1. BEIJING NATIONAL STADIUM
ARCH. HERZOG + DE MEURON
STUDY OF LONG SPAN STRUCTURE
YUJIN HONG + ALAN CHU
Hello, my name is Yujin, and I am Alan. For this long span structure project, we decided to present Beijing National Stadium by Swiss architecture team, Herzog & De Meuron, located in Beijing of China.

2. A BRIEF LAYOUT STRUCTURAL ENGINEER COST ARCHITECT LOCATION SIZE
Herzog & de Meuron, Stefan Marbach
Ai Weiwei, Li Xinggang
STRUCTURAL ENGINEER
Arup Group Limited (ARUP)
LOCATION
South of the centrepiece Olumpic Green, Beijing, China
COST
428M USD
SIZE
330M X 220M X 69.2 M (LxBxH)
CAPACITY
91,000 seats
A BRIEF LAYOUT
this stadium has a nickname of Bird’s Nest due to the web of twisting steel sections that form the roof,
It was a joint project designed by Herzong & De Meuron, with project architect Stefa Marbach, artistic consultant Ai Weiwei and CADG led by chief archituect Li Xinggang
Located at the south of the centrepiece Olympic Green of Beijing in China
With the enormous size of 330m x 220m x 69,2m accommodating up to total of 91,000people.

3. DESIGN USE: Basic structure: Symbol:
2008 Summer Olympics and Paralympics
2022 Winter Olympics and Paralympics
Basic structure:
two independent structures, standing 50 feet apart: a red concrete seating bowl (an egg in a bird’s nest) and the outer steel frame around it.
Symbol:
“great nature” on the earth which is greatly influenced by the Chinese culture, showing the coexistence of the Olympic Games and nature.
The roof inspired by yin yang, the Chinese philosophy of balance and harmony.
The stadium was designed for use throughout the 2008 Summer Olympics and Paralympics and will be used again in the 2022 Winter Olympics and Paralympics, but is currently unused.
The stadium basically consists of two independent structures, standing 50 feet apart:one of them is a red concrete seating bowl that is similar to an egg in a bird’s nest and the outer steel frame around it with the shape of bird’s nest.
The configuration of the Beijing National Stadium is meant to symbolize “great nature” on the earth which is greatly influenced by the Chinese culture, displaying the concept of the coexistence of the Olympic Games and nature.

4. CONSTRUCTION Major Challenge Long span structure Earthquake-resistant
Eco-friendly
CONSTRUCTION
This design was a really big challenge.
Firstly, they had to construct a long span structure in order to build a stadium accommodating 91,000 people. Secondly, it had to be earthquake-resistant, due to the fact that the stadium is located right in the middle of a seismic region. So it must be strong enough to withstand dangerous earthquakes, and lastly it must be eco-friendly, because it was officially mandated that it’d been the green Olympics.

5. CONSTRUCTION a) Long span structure
Steel roof
24 main columns (1,000t)
Tangent to the ellipse
300m long by 220m wide space
Inclined
Reinforced concrete
Precast concrete
The stadium is supported by 24 main columns of 1,000t each that are tangent to the ellipse of the steel roof spanning a 300m long by 220m wide space. The façade’s external surface has an inclination of approximately 13degrees to the vertical. The engineers utilized reinforced steel beams to strengthen the concrete, and L-shaped precast concrete were put between the reinforced concrete to make up the section of the middle and upper tiers.

6. CONSTRUCTION a) Long span structure
These two photos show the reinforced steel beams and the reinforced concrete, that are used for inclined façade exterior.
Use of reinforced steel beams to strengthen the concrete

7. CONSTRUCTION a) Long span structure
After completing constructing the concrete seating bowl, then the steel frame is constructed.
The first set of beam is on the outside; 24 pillars in the form of trusses encircling the concrete bowl, serving as the bones of the structure.

8. CONSTRUCTION b) Earthquake-resistant
Separation of two structures
Concrete Bowl
Divided into 26 isolated independent sections
Steel Frame
50ft apart from the inner structure
The shaking of earthquakes could result in a huge damage to rigid buildings like those made with concrete. So, the engineers decided to build the steel frame as a separate structure without touching the concrete bowl within. So that even if the concrete bowl cracks, it would not affect the steel frame. They also divided the bowl into 26 isolated sections that can move independently. So it there is an earthquake in one section, people would be able to evacuate to another section.

9. CONSTRUCTION c) Green Features
High-tech Membrane
ETFE(EthyleneTetrafluoroethylene) panels
Sunlight in – energy conservation
Keep noise in
Keep wind and rain out
Open Façade Exterior
Natural ventilation
CONSTRUCTION c) Green Features
To fit the green mandate, the steel roof is skinned with high-tech membrane called ETFE panels, which let in the sunlight to conserve energy, keep the noise in and the wind and rain out. The façade of the building isn’t enclosed allowing natural ventilation.

10. STRUCTURE – BUILDING LOADS
DEAD LOADS
Total structure weight (w/o spectators) = 45,000t
Weight of steel = 42,000t
Weight of seats = 91,000 x 8 lbs = 728t
Internal systems and partitions = 5% of weight of internal structure = 150t
Weight of concrete = 2,122t
LIVE LOADS
Vertical live load = 11,625t
Lateral live load = 3090t
People = 110,000 x 200 lb = 11,000t
Snow (20 lb/sf) load = 20lb/sf * 62,500 sf (~roof area) = 625t
Wind (90mph, 25lb/sf) load = 25lb/sf * 1,093ft (longest length) * 226ft (height) = 3,090t
Dead load of the stadium is 45, 000t as the calculation shows. In order to resist this dead load of the structure, the stadium was placed on what is called a plinth, which is the lower square slab at the base of a column.
The live load was calculated as 11, 625t for the vertical such as snow and 3090t for lateral, such as wind.

11. STRUCTURE – BUILDING LOADS
TOTAL LOADS
0.906 t/sf of load on the foundation
Total vertical load = 56,625t
Total surface area = 62,500 sf
So, the structure must resist a total of 56,625t of vertical load.
This diagram illustrates how the loads are split between steel and transferred downward. The red points indicate the transfer connections where load impact is applied the most.

12. STRUCTURE – WELDING DETAILS
This diagram shows how the secondary (grey) members had to be welded on two sides of primary (white) members. The steel envelope is constructed of 22.5 miles of steel.

13. STRUCTURE MODEL Scale: 1:1500 material: artistic wire(craft wire)
Process: the central oval was first made, then the 24 columns are fix in the cardboard and then attatched to the central oval while in reality, the 24 columns are put first and the steel on the top are put by cranes later
STRUCTURE MODEL
as is mentioned earlier each column makes two tangent lines to the central oval something i got from the process was the strength of the whole structure had increased tremendously as i was adding the tangent lines, for the wire i used was very bendable, if i apply pressure to the centre, it is steady, which reflected the strength of this design according to the process in reality, every piece was added seperatly by the crane in the air and welded, an accuracy of the real construction is also reflected

14. REFERENCE
Beijing National Stadium. National Geographic, Youtube. 8 Apr Web. 5 Dec
Mickute, Monika, Sam Pomager, and Lemond Brown. "Form and Function." Beijing National Stadium. N.p., 06 Oct Web. 05 Dec
"Beijing National Stadium, 'The Bird's Nest'" Design Build Network. N.p., n.d. Web. 05 Dec
M=Nestorovie, Miodrage, Aleksandar Cucakovie, Biljana Jovie, and Natasa Teofilovie. "ANALYSIS GEOMETRY STRUCTURE OF FOUR BUILDINGS IN OLYMPIC BEIJING." (n.d.): Web.