THE SHARD -LONDON

TOPIC: STRUCTURAL SYSTEMS OF TALL BUILDINGSSUBJECT: CONSTRUCTION TECHNOLOGY- VFACULTY: PROF. S.P.SAPRE

INTRODUCTIONThe Shard (also referred to as the Shard of Glass

, Shard London Bridge or the London Bridge Tower is a skyscraper in London, England.

Standing 309.6 meters (1,016 ft) high, it was topped out on 30 March 2012 and opened on 5 July 2012.

The Shard is the tallest completed building in Europe, and is also the second-tallest free-standing structure in the United Kingdom, after the 330-metre (1,083 ft) concrete tower at the Emley Moor transmitting station.

The Shard replaced Southwark Towers, a 24-story office block built on the site in Southwark in 1975.

Renzo Piano, the Shard's architect, worked with the architectural firm Broadway Malyan during the planning stage.

The tower has 72 habitable floors, with a viewing gallery and open-air observation deck – the UK's highest – on the 72nd floor, at a height of 245 metres (804 ft).

The Shard was designed with an irregular pyramidal shape from the base to the top, and is clad entirely in glass.

Its structure was completed in April 2012.

The Southwark Towers office block, which was demolished to make way for the Shard

Piano drew inspiration for the project from ship masts and church spires.

The elongated, pyramidal form of the building came to Piano at his first meeting with Sellar and developed into an eight-sided tower with angled glass facades that don't quite touch one another.

Using ultra-clear, low-iron glass was critical to the scheme.

Too often tall buildings are opaque and mysterious. Hence Piano wanted this one to be transparent, so everyone could see all the activity inside. And by angling the glass, the tower reflects views of the sky.

The building is an expression of the weather in London, changing all the time

General details :-Location: 32 London Bridge Street,

Southwark, London, EnglandClient: Teighmore LtdSize: 87 storeys; 93 000 sq mConstruction started: March 2009 Completed: July 2012 Cost ~ £450 millionHeight with Antenna spire: 309.6 m

(1,016 ft) Roof :304.1 m (998 ft)

Technical Details:Floor count :95 (Including plant floors), 72

(habitable) Floor area :110,000 m2 (1,200,000 sq ft) Elevators: 44 DesignConstruction Architect :Renzo Piano Developer Sellar Property Group Structural engineer Turner & Townsend (Project

Managers), Structural Engineers : WSP Cantor Seinuk Concrete temporary works : Robert Bird Group Services engineer : Arup Main contractor : Mace

In terms of its structure, the Shard stacks a series of different systems on top of each other—starting with a concrete foundation, then a steel frame for the office floors and the public spaces of the hotel, then another concrete frame for the hotel guest rooms and the residences, and finally a steel frame for the observation galleries and the building's unoccupied top. It may seem odd to put a concrete structure on top of a steel one, but the arrangement reduces the building's sway, says William Matthews, the project architect for Renzo Piano Building Workshop. To speed construction, the contractor used a “top-down” process that began with a concrete platform at ground level, then built up at the same time as the foundation was being erected below. The process was more expensive, but it cut six months from the schedule.◦   

Because London provides no real context or common vocabulary for skyscrapers, the Shard must work as a solo performer, graceful enough to hold public attention over time.

On a typical day in April, it changed personality along with the mercurial weather: gray and moody when surrounded by clouds, dashing and a bit roguish in sunlight.

Architectural details :At 1,016 feet and tipped to be the

tallest building in Europe, the Shard will provide 900,000 square feet comprising office space, hotel, residential apartments, restaurants and viewing galleries with unparalleled views of south east England.

Renzo Piano, the project's architect proposed a sophisticated use of glazing, with expressive façades of angled glass panes intended to reflect sunlight and the sky above, so that the appearance of the building will change according to the weather and seasons.

It features 11,000 panes of glass.

The Shard’s early conceptual designs were among the first in the UK to be progressed following the publication of the US National Institute of Standards and Technology (NIST) report into the WTC collapse.

The building was designed to maintain its stability under very onerous conditions

The Shard contains premium office space, a hotel, luxury residences, retail space, restaurants, a five-storey public viewing gallery, and a spa.The public viewing gallery is located on the 72nd floor, at a height of 245 metres (804 ft)

The building will complement the irregular nature of the site.

Each façade of the building is a flake of glass tending inward and rising to the top, resembling a glass pyramid.

The top corner of the tower is open as the glass shards or flakes do not touch each other. This is conceived as the breathing space for the tower.

Geometry :The shape of the tower is generous at the bottom

ground and n without arrogantly touching the ground and narrow at the top , disappearing in the air like a 16th century pinnacle or the mast top of the ship.

The tall,slender,multifaceted and tapered geometry of the building was a great challenge for the structural designers.

The tapered geometry efficiently accommodates the various usages along its height such as residential at the upper portion with smaller floor areas, hotels at the mid height portion with average floor areas and commercial at the lower level called “backpack”, to further increase the commercial floor areas.

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The challenges were to create a harmonious structure systems, while addressing the often conflicting requirements of multiple programs like selecting the appropriate lateral load and gravity load bearing structural systems, while creating an economical and constructible design.

From the early stages of the design and conception, the effort had been made to support the architect's impression of the building and to use the state-of-the-art structural engineering and construction techniques to include every aspect of the building from foundation to its gravity and wind/seismic resisting systems.

Key features of the structural system include the use of top-down basment construction for the main tower with conventional bottom up construction under the low rise annex “backpack” portion of the building on the east side.

This methodology was adopted to increase the speed of construction and to minimize the ground movements around the site.

Top-down construction is an alternate method of construction where, after installation of the the load bearing elements such as diaphragm walls and piles, the basement floors are concreted as the excavation progresses from grade level down to lower basement level.

Structural Details :Due to the sensitivity of the adjacent

infrastructure ,the main focus for the foundation of this building was to minimize the ground movememnts during construction, while working through the existing foundation of the previous structure and other obstructions.

A foundation system of a perimeter secant pile wall comprising of 900 mm diameter piles and 1500 mm diameter bore piles 50 meters deep using a top-down construction methodology was done.