Longtanhe River ViaductPearl River Tower

Hong Kong Convention and Exhibition Center

Team SharkKevin Sonico

Longtanhe River Viaduct, Yichang

Yichang, China Located near the Yangtze

River Major transit port and

distribution center of goods “Economic hub” of

Western Hubei 1,350 mile (2,175 km) G50

Shanghai-Chongqing Expressway runs through Yichang

Longtanhe River Viaduct

Yichang

What is a Viaduct? “Via” meaning “road,”

“ducere” meaning “to lead.” More than three spans Useful for crossing valleys,

rivers, etc. Used when mountain

roads are inadequate for traffic load

The Longtanhe River Viaduct

Tallest pier: 178m

Girder span: 200m

4-lane roadway (two in each direction)

Ties with Germany’s Kochertal as the 5th highest bridge pier in the world

178 m200 m

Balanced Cantilever Design

• Benefits:– Doesn’t include false work, which is

hazardous and expensive on waterways.

– Beneficial in rural areas where transportation of materials is costly

– Longtanhe viaduct turns a day or longer trip through dangerous mountain roads into a five hour trip.

Balanced Cantilever Design cont.

• Methods are currently being investigated on how construction can be optimized for balanced moments on either side of the piers

• End spans must be shorter than interior spans to counteract moments on adjacent spans

Pearl River Tower

Building Specifications

Pearl River Tower

Building Information

Location: No. 15, Zhujiang West Road, Tianhe District, Guangzhou

Site Area: 10,636 m2

Total Gross Floor Area: 216,557m2

Building Height: 309m

Number of Floors: 71 Floors

Parking: Approx. 890

Office Floor InformationTypical Floor Plate: Approx. 2800m2

Gross Ceiling Height: 3.9m

Net Height: 2.7-3.0m

Typical Floor Loading:Office Area 250 kg/m2

Designated load-bearing area 500 kg/m2

Raised Floor Height: 400mm

“Net-zero” Energy Building “…a structure that does not require an increase in the community’s need to produce electricity.” Guangzhou is a highly polluted city Coal power plants projected to continue in growth Wanted a building to be designed that did not use electricity from the power grid Does not consume additional fossil fuels and will have zero emissions (greenhouse gases) Winning Firm: Skidmore, Owings, and Merrill, Chicago (SOM)

“World’s Tallest Green Tower”

3. Reclamation- “Strategies to harvest the energy that would already be resident within the building”

4. Generation- “Generating clean power in an efficient and environmentally responsible manner”

Skidmore, Owings, and Merrill’s Four steps to net-zero energy

1. Reduction- “Finding as many opportunities as possible to reduce the energy consumed.”

2. Absorption- “Focus on strategies designed to take advantage of the natural and passive energy sources”

Reduction• High performance ventilated

double-wall facades on Northern and Southern sides with mechanized blinds

• Triply glazed facades on Eastern and Western sides

• “Chilled radiant ceiling” and “Chilled-beam” system (approximately 14.5° C) delivered in serpentine arrangement fixed to circular ceiling beam, and metal fins on the perimeter reduces area needed for air conditioning (use of a chilled beam system reduces each floor from 4.2m to 3.9m, adding more floor space)

• “Decoupled” ventilation system providing only fresh air cooled by the above system and vented through access floor

• Dehumidification system using heat as an energy source from the double-façade

• Low energy, high efficiency lighting designed at optimum light intervals

Absorption A building integrated

photovoltaic skin (BIPVs) Photovoltaics on the Eastern

and Western facades, as well as on the Western façade shades

Maximizing natural lighting by using a motorized active Venetian shades between double façade controlled by a photocell that controls the solar gain and glare via a building management system (BMS)

“Vertical axis wind turbines designed to take full advantage of the building’s geometry”

Wind Turbines Southern façade of

building “funnels” wind to four 6x6.8m wind tunnels at floors 24 and 48

Vertical wind turbine encased in each tunnel

Funnel design increases speed of wind by 2.5

Tunnels act as “pressure-relief valves” relieving wind pressure on building

Decrease of wind load on structure allows for reduced structural elements to withstand load, saving money on material costs

Photovoltaics• Building “skin” consists of spandrel panels with

built-in photovoltaic panels (Building Integrated Photovoltaics)

• Lower cost than panels with separate mounting devices

• Solar panels placed asymmetrical on building to optimize solar power offered by the sun

Reclamation• “Harvest energy already

resident within the building.”• Using “chilled radiant

ceilings” and “chilled beams” to cool air

• Once energy is added to the building, it can be reused repeatedly

• Example: recirculated air is chilled or heated and added to air from the outdoors before delivered to occupied areas of the building.

