Oodi Helsinki Central Library - Teräsrakenneyhdistys
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Oodi Helsinki Central Library
Transcript of Oodi Helsinki Central Library - Teräsrakenneyhdistys
Oodi Helsinki Central Library
RAMBOLL
Germany:14 offices
Switzerland:1 office
Canada:2 offices
UAE: 2 offices
India:10 offices
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Norway: 17 offices
Sweden:30 offices
UK:16 offices
US: 77 offices
Qatar:1 office
Saudi Arabia:1 office
Spain:2 offices
France:4 offices
Finland:34 offices
Brazil: 3 offices
Russia:1 office
Poland:3 offices
NL: 2 offices
Belgium:3 offices
Italy:2 offices
Romania:1 office
Singapore:2 offices
South Africa:1 office
Australia:3 offices
Myanmar1 office
China:4 offices
Greenland: 2 offices
Indonesia:1 office
Malaysia:1 office
Mexico: 2 offices
Mozambique:1 office
Cyprus:1 office
New Zealand:1 office
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RAMBOLL IN FINLANDSINCE 1962
25 Ramboll sites
3
227 M€(2018)
42 M€Project Management
& Real Estate Consulting
76 M€Infrastructure & Transport
25 M€Environment
and Health
74 M€Buildings
8 M€Water
2 M€Management Consulting
2,400 experts
Our advice and service offering covers every stage of the project life cycle in the built environment.
▪ 2013 Architectural Competition Winning Entry by ALA architects
▪ Architectural Concept
▪ Architectural Concept
PROJECT TEAM:
▪ Helsinki City (Client)
▪ Ramboll CM (Client’s Consultant)
▪ ALA Architects (Architect)
▪ Ramboll Finland (Structural Engineer)
▪ Finnmap Infra / SIPTI Infra (Geotechnical Engineer)
▪ Sweco (Third Party Checker)
▪ EM Pekkinen (Phase1 Main Contractor)
▪ YIT (Phase2 Main Contractor)
▪ Normek (Steel Sub-contractor)
▪ + others
▪ General and Detailed Design, and Construction 2014-2018
▪ Architectural competition draft structural solution:
▪ a mega-truss backbone with additional stiffening truss, complemented by space-frame roof supported off random isolated columns
▪ -> A starting point with significant issues associated with very Finnish influences
▪ Designing for significant snow load
▪ Designing for cold conditions
▪ As well as too confident of a structural solution
▪ -> an immediate need to take steps to re-innovate the structure
▪ -> development of an arch solution, maximising structural effectiveness
▪ In the process of developing a solution that can deliver the architecture, additional advantages are derived:
▪ Better distribution of spans
▪ Clearer corridor zone
▪ Better distribution of structural stiffness
▪ More efficient design potential
STRUCTURAL DESIGN:
▪ Eurocode Suite + Finnish National Annexes
▪ Reliability Class 3
▪ Fire design R60
▪ Consequence Class 3b
▪ Structural Steel Main Frame
▪ EXC3 / EXC4
▪ Concrete Floor Slabs
▪ 2nd and 3rd floors provide plan restraint
▪ Concrete Cores
▪ Cores 1, 2 and 3 are primary supportive
▪ Tendons in cores and floors
▪ for key tension load paths
▪ Glass Walls
▪ Wood Cladding to Walls and Ground Floor Soffit
▪ Wood Roof
▪ The arch-supported building not only serves an architectural purpose, but also serves other practical purposes, such as allowing a future tunnel to be built just below the ground floor slab without impacting on the load-carrying performance of the building.
▪ Steel, concrete, glass and timber have been optimally built in to and harmonised with each other within the design.
▪ Optimised use of hidden spaces to accommodate HVAC and services as well as the structural frame.
▪ 3D geometrical modelling has been essential for successful design coordination.
▪ 2400t of EXC3+EXC4 main frame steel structures.
▪ 970t of steel in the primary arch bridge structure.
▪ up to 120mm thick steel plate.
▪ Tied twin arch bridge with 109m span supports two main floor levels and the roof, as well as an extended balcony cantilevering up to 17m from the front arch, creating a large open column free space at ground level.
▪ Structural vertical depth of approx. 11.5m.
▪ Arch geometry with built-in imperfection of up to approx. 600mm.
▪ Front arch is 1.6m wide 1.6…2.4m tall box girder.
