Keywords: Hall, slab (plate), truss, vault, shell, folded slab, pneumatic construction

CONSTRUCTION SYSTEMS OF HALL BUILDINGS

Hall buildings allow the creation of free spaces with little or no internal support. The characteristic feature of hall buildings is a large ground plan and a relatively small height. Hall objects are used especially for single-storey buildings. Unlike the construction systems of multi-storey buildings, the hall buildings are characterized by a supporting roof structure.

The hall object can also include internal built-in floors with different height requirements:

• Two-storey halls
• Large-scale halls
• Combined monoblocks

The hall buildings are characterized by extremely high variability. The repeatability of the types of indoor buildings is significantly lower compared to multi-storey buildings, they are far more individual objects.

Hall objects are used especially for:

• Cultural purposes (theatres, cinemas, exhibition pavilions, gathering, etc.)
• Sports purposes (multipurpose and sports halls, tribunes and stadiums roofing, swimming pools, etc.)
• Manufacturing and storage purposes (production halls, warehouses, markets, etc.)
• Traffic purposes (station halls, platforms roofing, car and bus garages, service halls and repair shops, docks, etc.)

In most cases, hall objects have a split supporting function and cladding. The load-bearing function transfers static and dynamic loads to the foundation structures. Cladding provides the desired state of the internal environment and consists of roof cladding, curtain wall and substructure.

The design must be solved, depending on their spatial stiffness, in order to capture the horizontal forces in the pushed and drawn systems, to allow for greater deformability of the structure (especially for drawn systems). The interaction of the subsystem and the assembly (packing) structures and the overall stabilization of the roof sheets in the tensile systems is of considerable importance.

From the viewpoint of static stress, hall structures can be divided:

• Bending construction systems
• Compressive construction systems
• Tensile construction systems

BENDING CONSTRUCTION SYSTEMS

The basic element is a bend-loaded, simply inserted or interlocking element that transmits primarily vertical loads. All load on the simply stored element is transmitted by bending stress in the middle of the span. The load capacity then depends on the cross sectional modulus of the beam and the permissible stress of the material. If the beam structure is cantilevered into the support (the structure is rigid), a bending moment is created in the support area, which is also transmitted by the supporting (vertical) structure of the frame system. As a result of the interaction of the supporting structure, the bending moments in the frame are reduced. Since the upper beam of the beam and the frame beam are stressed, stability must be ensured before turning. Structural systems stressed mainly on bending include plate systems, trusses and frame systems.

Plate system

Plate systems, as it is already apparent from the title, are made up of different types of boards (with reinforced ribs, cellars, etc.). They are designed to stretch to 24 meters and element widths up to 3 meters. To ensure stiffness, the boards are interlocked.

A plate structure could be formed of unidirectionally or bidirectionally tensioned structures carrying bending loads in both directions. The system consists of plates from planar or spatial lattice trusses.

Trusses system

Truss system consists mainly of the roof trusses (beam elements) deposited on the columns, beams or walls. Trusses can have different shapes (straight head, rack, saddle, arc etc.), various structural solutions (solid panel, lattice etc.) and various material design (reinforced concrete, steel, wood etc.). The roof trusses are stored within the roof surface elements (ribbed or cassette panels with lightweight slab) or roof purlins carrying the roof cladding.

Frame system

The frame system transfers the frame bending moment to the frame stand as a result of the rigid connection. A disadvantage of bending stress of machinery frame can be partly eliminated by a continuous frame structure design. The course of the bending stress in the structure depends on the bending stiffness of the stand and the riser, and the ramps are also affected. The higher bending moment is then concentrated in places with higher bending stiffness. The frame structure may be in the form of a cantilevered frame, two-hinge or three-hinge frame or cantilever frame. The construction can be solved from concrete (reinforced concrete structures, monolithic or prefabricated), steel (thin-walled or full-body profiles) or wood (solid or lattice, etc.).

COMPRESSIVE CONSTRUCTION SYSTEMS

If the arc shape or flat structure designed in the shape of the load pressure line (resultant line or area), the structure transmits pressure loads. Since the shape of the structure is stable but the load is not necessary, part of the load is transmitted by the bending moment. The design should be designed to convey the prevailing load by its own weight and snow. This creates a parabolic shape of the compressive structure. The static effect of the compressive structure can be achieved by shaping the frame construction so that the frame bending capacity is zero. The support system then transmits the vertical and horizontal responses of the arched (compressive) structure. Compressive construction systems include arc structural system, flat compressive construction system (vaults and shell), rod structural system and folded slab structure system.

Arc structural systems

Arch structural systems have a support system designed for buckling pressure in combination with a bend. The stiffness of the sectional structure prevents buckling in the plane of the arc. Stiffness of the ceiling boards and own flexural rigidity prevents deviation from the plane of the arc. Arcs can be clamped, two-or three-jointed articulated. Most often steel or reinforced concrete is used as a material. The construction itself can be lattice or full-body. Spans these structures may reach 100 m.

Flat compressive construction systems - vaults

The vaults are loaded with buckling pressure and bending. The stresses are transmitted by overvoltage of the cross section due to the prevailing vertical load. The construction result is a massive vault construction and limited ability to transfer point loads. For correct design, it is important to know the shape of the result line from the load by the weight of the structure. The material is used mainly stone or brick. For the proper functioning of the vault, the shape of the resultant line is significant from the load by the weight of the structure itself. The pressure lines must always remain inside the cross section core (in the case of the rectangle in the inner third of the height).

Flat compressive construction systems - shell

The shells have a small structural thickness and the bending loads are transmitted only to a limited extent. The stability of the compressive parts is ensured by using the shape of a double curvature construction or by co-operating with reinforcing ribs and shell faces.

Rod structural system

Rod structural systems have to a certain extent similar effects as a flat construction of the same shape. The principle of a slab or rod structure is an effort to replace the static effect of a flat structure with bars made of reinforced concrete, steel or wood. The cylindrical vault-shaped rod structure acts as a cylindrical shell clamped into rigid front walls.

Folded slab structure system

Folded slab structure is formed from flat triangular elements creating a rigid spatial system. Suitably selecting the shape of folded slab can be achieved by translational or rotational surfaces.

TENSILE CONSTRUCTION SYSTEM

The tensile construction system includes suspension systems, pneumatic systems and suspended systems.

Suspension systems

The suspension systems may be truss, panel, cable and membrane structures. The elements do not have bending stiffness and are arranged in parallel or radially in a single layer or multilayer arrangement. Load transfer occurs through the normal force in the profile and the horizontal component of the supported reaction. This component lifts the support system high above the terrain. This requires its efficient construction design.

Pneumatic systems

Pneumatic systems are carried by overpressure of the internal air. The construction consists of a thin membrane preloaded with internal overpressure. In the case of low-pressure structures, the overpressure in the entire space is 100-300 Pa and is stabilized by large spans in combination with surface stiffening ropes. For high-pressure structures, the air pressure is 0.1-0.5 MPa and is concentrated in the so-called skeleton of the object (ribs, curves). Less sponge up to 25 m are used.

Suspended systems

The principle of the suspended system is the suspension of the roof beam by means of bars anchored to pressed pilots, arcs or frames, etc. It is a multistage system reminiscent of the so-called superstructures in multi-storey buildings. It is a multistage system reminiscent of the so-called supersconstruction in multi-storey buildings. It therefore belongs to efficient roofing systems for large spans (150 m or more).