Steel Structure Space Frame

 

　　Steel structure space frames are currently a commonly used roofing form for large-scale domestic stadiums, industrial plants, theaters, waiting halls, and other buildings. This new style of structural method relies on the bearing capacity of the steel itself, connecting steel columns one by one with bolted spheres, crisscrossing to support and forming a net-like structure into various shapes of roof spaces. From small meeting rooms of a few meters to large industrial plants with spans of hundreds of meters, these are all suitable ranges for space frame structures.

 

　　1. Steel structure space frames have a free and expansive form. It encompasses both the rhythmic beauty of classical architecture and the romanticism of modern sculptural art. Therefore, more and more architects are using its strength and artistry to design and construct large roof frameworks. This novel and aesthetically pleasing space frame structure has created a new image for modern architecture.

 

　　2. Steel structure space frames are a type of multiple hyperstatic space structure. It is precisely because of the multiple hyperstatic characteristics of the structure and its unique flexibility in shaping compared to other structures. Structural internal force calculations usually use the matrix displacement method. The matrix order depends on the engineering situation. For simple projects, the matrix order can reach tens of thousands. For more complex projects, the matrix order is difficult to calculate. Even using a computer with the Gauss-Seidel method, a single calculation takes hours. Because the workload of structural internal force calculation is large and the construction drawing design is difficult, before the computer-aided design level is completed, it greatly limits the promotion and use of space frame structures.

 

　　The application of steel structure space frames in many large venues today is, from an architectural perspective, a revolution in building structure and materials. From the artistic perspective of building objects, the diverse modeling changes of space frame structures add artistry to the production and living spaces of the people. Space frame structures also have advantages such as light construction materials and convenient installation. At the same time, because the building materials are combined in force, it also has the unique effect of good seismic performance.

 

　　Steel space frames are a unique flower in the modern architectural science garden. In the past ten years or so, it has been widely applied and promoted in our country. Looking around, this bright urban landscape is extending to a wider area.

 

　　Characteristics of Space Frame Structures:

 

　　1. A space frame is a net-like structure composed of many bar frames. It is a highly hyperstatic space structure. Space frames can be divided into flat space frames and curved surface space frames.

 

　　2. Flat space frames are more commonly used, and their advantages are: spatial force system, members mainly bear axial forces, reasonable force, material saving, good overall performance, high stiffness, good seismic performance. Fewer types of members, suitable for industrial production.

 

　　3. Flat space frames can be divided into two categories: cross-truss systems and corner cone systems. The corner cone system has more reasonable force and greater stiffness.

 

　　4. The ratio of the height to the short span of the space frame is generally about 1/15. The space frame members generally use steel pipes, and the nodes generally use spherical nodes.

 

　　I. Arch Structures:

 

　　(1). Force Characteristics and Application Scope of Arches:

 

　　1. An arch is a structure with thrust, and its main internal force is axial pressure. Large-span arch structures can be built using concrete with good compressive performance.

 

　　2. Because the arch structure is reasonably stressed, it is widely used in buildings and bridges. Suitable for stadiums, exhibition halls, etc.

 

　　(2) Types of Arches: Arches can be divided into three-hinged arches, two-hinged arches, and fixed arches, with the latter two being more commonly used.

 

　　(II) Suspension Structures

 

　　(1) Suspension structures are one of the more ideal forms of large-span structures and are widely used in bridges. The main load-bearing components of suspension structures are tensile steel cables, which are made of high-strength steel strands or steel wire ropes.

 

　　(2) The tension of the cable depends on the sag at mid-span; the smaller the sag, the greater the tension. The sag of the cable is generally 1/30 of the span.

 

　　(III) Thin-Walled Space Structures

 

　　(1) Also known as shell structures. It belongs to a spatial force structure, mainly bearing axial pressure within the curved surface, and the bending moment is small.

 

　　(2) Thin shells are often used in large-span roof structures, such as exhibition halls, clubs, and aircraft hangars. Thin shell structures mostly use cast-in-place reinforced concrete, which requires more formwork and labor.