Generation• Concept design used “micro

turbines” for the building to produce power in an environmentally responsible manner

• Fuel source for micro turbines includes natural gas, hydrogen, propane, and diesel

• On-site power generation eliminates need of power delivered by grid (delivered power is less than 30-35% efficient)

• 50 micro turbines were originally designed to be daisy-chained together to operate at an efficiency of over 80%

Structural Elements• Structural design by Skidmore, Owings, and Merrill (Chicago)• Lateral load resistance: Interior reinforced concrete core and

series of mega columns linked together by six story steel X braces on the narrow edge facades of the building

• Perimeter columns and mega columns linked together by two-story outriggers and belt trusses at the major mechanical levels

• Redundancy and robustness achieved by belt trusses and perimeter moment frames

• Mega columns consist of built up structural steel I-sections encased in concrete

• Structural design components divided into thirds of the building

The Kicker…The Pearl River Tower is owned by China National Tobacco’s Guangdong Tobacco Company

Overview

Overview

Lessons Learned

• Building did not meet “net-zero” requirements, but consumes 58% less energy than the baseline model

• Use of new “energy efficient” technologies was limited, i.e. the power company would not buy surplus electricity from the Pearl River Tower

• Chinese authorities reluctant to import technologies from other parts of the world

• Required by China, Skidmore, Owings, and Merrill worked alongside the Guangzhou Design Institute

The Hong Kong Convention and Exhibition Center

Three Construction Phases• Phase I—Built in 1988 as

the “original” Hong Kong Convention and Exhibition Center (HKCEC)

• Phase II—Floating island convention center, built from 1994-1997

• Expansion—Trusswork expansion from the original building to the floating island built from 2006-2009

Expansion

Phase II

Phase I

Phase I• Constructed in 1988 on

“reclaimed land.”• Built over area of 1.7

million ft2• Owned by the Hong Kong

Trade Development Council (TDC)

• Used as a convention center to promote domestic and international business in China

Phase II

• Before any building design, a designated site was examined to determine a “floating island” construction of phase II

• 31.6 million ft3 of sand was used with gravel and battered rock walls to support the structure

Phase II (cont.)• Designed in conjunction

with Skidmore, Owings, and Merrill (SOM)

• “Top—down” unconventional approach to building phase II broke several records in Hong Kong’s building history and won industry accolades

• Roof is a 40,000m2 aluminum cladding for intended shape

• Feng Shui?

Phase II Completed• Atrium sky bridge in back connects

original building to addition• New structure allows direct access for

boats with imports

•Structure finished on July 1, 1997, when Hong Kong was returned back to China after more than a century of British rule•SOM: “We aimed for something symbolic that marked this significant point in time.”.”

HKCEC Expansion

Expansion proposed in 2006 to replace existing atrium with three floors of convention center

Expansion would be placed directly over 330-ft-wide water channel

Provide 19,200m2 more exhibition space

Project Goal: “Hong Kong’s existing mega fairs can become number one in the world.”

HKCEC Expansion (cont.)

• Mega truss work used to suspend new exhibition space in place

Green Initiatives

FactsSquare meters

Total Gross Area 306,000

Total Site Area 92,400

Rentable Space 91,500

Purpose-built Exhibition Hall Space 66,000

Six (6) Exhibition Halls 66,000

Two (2) Theatres (with seating for 336 and 367)

800

Fifty-two (52) Meeting Rooms 6,000

Other Multi-functional Rental Space

13,000

Seven (7) Restaurants Total seating for 1,340

Two (2) Underground Car Parks Over 700 parking bays

Skidmore, Owings, and Merrill are leaders in

modern and innovative structural engineering

ReferencesLongtanhe River Viaduct• http://www.highestbridges.com/wiki/index.php?title=Longtanhe_River_Viaduct

Pearl River Tower• Frechette, Roger E. III, P.E., Gilchrist, Russell, LEED AP, Skidmore, Owings, and

Merrill Seeking Zero Energy, ASCE magazine, January, 2009• http://archrecord.construction.com/features/archives/0612casestudy-1.asp• http://www.energydesignresources.com/resources/e-news/e-news-69-chilled-

beams.aspx• http://pearlrivertower.com

Hong Kong Convention and Exhibition Center• http://HKCEC.com• http://www.scifire.com.au/images/hkcec_02.jpg• http://info.hktdc.com/CECexpansion/