▪ Rear arch is 1.2m wide 1.4…1.8m tall box girder.
▪ 17 tendons link arch bases, designed for 115MN tension tie force.
▪ Front arch inclined at 12.5degs to support the front of the building and the cantilevers.
▪ Whole structural frame is an integral structural solution.
▪ Rear arch inclined at 22.5degs to create a rear support to the cantilevers, to divide the span, and to assist with stabilising the front arch.
▪ Horizontal stability provided by tie-back tendons to the rear concrete cores installed into the floor levels, and tie-down tendons to rock installed into the rear walls of the rear concrete cores.
• The front arch is positioned as far forward as possible
• Its height is tuned to fit into the available space with maximum height where needed
• The height of the arch box section is varied according to applied forces and moments
• The rear arch balances structural spans between front arch and rear of the building
• The rear arch acts in part as a counterbalance to the cantilever
GETTING THE MOST OUT OF THE MAIN BRIDGE STRUCTURE:
ECONOMY WITHIN A GEOMETRICALLY COMPLICATED STRUCTURE:
• Introduce structures that are familiar to the market
• Minimise as much as possible the amount of complicated structures
• Use standard familiar beams as much as possible (WQ beams + OL for floors, and I beams for roof)
• Simplify the arches as much as possible
• Planar
• Regular (uniform width, flat plates, uniform plate thicknesses (PL60 and PL100),…)
• In this case: fully effective sections without longitudinal stiffeners -> clean structures -> helps with internal platework for transfer of forces crossing the section
▪ Arch bases
▪ Common base units for the two arches
▪ Box slab structures sitting on linear bearings
▪ To transfer horizontal forces directly from arches to the ends of the tie-slab tendons whilst providing a load path for vertical forces down to the linear bearings
▪ Tie-slab tendons tensioned in 3 stages, with the first stage applied before erection of the arches, and the last stage applied after substantial loading.
▪ Theatre room with column-free space below seating area. Two heavy-weight trusses supported off spanning concrete walls provide support load paths.
▪ Arch boxes designed without longitudinal stiffeners, but with diaphragm plates. Stiffeners provided where required for transfer of local forces across the boxes.
• Tender Scheme
• site assembly (lift, position, secure, weld) in 12no. pieces
• 18m length max. 85t
• Temporary Works Structures
• Scheme feasibility reviewed with steel contractors at “vuoropuhelut”
• Contractor opted to follow the Tender Scheme
• Lifting Contractor: HAVATOR
• Terex/Demag CC2200
• (SWSL 42+30) 109t@14m
• Quality: Erection Scheme for approval
• Quality: Weld WPS (Work Procedure Specs)
ARCH ERECTION SCHEME:
▪ Site after first arch segments lifted
▪ Arch segments lifted onto temporary works support structures which provide support off strong points in the permanent works.
▪ Arch Jack-down
▪ careful planning of sequencing to manage risk in relation to overloading the permanent works
▪ Arch Jack-down
▪ careful planning of sequencing to manage risk in relation to overloading the permanent works
▪ Temporary works support structures removed before placing the precast concrete floor elements.
▪ Trusses and inter-arch trusses, up to 23m long and 5m tall, with WQ-section top chords and WQ-section bottom chords for 2 hollow core floor levels
▪ Site after before lifting the 3rd floor hollow core slabs
▪ Site after completion of the roof structure
▪ 17m long 2m tall central slender cantilevers
▪ Limited Area accessible to the General Public
▪ Steel diaphragm plate structure with stiffened deck plating
▪ 1-span stiffened deck plating outside insulation envelope
▪ Balcony area -> Vibration Sensitive Structure
▪ -> User comfort
▪ Cantilevers. Example of local detail FE studies.
▪ Load bearing structures are hidden behind wood element and wood clad facade.
▪ The lobby area before installation of wood cladding and the glass wall
▪ The 3rd floor before installation of soffit and glass walls. 12m span insulated wood roof panels on steel frame.
▪ Fin and panel glass walls varying in height up to 8m tall. West wall on 3rd floor supported off flexible level.
▪ Insulation wood wall elements and wood cladding
▪ Two spiral feature staircases designed with sufficient stiffness for user comfort but enough flexibility not to interfere with the main structural system
▪ The building was delivered to the Client to the agreed timetable and budget, without compromising the architectural vision.
