Podium monumental steps sydney opera house

Engineering Case Study

ROOF SAILS

PODIUM

UNDER GROUND LOADING DUCKS

NORTHERN BROADWALK

WESTERN BROADWALK

EASTERN BROADWALK

MAN 0’WAR STEPS AND JETTY

CONCRETE HALL SHELLS

MONUMENTAL STEPS FORECOURT LOWER CONCOURSE

Structural estimate

• There were significant changes to the original plans of the Sydney Opera House. Also, the construction was commenced before the finalized designs.

• Elements erection – highly advanced methods (post-tensioning for shells).

Roof Sails:

• Most recognizable part of the Opera House. • Due to full exposure to marine environment, There might be

failure in ceramic tile skin or for grouting inside the post- tensioning ducts.

• So, more focus should be given to investigate the structural performance.

Tile lids:

• Concrete ribs in the sails clad in 3382 chevron shaped tile lids which hold ceramic tiles in place.

• A new approached was developed for the tile lid to achieve 3D spherical geometry of the frame work.

• Thin acrylic flat mesh gives adjacent support for the surface.

Structural estimate

Lower concourse: • Completed in 1988. • Original intention was to provide with covered access and facilities

supporting the Opera House • Sea wall treatment and the configuration of Lower Concourse

became highly successful.

Concrete conservation: • Opera house regularly monitors & prevents the corrosive maintenance of

concrete and other fabric • Purpose – long lasting strategies for concrete. • Dr. Nutt worked for the structural engineering helped to focus the areas

for concrete conservation.

Roof Shells: • All the roof shapes are derived from the single sphere, which shares the common

radius. • The design solution for the shells was a major feat by ultzon and ove Arup & partners. • Intensive efforts were made to hold self sustaining without reinforcement

Structural estimate

Roof Pedestals: • Roof pedestals are steel reinforced concrete structures at the base of the roof

sails, exposed to natural elements. • Due to rainwater runoff, erosion and biological growth can be noticed. • Protective coatings and other measures became inefficient. • Pedestals became high heritage significance.

Broad walks: • There are 3 types of broad walks:

Northern broad walk Western broad walk Eastern broad walk

• Western and Northern broad walks rest on steel reinforcement concrete piers. These piers are embedded into harbor floor.

• Granite aggregate slabs used to clad the broad walks.

Podium: • Its construction became an engineering event. • Purpose – continuous reinforced concrete which rises

from the ground and overlooks the harbor.

Structural estimate

Underground loading docks: • There is an underground loading docks under

the covered concourse accessed through tunnel entry from the south-western side of the forecourt.

• Loading equipment, barriers are painted in bright yellow for indication.

Glass wall: • Glass wall – an engineering achievement. • The construction of glass wall took 8 years to

complete. • Extensive research was conducted to test the

limits of glass wall i.ie load bearing.

Structural estimate

Tolerance of change reference to the ability to adjust changes in structural elements. 1 = Low tolerance 2 = Moderate tolerance 3 = High tolerance

Tolerance for change

ELEMENT TOLERANCE FOR CHANGE FURTHER CONSIDERATIONS

Form Fabric Function Location

ROOF SHELLS

Glazed tiles 1 1 1 1 Replacement and maintenance should be done where necessary.

Tile lids 1 1 1 1 Maintenance and replacement of tile lids are done at necessary places.

Glass walls and supporting structure

2 2 1 1 Minor modifications are permitted instead of replacement.

Nose lights on shells Intrusive

LOWER CONCOURSE

Paving, steps and walls of solid granite

2 2 1 2 Surface finishes of the materials are worth retaining.

Seawall footpath of granite setts

3 2 1 2 Material may require reappraisal to match repaved forecourt.

Louvered circular ceiling lights 1 2 1 1 Should be retained as a part of the original design.

Structural estimate

Element TOLERANCE FOR CHANGE Further considerations

Form Fabric Function Location

Podium

Monumental steps 1 1 1 1 Configurations in Utzon’s approach sequence are more important. Retain unaltered.

Bronze framed glass to openings 2 1 1 2 For alteration, use the bronze metal.

Added acrylic panels to lower part of guardrails

Intrusive Address safety issues for exploring the alterations.

Broad walk

Large-scale precast granite seawall skirting panels

2 1 1 1 Individual precast units can be change but the bottom panels must be retained.

Supporting pile structure 3 3 1 2 Broad walk structural function is essential.

Marquee function hall Intrusive Remove entirely.

Underground loading dock

Lifts to Joan Sutherland Theatre scenery dock and concert hall backstage

3 3 1 1 Critical function.

Basement offices 3 3 3 2 Ideal location for contractor offices and facilities.

Service and plant areas 3 3 2 2 Operational efficiency is important.

Structural estimate