case study of shards tower - a high rise building

1. TheShardat LondonBridge
Structure Case Study by:
KRITHIKA.N

2. INTRODUCTION
Client: Teighmore Ltd c/o SellarProperty Group
Location: London
ProjectYear: 2009- 2012
ProjectArea: 1,200,000sqft
Height: 1,016ft (310m)
ProjectCosts: £435Million
LeadArchitect: RenzoPianoBuilding Workshop &
AdamsonAssociates
StructuralEngineer: WSPCantorSeinuk
THESHARD

5. DESIGNCONCEPT
THESHARD
Thegoal for the design was to accentuatethe urbanand createastructure that would
blend with theskyline.
Locatedin the center of atransportationhub, TheShard’s aimsto sympathize
with urbanscape.
Sincethe schematicdesign process, geographic conditionswere
designedfor.

6. Residential
62,000 sq ft
Hotel
192,000 sq ft
Offices
594,000 sqft
Retail
61,000 sqft
Restaurant
Offices
THESHARD
Hotel
Spire
Viewing Gallery
Apartment
PROJECTREQUIREMENTS
8,000
44
48
Gross InternalArea
Area of Facade
Population
Lifts
Car ParkingSpaces
1,367,000 sq ft
600,000 sq ft
580,000 sqft
11,000 tons
Volume ofConcrete
Weight of Steel
Glass Panels 11,000

7. THESHARD
● The structural system of the tower is a combination of
different systems. It consists of concrete cores,
composite floors, and steel structural members.
● The Shard Tower has about 54,000 cubic metric tons
of concrete and the steel system has a weight of
about 11,000 tons.
● The core of the tower was made by slip forming. The
core was constructed at a rate of at least 3 meters
per day.
● The steel columns are aligned with the slope of the
Shard Tower.
● The size, weight, and spacing of the columns get
smaller the higher they go up in floors. .
MAIN STRUCTURE

8. THESHARD
MAIN STRUCTURE

9. THESHARD
•The floor framing in the Shardwas altered with height; the
office levels were designed in steel, while the hotel and
residences were framed in concrete. Thetransition did not
exactly match the changeof use; steel construction was
continued up to level 40- sixfloors above lowest part of hotel.
•Thereason for this mismatch was related to the span between
perimeter columns and the low allowable deflections of the glass
façade.
•Thecomposite edgebeamsachieved the required
performance with aspan of 6 but in the concrete levels, the
maximum perimeter columnspacingwas 3m becausedown-
stand beamswere notpreferred.
•Transfer structures were needed in order to achieve the
reduction in spacing,and thesetook the form of three-storey
high vierendeel frames at the top of the steellevels (i.e. from
level 37 to level40).
.
COMPONENTS
Steel FloorSandwich
ConcreteFloorSandwich
Floors

10. THESHARD
“The Spire”
•The‘Spire’ is the 60m tall pinnacleat top of the tower, containing
the public viewinggallery.
• Theconcrete core stops at level 72 and continues asasteel mast.
• The solid floors are replaced by open grids and the shardsstop at
different levels.
•The spire comprises acentral steelmast to provide stability, floor
platesevery third level and the ‘shards’ themselves.
•Theshardsextend past the top floor plate by up to 18 m and are
supported by cantileveringtrusses.
• Thecompressionbooms are restrained by U-frame actionfrom
the trussesacting together with the framesin the plane of the
facade.
•The wind tunnel test on the spire checkedthe structure for any
resonantor ‘galloping’ effects from wind gusts.
.
TheSpire
COMPONENTS

11. ● Where bolted connections couldn’t be avoided, the architect worked
with the steelwork contractor to dress the connections with cover
plates. For example, on the connection between the vertical,
horizontal and diagonal bracing Severfield-Reeve produced curved
plates.
● Other connections were dressed with filler after erection, and over-
coating such as those on the wing walls, which have flush welds or
CONNECTIONS
THESHARD

12. Loadfrom
concrete
part=12701.41
kips
Loadfrom steel
parts=2486.9005
kips
The Shard tower includes 5800 m2 of residential, 17800 m2
Hotel, 55200 m2 office space and 5600 m2 retail stores. This
volume contains 54000 m3 concrete as well as about11,000
to 12,500tons of structural steel.
The weight of live objects and movable parts such as
furniture, as well as wind load and seismic load(lateral
loads which we will discuss it in a different section) are
considered live load.
All this masscreates a
deadload that needs
to becalculated.
THESHARD
DESCRIPTIONOF
LOADS

13. In order to makeit asefficient aspossible, the
changein perimeter columnspacingfrom 6m to
3m was achieved by using Vierendeeltrusses.
USING
VIERENDEEL
TRUSSES
At the junction of the main tower with the backpack(the office space
extension which is 19 stories high), the spacing of columns was
increased to 12m. The reason is becausethey wanted to avoid awall of
columns interrupt the office spaces.Here, they usedsimple but very
largetrusses.
DESCRIPTIONOF
LOADS
THESHARD
TRANSFER OFLOADS

14. COLUMNS
Theychosecranked,y shapedperimeter columnsat
first, but thenchangedtheir
decision to the simplicityof direct line. Because it was
better both aesthetically andeconomically.
THESHARD
Loading the columns at ground level
DESCRIPTIONOFLOADS

15. The relative magnitudes of the total
Dead loads:2.15 x 108 lb
Live loads: 9.60 x 107 lb
and Horizontal loads: 6.08 x 108 lb
respectively. These numbers imply that the structural
systems for this building must resist extremely high
external and internal loads due to its grand scale and
unusual geometry.
THESHARD
Multiframe
Analysis
Forces and Shear

16. Moment and Deflection
THESHARD
Multiframe
Analysis
The relative magnitudes of the total
Dead loads:2.15 x 108 lb
Live loads: 9.60 x 107 lb
and Horizontal loads: 6.08 x 108 lb
respectively. These numbers imply that the structural
systems for this building must resist extremely high
external and internal loads due to its grand scale and
unusual geometry.

17. ● Buildingis composedof four material layersvertically.
● Layeringof structural materialsgivestability where
needed.
● Theconcrete section from levels 41 to 69 providesmass
dampers to minimize oscillations and stiffness to the
building.
● Aconcrete core running provides lateralstability.
● Provides vertical rigidity and allows for minimalfloor
platesshift.
LATERALSYSTEMS
Layering of StructuralMaterials
THESHARD

18. • London hasageologytypical soil at this area.
• Thewater table is at the top of the gravel.
•Tectonic plate under neath ground layers effect wasto
makethe eastern piles afew metres deeper.
SOILANALYSIS
THESHARD
Description

19. •Movement monitoring, vibration, ground water and reuse
of old piles were taken into account in designing
foundation.
•Top-Down construction methodology wasusedin
construction.
• Plunged columns usedto supported core andTop-down
slabs.
•Theslab underneath the core has3m thicknesswith four
layers of reinforcement in eachdirection to provide
stiffness.
FOUNDATION
THESHARD

20. •Theground slab wascaston aslip membrane so
that blinding concrete did not adhere to the
underside.
• Excavation of two levels of basement then took
placebeneath the ground floor slab.
•Meanwhile, the slab for level B2wascast.
Excavation continued beneath B2to formation
level.
•Theslipform wasnot allowed to climb above level
21 while the core wassupported on plunge
columns only.
•Theraft slab wasinstalled in asingle5500m3
pour taking 32 hours. Up to this point, all loads
were carried on the secantwall and the piles
containing plunge columns.
EXCAVATION
THESHARD