MILLENIUM DOME,GREENWICH

INTRODUCTION

Vision of the project

Built to celebrate the arrival of new millennium in 2000

•Architect-Richard Rogers

•Structural Engineer-Buro Happold

Period of construction-1996-2000

Project cost-758 million pounds

Building Category-Exhibition and assembly

LAYOUT

Diameter-320 meters

Central height-48 m

Enclosed area-80,000 sqm

(20 acres)

Capacity-40,000 ppl

Main design challenges:

•Long span

•Lighting for the enclosed

spaces

Development of tensioned straight cables -History

•The elimination of one set of cables brings with it

the removal of cross clamps and anchorages

•Whether the load is acting downwards or upwards,

the cable is tensioned in the same direction, which

can be a great advantage if this tension is taken

by a funicular arch or ring beam

•With just one set of cable, connections between

the fabric cladding and cable can be greatly

simplified which results in easier roof installation

Simply Suspended Cables

Pre Tensioned Cable beams

Pre Tensioned Cable net

Tensioned Straight Cables-Advantages

LOAD TRANSFER

CABLE RING

CIRCUMFERENTIAL

CACLE

UPPER HANGER

LOWER

TIE

DOWN

STRINGERSCATENARY CABLE

DETAILING-MASTS

•Pyramidal base to suit space planning•Inclination (17 deg) provided on the basis of equilibrium conditions•Rubber pot bearing with a single locating joint to allow rotation

DETAILS-CLADDING MATERIAL

PTFE (polytetrafluoroethylene) coated glass fiber

•Flame resistant•Unaffected by UV light•Water proof and dirt resistant

Needed a translucent fabric roof with insulation

To achieve a light spectrum as close to daylightTo avoid condensation of air within the building

Double layered fabric roofing provided

•To provide a layer of air as insulation•To avoid risks

•The stiffening in the cables is provided by highly pretensioned cables(Each radial cable is subjected to 400 kn-2/3 of the tension capacity)

•Needed because of the long span of the radial cable-150m

•Tapering segments provided due to the reduced stiffness and excessive

deflection under rain and snow loads

•Slope increases with the span of fabric panels.

DETAILS-CABLES

DETAILS-CABLES-”WISH BONES”

Circumferential cables on the fabric roof can lead to water accumulation

Rigid members introduced to keep cablesOff the roof

CONSTRUCTION PROCESS-MAST ERECTION

CONSTRUCTION PROCESS

CONSTRUCTION PROCESS

Arrangement of lifting equipmentin the masthead

Assemble concentric rings of cables on the ground andInstall the individual radial cables between the rings at ground level

Use temporary extension cables attached to the permanent hangers, the rings were pulled up Using three separate cable jacks of each of the 12 masts.

The separate infill radial cables between the circumferential rings were than installed

Finally the cable net was post tensioned.

CONSTRUCTION PROCESS-CLADDING