INFORMATION ON STRUCTURAL SYSTEMS

1. Part 02. Structural System
- Section Active -
Dr. Ho-Kyung Kim
Structural Design Laboratory (SDL)
Dept. of Civil and Environmental Engineering
Seoul National University
Planning of Structural System (M1586.002400)

2. Structural Design Laboratory (SDL) 1
▶Beams are straight-line, bending-resistant structural elements that cannot only resist forces that act in the
direction of their axis, but by means of sectional stresses can receive also forces perpendicular to their axis and
transport them laterally along their axis to the ends. Beams are basic elements of section-active structure
systems.
▶Because of its capacity to laterally transfer loads and still maintain the horizontal space enclosure that is so
convenient for the three-dimensional space seizure, the beam is the structure element most frequently used in
building construction.
▶The bearing mechanism of section-active structure systems consists of the combined action of compressive
and tensile stresses within the beam section in conjunction with shear stresses: bending resistance. Due to
bending deflection an internal rotation moment is activated that counterbalances the external rotation moment.
▶Section-active structure systems can be live expression of the struggle for equilibrium between internal and
external rotation moments.
▶As continuous beam, hinged frame, complete frame, multi-panel frame, and multi-story frame the section-active
structures have brought to full expression the mechanics of continuity. By means of these systems it is possible
to achieve long spans and provide free floor space unencumbered by supports, without having to give up the
advantage of rectangular geometry.
DEFINITION OF SECTION-ACTIVE STRUCTURAL SYSTEM

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▶System of redirecting forces
DEFINITION OF SECTION-ACTIVE STRUCTURE SYSTEMS

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MECHANISM OF BENDING AND BENDING RESISTANCE

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RELATIONSHIP BETWEEN SHEAR, TENSION AND COMPRESSION IN BENDING

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LINES OF PRINCIPAL DIRECTIONS OF STRESS = ISOSTATICS

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STRESS DISTRIBUTION IN BEAM WITH RECTANGULAR SECTION

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SECTION DESIGN OF SOLID WEB BEAMS (1/2)

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SECTION DESIGN OF SOLID WEB BEAMS (2/2)

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INFLUENCE OF CANTILEVER ACTION ON BEAM EFFICIENCY

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INFLUENCE OF SUPPORT CONDITIONS ON BEAM EFFICIENCY

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COMPARISON BETWEEN DISCONTINUOUS AND CONTINUOUS BEAMS

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INFLUENCE OF CONTINUITY ON BEARING MECHANISM

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BENDING MECHANISM IN CONTINUOUS BEAM OVER 5 SPANS

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POSSIBILITY OF EQUAL DISTRIBUTION OF BENDING IN CONTINUOUS BEAM

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BEAM LAYOUTS FOR LOAD TRANSMISSION (1/2)

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BEAM LAYOUTS FOR LOAD TRANSMISSION (2/2)

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STRUCTURE SYSTEMS AND DESIGN POSSIBILITIES FOR BEAM OVER FIVE SPANS (1/5)

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STRUCTURE SYSTEMS AND DESIGN POSSIBILITIES FOR BEAM OVER FIVE SPANS (2/5)

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STRUCTURE SYSTEMS AND DESIGN POSSIBILITIES FOR BEAM OVER FIVE SPANS (3/5)

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STRUCTURE SYSTEMS AND DESIGN POSSIBILITIES FOR BEAM OVER FIVE SPANS (4/5)

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STRUCTURE SYSTEMS AND DESIGN POSSIBILITIES FOR BEAM OVER FIVE SPANS (5/5)

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MECHANISM OF FRAME AND ITS RELATIONSHIP TO THE BEAM WITH CANTILEVERS

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MECHANISM OF RESISTING LATERAL FORCES

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INFLUENCE OF FRAME STIFFNESS ON STRESS DISTRIBUTION AND STRUCTURE FORM
Beam Two-hinge frame Three-hinge frame

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HORIZONTAL AND VERTICAL STRUCTURE SYSTEMS COMPOSED OF HINGED FRAMES (1/3)

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HORIZONTAL AND VERTICAL STRUCTURE SYSTEMS COMPOSED OF HINGED FRAMES (2/3)

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HORIZONTAL AND VERTICAL STRUCTURE SYSTEMS COMPOSED OF HINGED FRAMES (3/3)

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MECHANISM OF THE REVERSE AND DOUBLED FORM OF TWO-HINGED FRAME (1/2)

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MECHANISM OF THE REVERSE AND DOUBLED FORM OF TWO-HINGED FRAME (2/2)

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MECHANISM OF THE REVERSE AND DOUBLED FORM OF THREE-HINGED FRAME (1/2)

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MECHANISM OF THE REVERSE AND DOUBLED FORM OF THREE-HINGED FRAME (2/2)

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VERTICAL STRUCTURE SYSTEMS COMPOSED OF FRAMES WITH DOUBLE-UP COLUMNS

