CITIC TOWER BEIJING: TECHNICAL REVIEW AND SPECIFICATIONS

The CITIC Tower, widely known as "China Zun," stands as the tallest building in Beijing and a masterpiece of structural resilience in a high-seismic zone. Rising 528 meters (1,732 feet) in the heart of the Central Business District (CBD), the tower is the only building in the capital to exceed the 500-meter threshold, dominating the skyline with its distinct waist-narrowing profile.

This technical review analyzes the towers "Zun" inspired geometry, its complex composite mega-frame designed for earthquake resistance, and the advanced vertical transportation technologies utilized during its construction.

ARCHITECTURAL DESIGN AND GEOMETRY

Designed by Kohn Pedersen Fox Associates (KPF) in collaboration with the Beijing Institute of Architectural Design (BIAD), the form of the tower is inspired by the "zun," an ancient Chinese ritual vessel used for holding wine. The building features a taut, curving profile that is wide at the base (78 meters), narrows at the "waist" (54 meters), and flares out again at the top (69 meters).

This concave geometry is not merely aesthetic; it serves a functional structural purpose. The flaring base provides a stable footprint to resist overturning moments, while the widening crown maximizes the lease depth and prime real estate area on the upper floors. The rounded corners of the square plan are aerodynamic, reducing the wind drag coefficient and mitigating vortex shedding, a critical concern for a structure of this height.

STRUCTURAL ENGINEERING AND SEISMIC RESISTANCE

Beijing is located in a high-seismic zone, requiring the CITIC Tower to meet some of the strictest seismic codes in the world for supertall buildings. The structural engineering, led by Arup, employs a "dual system" to ensure stability and redundancy.

The primary system is a composite mega-frame consisting of a massive reinforced concrete core and eight perimeter mega-columns. These mega-columns are "concrete-filled steel tubes" (CFT), which combine the tensile strength of steel with the compressive strength and fire resistance of concrete. The core and perimeter columns are linked by four levels of outrigger trusses and belt trusses, which lock the outer frame to the inner core, forcing them to act as a unified cantilever. This system prevents excessive drift during earthquakes and ensures the tower remains elastic during moderate seismic events.

FOUNDATION AND GEOTECHNICAL SYSTEMS

The tower sits on a massive pile-raft foundation designed to distribute the immense gravity loads of the 108-story structure. The raft is a thick reinforced concrete mat that bridges over a dense cluster of bored friction piles.

These piles extend deep into the multi-layered soil of the Beijing basin to reach stable strata. The foundation design was complicated by the presence of a vast underground transportation network, requiring the basement levels to integrate seamlessly with the CBDs subterranean pedestrian and subway grid.

VERTICAL TRANSPORTATION AND CONSTRUCTION LOGISTICS

The CITIC Tower is serviced by a vertical transportation system supplied by KONE. The building utilizes KONE "UltraRope" technology, a carbon fiber hoisting cable that is significantly lighter than traditional steel ropes. This weight reduction drastically cuts the moving mass of the elevator system, reducing energy consumption and allowing for longer single-shaft travel distances.

During construction, the project utilized the "JumpLift" system. These self-climbing elevators used the permanent shafts while the building was still rising, allowing workers and materials to be transported safely and efficiently in an enclosed environment. This innovation significantly accelerated the construction schedule compared to traditional external hoists.

SUSTAINABILITY (LEED GOLD)

The tower is designed to achieve LEED Gold certification. The façade is a triple-glazed unitized curtain wall system that provides superior thermal insulation. The window-to-wall ratio is optimized to balance natural light penetration with solar heat gain control.

The building employs a sophisticated Building Management System (BMS) that integrates demand-controlled ventilation and LED lighting to minimize energy waste. The concave shape of the tower also directs rainwater into collection systems at the base for recycling and reuse in landscaping.

TECHNICAL DATA SHEET

Official Name: CITIC Tower
Chinese Name: Zhongguo Zun (China Zun)
Location: CBD Core, Chaoyang District, Beijing, China
Architect: Kohn Pedersen Fox (KPF) / TFP Farrells (Concept)
Structural Engineer: Arup
Completion Year: 2018
Architectural Height: 528 meters (1,732 feet)
Floor Count: 108
Elevator Supplier: KONE
Structural System: Composite Mega-Frame with Concrete Core
Primary Function: Office (CITIC Group HQ), Observation

FREQUENTLY ASKED QUESTIONS

Is CITIC Tower the tallest building in China?
No. It is the tallest building in Beijing, but nationally it is surpassed by the Shanghai Tower, Ping An Finance Center, and others.

Why does the building flare at the top?
The widening at the top mimics the mouth of a "zun" wine vessel. Practically, it creates more floor space on the high-value upper levels, offering larger offices and observation decks with premium views.

Can the public go to the top?
Yes, the top floors (105-107) are designated as a sightseeing platform, offering a 360-degree view of the Forbidden City and the greater Beijing metropolitan area.

What is "UltraRope"?
UltraRope is a carbon-fiber-based elevator cable used in the CITIC Tower. It is lighter and stronger than steel, which allows the elevators to travel higher and use less energy.