presentation gives data on "how Modeling procedure and Case study of ‘Gocheok Sky Dome’ was done" and how mathematics and finite elemental analysis are useful for as a part of analysis of stresses strain,wind loading..ect.
Modeling procedure and Case study of ‘Gocheok Sky Dome’
1. 1
MODELING PROCEDURE AND CASE STUDY OF
‘GOCHEOK SKY DOME’
Presented by:
LAKAVATH CHANDRASHEKHAR
p16st016@amd.svnit.ac.in
Applied Mechanics Department
Sardar Vallabhbhai National Institute of Technology, Surat,
Gujarat, India.
2. Content
• Over view of Dome
• Modeling
• Various Elements and its properties
• Various steps of Construction
• conclusion
4. Overview of
Dome
Project : South-Western Dome Baseball Stadium, 2009
Location : Seoul, Korea
Occupancy : Sport Stadium
Area : 62,443 ㎡ (2 Story Below Ground, 4 Stories Above
Ground)
Seating capacity : 22,258 Seats
Structure System : Steel Space Frame & RC Frame
Architect : Ilkun + Atee Architects
Contractor : Hyundai Development Company
Time for construction: 6 years
Type of Dome: geodesic Dome
Contents: ballpark, swimming pool, gym
Structure : R.C Frame, P.C Stand Roof/Space Frame +
Membrane, including baseball Hall.
5. Modeling of special structure
Special structure : Based on how the External load resisted
• Compression structure : shells
• Tension structure: tension fabric, air-supported, air inflated and
cable-net
• Both Tension and compression :space grids and diferrent domes
• Am focusing on Tension structure in this ppt presentation
6. Membrane Details
• Surface determines: the distribution and
magnitude of the stress and deflection
under external loading condition.(r is
minimum for out plane stresses)
• Model prepared and tested by frei otto’s
soap film experiment to find the minimal
surface. Or nonlinear analysis
• Finite analysis method: Boundary
conditions of the structure. Newton-
raphson method,cst method.
• Warp yarns in hanging direction of
surface
• Weft yarns (wind load suction resistance)
7. • membrane dome comprises 16 panels with (width=7.4 m)
Resulting in a total size of 100 m by 120 m and a maximum height of 12 m at the
center
• An initial uniform force per width of 3 kN is applied for both warp and fill
directions of the membrane. The prestressing force of the cable varies depending
on the length of the panel from 140 kN for the shortest panel (panel 2) to 170 kN
for the longest panel (panel 8).
• For accuracy welded seams also follows the curve-path
• Fabric waves directions are affected by the patterning & also depends on pre-stressing.
• Equilibrium of geometric and elastic matrixes are used for nonlinear stress deformation
analysis
8. Barrel vault-shaped membrane structure supported by
steel structure
• Shortest panel-2 of Membrane of 58m long,3m high on center,
load is 140KN/cable
• Longest panel-8 of Membrane 100m length and height 12m,
load is 170KN/cable
Uplift pressure :-141 kgf/m2
Downward pressure :79kgf/m2
Snow load:50kgf/m2.
Critical combination of loadingCase Loading direction Load combination
Case1 Downward loading Self weight + prestress + snow + wind
(downwards)
Case2 Uplift loading Self weight +prestress + wing (uplift)
10. Fabric material properties
The fabric used is Sheerfill II,
Ultimate strength : 137.5 kN/m in the warp
direction
In the fill direction: 98.1 kN/m
The coated fabric weight:1.428 Kg/m3,
Thickness:0.76mm,
Solar transmission12%,
Solar reflectance:73%
13. Stress- Deformation Analysis
This Test is Performed to examine the quality of form finding analysis (boundary condition satisfied) i.e for
isotropic pressure minimum surface area is required then displacement should be zero or if boundary condition
doesn't allow for minimum surface then anisotropic and varying prestress values are generated pressure
26. Conclusion
• How the implementation of Prestressing cable can
strengthen the membrane structure (uplift case)
• Regular geometry helps to have more stable response under
loading condition
• How form-finding steps have significant effect on
increasing stiffness of structure
• How Arch's provided at crown area of dome for safer load
distribution to Meridional ribs through lantern ring.
27. What I learned from this work is
• Applications of mathematics in structural engineering field such as by
Non-linear analysis (Newton Ramphson method, Gauss seidal
method, linear lagrangian interpolation function, constant Strain
Triagle method)
• Frei Otto’s technic for finding unlimited beautiful structures
• Fabric used was sheerfill II for light transparent purpose
• Why they introduced Prestressing and when it plays role