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DESIGN POSSIBILITIES WITH HINGED FRAME SYSTEMS (1/3)

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DESIGN POSSIBILITIES WITH HINGED FRAME SYSTEMS (2/3)

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DESIGN POSSIBILITIES WITH HINGED FRAME SYSTEMS (3/3)

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MECHANISM OF COMPLETE FRAME AND MULTI-PANEL FRAME (1/2)

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MECHANISM OF COMPLETE FRAME AND MULTI-PANEL FRAME (2/2)

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RELATIONSHIP BETWEEN PANEL DESIGN AND MECHANISM OF MULTI-PANEL FRAME (1/2)

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RELATIONSHIP BETWEEN PANEL DESIGN AND MECHANISM OF MULTI-PANEL FRAME (2/2)

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LONG-SPAN STRUCTURE SYSTEMS COMPOSED OF MULTI-PANEL FRAMES (1/3)

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LONG-SPAN STRUCTURE SYSTEMS COMPOSED OF MULTI-PANEL FRAMES (2/3)

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LONG-SPAN STRUCTURE SYSTEMS COMPOSED OF MULTI-PANEL FRAMES (3/3)

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▶Concentric grid from multi-panel frames
BIAXIAL SYSTEMS OF MULTI-PANEL STOREY FRAMES

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▶Concentric grid from multi-panel frames
BIAXIAL SYSTEMS OF MULTI-PANEL STOREY FRAMES (1/2)

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BIAXIAL SYSTEMS OF MULTI-PANEL STOREY FRAMES (2/2)
▶Two-way stacking of multi-panel full frames

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▶Multi-panel frame continuous through all floors
MULTI-STORY STRUCTURE SYSTEMS COMPOSED OF MULTI-PANEL FRAMES (1/3)

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▶Single-story multi-panel frame as support for each two floors
MULTI-STORY STRUCTURE SYSTEMS COMPOSED OF MULTI-PANEL FRAMES (2/3)

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▶Single story multi-panel frame as support for each three floors
MULTI-STORY STRUCTURE SYSTEMS COMPOSED OF MULTI-PANEL FRAMES (3/3)

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▶Biaxial load dispersal
RELATIONSHIP BETWEEN SIMPLE PARALLEL BEAM AND BEAM GRID

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INFLUENCE OF SIDE PROPORTIONS UPON MAGNITUDE OF BIAXIAL LOAD DISPERSAL

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BIAXIAL LOAD DISPERSAL OF BEAM GRID WITH RIGID CONNECTIONS

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BEHAVIOR OF COMPONENT AS CONTINUOUS BEAM ON FLEXIBLE SUPPORTS

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ADDITIONAL BEARING ACTION THROUGH RESISTANCE AGAINST TWISTING

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BEAM GRIDS FOR FLOOR PLANS WITH UNEQUAL SIDES

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DIAGONAL SQUARE GRID

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▶Aside from the fundamental commitment to the configuration of floor plan and to the disposition of supports the
design of beam grids is concerned with three form decisions 1) Geometry of beam pattern 2) Grid relationship to
lateral space enclosure 3) Consistency of beam grid structure. Accordingly beam grids will be classified and
identified as:
▶1. Standard geometries of beam grids
CONSTITUENT CONCERNS IN THE DESIGN OF BEAM GRIDS (1/2)

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▶2. Grid relationship to the lateral space enclosures
▶3. Consistency of beam grid structure
CONSTITUENT CONCERNS IN THE DESIGN OF BEAM GRIDS (2/2)

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SOLID WEB BEAM GRID SYSTEMS (1/6)

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SOLID WEB BEAM GRID SYSTEMS (2/6)

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SOLID WEB BEAM GRID SYSTEMS (3/6)

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SOLID WEB BEAM GRID SYSTEMS (4/6)

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SOLID WEB BEAM GRID SYSTEMS (5/6)

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SOLID WEB BEAM GRID SYSTEMS (6/6)

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BEARING MECHANICS OF THE SIMPLY SUPPORTED SLAB (1/2)

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BEARING MECHANICS OF THE SIMPLY SUPPORTED SLAB (2/2)

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STRUCTURAL SLAB SYSTEMS: LOAD TRANSFER AND OPTIMIZATION FORMS (1/2)

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STRUCTURAL SLAB SYSTEMS: LOAD TRANSFER AND OPTIMIZATION FORMS (2/2)

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EXAMPLE OF STRUCTURAL SLAB SYSTEMS (1/3)

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EXAMPLE OF STRUCTURAL SLAB SYSTEMS (2/3)

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EXAMPLE OF STRUCTURAL SLAB SYSTEMS (3/3)

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EXAMPLE OF BOX FRAME SYSTEMS (1/3)

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EXAMPLE OF BOX FRAME SYSTEMS (2/3)

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EXAMPLE OF BOX FRAME SYSTEMS (3/3)