Advantages of bolted ball nodes

 As welding technology encounters the twin challenges of curved space surfaces and oversized spans, the bolted ball node, with its unique structural intelligence, is reshaping the engineering logic of modern steel buildings.

I. the welding technology of the space dilemma

 
The rigid yoke of geometric constraints

In the construction of a shaped roof of an art museum, the complex intersection of double-curvature steel beams made the traditional welding encountered technical bottlenecks. Local deformation caused by heat input so that the 16mm thick plate to produce 0.3mm/mm waviness, even with the segmented welding process, still can not meet the surface accuracy requirements, and ultimately forced to cut and replace 23% of the components.
 
Spatial Conduction of Residual Stress

After welding the 120m span truss of an international exhibition centre, the residual stress triggered an 8cm arching deformation of the overall structure. Although 65% of the stress was removed by vibration aging treatment, the resulting schedule delay led to an economic loss of 1.5 million RMB per day, exposing the systemic risk of welding technology in large-scale structures.
 
 
Dimensional Collapse in Quality Control

In the welding of tubular nodes in a super high-rise building, the porosity defect rate in the elevation welding position reached 12%. Ultrasonic flaw detection showed that there was a 17% blind spot for defect detection in three-dimensional spatial welds. This quality control uncertainty forced engineers to set a 35% strength redundancy, resulting in a waste of 47 kg of steel per square metre.
 

II. Spatial revolution of bolted ball nodes

 
Topology Optimisation for Multi-Directional Force Transmission
The C-column nodes of Beijing Daxing Airport are connected by bolted ball joints, which are balanced in a three-dimensional force system by adjustable bars in 36 directions. Compared to traditional welded nodes, its stress concentration factor is reduced from 2.8 to 1.3, resulting in a 22% reduction in structural steel usage. Each bolt ball is equivalent to a miniature spatial coordinate system, which can accurately adjust the angular deviation of ±1.5°.
 
 

 Xiong'an Station roofing project

Precision leap in cold assembly

In the Xiong'an Station roofing project, 6,800 bolted ball nodes achieved millimetre-level installation precision. The high-strength bolt holes processed by CNC machine tools, together with three-dimensional laser positioning technology, enabled the installation error of the 800mm diameter bolt ball nodes to be controlled within 0.3mm, creating a construction record of lifting 2,400 rods in a single day.
 
 
Lifecycle of Reversible Connections

The removable nature of the bolted ball nodes saved 78% of the dismantling costs during the renovation of the Guangzhou Asian Games venues. By adjusting 20% of the length of the rods and 15% of the angle of the bolt balls, the original structure was successfully converted into an e-sports arena, demonstrating an adaptability that is difficult to achieve with traditional welded structures. This "Architecture Lego" mode has increased the reuse rate of steel structure from 12% to 45% of the welded system.
 

III.Evolutionary Path of Technological Symbiosis

Intelligent Proportioning of Hybrid Nodes

The tensile beam structure of the sports centre adopts welded box beams in the tensile zone to ensure continuity, and uses bolted ball-node mesh shells in the compression zone to achieve freedom of form. This rigid-flexible coupling design reduces structural deflection by 42% and steel consumption by 19%, creating a new paradigm for shaped large-span structures.
 
Accurate Pre-assembling of Digital Twins

During the construction of the dome of the Data Valley in Xiantao, Chongqing, BIM technology discovered the spatial interference problem of the bolted ball nodes 37 days in advance. The connection angles of 186 nodes were optimised through virtual preassembly to avoid on-site rework losses. Compared with the after-the-fact correction of traditional welding, this kind of pre-judgemental control increased the construction efficiency by 2.3 times.

dome of the Data Valley

 
Synergistic evolution of the materials revolution

A Shanghai research centre project used aluminium-magnesium alloy bolt ball nodes with high-strength titanium alloy rods to create a space mesh shell that is 51% lighter than traditional welded steel structures. The application of new self-lubricating bolt sleeve technology increased the rotational stiffness of the nodes by 40%, solving the technical problem of dissimilar metal connections.

The construction log of the basketball arena records such a set of comparative data: the use of bolted ball node programme saves 68 days of work compared with the all-welded structure, reduces the welder's input by 83%, and reduces the testing cost by 79%. Behind this set of figures, reflecting the steel structure connection technology from "flame sculpture" to "precision assembly" paradigm shift. When the welding technology touches the double boundaries of material science and space mechanics, the bolt ball node with discrete, modular structure philosophy, for the steel building to open up a new dimension. This technological iteration is not a simple substitution, but rather a joint expansion of the frontiers of human possibilities for shaping space.