Jiaozuo Tai Chi Culture Exchange Center

Jiaozuo, in Henan province, is the historical heartland of Tai Chi — the birthplace of Chen-style Tai Chi in Chenjiagou, Wenxian, within its territory — and the Tai Chi Culture Exchange Center is built to be more than a venue for the art: it is an architectural embodiment of it. The building’s plan radiates outward in a fan shape, its roof follows a continuous arc with a total length of 423 metres, and its principal structural gesture is a 40-metre fan-shaped cantilever — among the longest of its class in Chinese public architecture.

The structure that makes the gesture possible is a steel spatial pipe truss system, engineered, fabricated and erected by Permanent Steel across an approximate building area of 16,000 m². The system is not hidden behind the architecture; it is the architecture — an exposed network of circular hollow-section members whose geometry carries the Tai Chi vocabulary of circle, flow, balance and boundless movement into the built realm.

This case study examines the engineering of the fan-shaped cantilever, the continuity of the 423 m arc, the reasons a spatial pipe truss is the correct system for a cultural building of this kind, and the architectural-structural dialogue that makes the building’s form its meaning.

A spatial pipe truss is a three-dimensional truss built from circular hollow-section (CHS) members — a lattice of tubes whose interconnecting nodes form a coherent framework in space rather than a collection of planar frames. For this building, the system was chosen for five reasons that matter together:

• Organic geometry: pipe trusses follow curves and non-orthogonal layouts naturally. Members meet at arbitrary angles without the visual noise of gusset plates and rolled sections; the node detail is a clean weld line between round members. This is the only major structural system that could express the fan and the 423 m arc without turning them into a diagram of compromise.
• Efficiency in compression and torsion: the circular hollow section is the most efficient closed shape for compression and torsion — the very actions a curved, cantilevered, three-dimensional truss accumulates. Material goes where the geometry needs it, not where the section shape demands.
• Exposed aesthetics: the roof is an architectural ceiling as much as a structure. CHS members are dimensionally clean, weld-finished and coated to be looked at; the truss is the interior design, and its members are intentionally left visible, expressing the load paths as art.
• Aerodynamics: round members behave more predictably than flat sections under wind, and in a building of this prominence where wind uplift on a sweeping roof is a governing case, that predictability is double value — structural and code-related.
• Continuity of the arc: the three-dimensional lattice distributes the forces of the long continuous arc in all directions, so that the 423 m sweep behaves as one coherent flexible body rather than a chain of disconnected planar frames.

The result is a roof that is simultaneously the building’s icon and its skeleton: the pipe trusses do the entire job of holding up a curved, cantilevered cultural building, and they do it in full view.

If the 40 m fan is the building’s moment of drama, the 423 m arc is its daily reality — a continuous curved structure sweeping around the site, around the program, around the visitor’s experience. Engineering a structure of that length in an unbroken curve is a discipline of its own.

What the arc demands of the structure

• Radial and circumferential action: the curved roof behaves simultaneously as a set of radial trusses (spanning the width of the building) and as a circumferential system (carrying forces around the curve). The pipe truss lattice unifies both roles: radial trusses carry the primary spanning, while the circumferential members and bracing distribute the arc’s longitudinal forces and stabilise the curve against lateral buckling.
• Curved-member fabrication: the circumferential members follow the arc’s geometry — produced either by precision bending of the tubes or by kinked segmentation where the radius demands it, with the geometry written directly from the model into the bending and cutting machines. Every curved piece is a defined part of one continuous body, not an approximation.
• Thermal movement along 423 m: a structure of this length moves with temperature — the arc grows and shrinks between seasons by a total that must go somewhere. Expansion provisions were placed so that the curve’s thermal breathing is accommodated without locking stresses into the truss chords, and the cladding details at those provisions remain weather-tight through the movement.
• Continuity of stability: a long curved structure has its own stability logic: lateral buckling of the curve, the interaction of radial and circumferential thrust, and the behaviour of the free edges along the arc. The three-dimensional lattice is the stability system — no member stabilises itself; the body stabilises the body.

Building the sweep

The arc was erected in a sequence that kept the structure stable at every interim state: blocks erected and connected progressively along the curve, with temporary stabilisation at the leading edge until each circumferential tie was completed. Closure of the arc — bringing the two ends of the sweep to meet — was executed under survey control with the thermal movement of the day accounted, so that the final continuity connection closed a gap of minutes of thermal drift rather than a gap of accumulated error.

The design and delivery followed the Chinese steel structure and actions codes applied through full three-dimensional analysis — the same platform used across Permanent Steel’s long-span portfolio — with the building’s special characteristics checked explicitly:

• Cantilever verification: tip deflection and level were verified by survey after de-propping; long-term deformation behaviour was reviewed against the design envelope with the camber absorbing the initial sag.
• Wind performance: the sweeping roof’s uplift and suction cases were enveloped per the code provisions, with the cantilever’s uplift-critical anchorage verified in the net-upward regime.
• Dynamic serviceability: the roof’s vibration response under crowd and rhythmic loading was assessed against serviceability criteria, with the spatial lattice’s stiffness confirming comfortable performance under normal occupancy.
• Thermal integrity: the 423 m arc’s expansion provisions were verified across the seasonal and diurnal temperature range, protecting the truss chords and the cladding through the sweep’s breathing.

Completed, the centre now serves the culture it was built for — performances, exhibitions, exchanges and daily Tai Chi practice beneath a roof that demonstrates, in steel, the art’s own principles of circle, flow and balance. For the structural engineer, that public service is the final verification: a building whose structure was trusted to be both architecture and physics, and has since proved, in daily use, that it is both.