL HIGH-DENSITY POLYETHYLENE PIPES 1050 MM IN DIAMETER UNDER DEEP SOIL COVER: COMPARISONS OF FIELD PERFORMANCE DATA AND ANALYTICAL PREDICTIONS
• REHABILITATION STUDY OF TOUTLE RIVER TIED-ARCH BRIDGES
• RISK ANALYSIS AS DESIGN TOOL IN FIRE-SAFETY RETROFIT OF TWO ITALIAN TUNNELS
• RISK MANAGEMENT: ILLUSTRATED CONTRIBUTION OF INSURERS AND REINSURERS
• SAFETY ASPECTS OF FLEXIBLE NEW AUSTRIAN TUNNELING METHOD VERSUS STIFF SHOTCRETE LININGS
• STATIC MEASUREMENT OF BEAM DEFORMATIONS VIA CLOSE-RANGE PHOTOGRAMMETRY
• STRESS-RUPTURE PERFORMANCE OF GLASS-FIBER REINFORCED COMPOSITES