STRUCTURAL DESIGN FINAL PROJECT REPORT Valentjn BATLLE | Paola - - PowerPoint PPT Presentation

▶
structural design
SMART_READER_LITE
LIVE PREVIEW

STRUCTURAL DESIGN FINAL PROJECT REPORT Valentjn BATLLE | Paola - - PowerPoint PPT Presentation

Oct 12, 2023 432 likes •771 views

COLE NATIONALE DES PONTS ET CHAUSSES STRUCTURAL DESIGN FINAL PROJECT REPORT Valentjn BATLLE | Paola TORRES | Aurlien DE BOIS TABLE OF CONTENTS STRUCTURAL DESIGN Project presentatjon 01 02 Primary assumptjons Loads defjnitjon 03

slide-1
SLIDE 1

ÉCOLE NATIONALE DES PONTS ET CHAUSSÉES

FINAL PROJECT REPORT

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

slide-2
SLIDE 2

TABLE OF CONTENTS

Project presentatjon Primary assumptjons

02 01

Loads defjnitjon

03

First statjc diagram

04

Secondary statjc diagram

05

2D numerical model

06

3D numerical model

07

3D linear analysis

08

3D non-linear analysis

09

Summary fjgures

10

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

slide-3
SLIDE 3

PROJECT PRESENTATION

The project consists in designing a cover for an archeological excavatjon area. The structure must be supported only by its edges. The structure would be used to observe the excavatjons and provide shelter for visitors. Site Constraints Minimal width of walkways : lmin = 1,5 m Minimal total length of walways: Lmin ≥ 150 m At least three entrances : N, O, SE A minimal height under the structure is imposed : :

  • hmin = 5 m

for R > 15 m

  • hmin = 8 m

for 5 m < R < 15 m

  • hmin = 10 m for

R < 5 m

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

slide-4
SLIDE 4

Materials used in this project are steel and polycarbonate. The structural elements are made out of steel while the cover would be made

  • f polycarbonate. All elements of this design shall be calculated according to Eurocode 3.

Posts | Beams | Structural Bracing Yield strength Re0.2 = 255 MPa Reductjon factor γa = 1.0 Elastjc Modulus E = 210 GPa Specifjc weigth ρ = 7850 kg/m3 Tie rods Yield strength Re0.2 = 1500 MPa Reductjon factor γa = 1.2 Specifjc weigth E = 190 GPa

PROJECT PRESENTATION

Materials

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

slide-5
SLIDE 5

PRIMARY ASSUMPTIONS

Cross Sectjon

Sc: 1/1000

Elevation

Sc: 1/1000

Static Diagram Floor plan

Sc: 1/1000e

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

slide-6
SLIDE 6

PRIMARY ASSUMPTIONS

Floor Plan

Sc: 1/500

Roof Plan

Sc: 1/500

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

slide-7
SLIDE 7

PRIMARY ASSUMPTIONS

Structural axonometry

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

slide-8
SLIDE 8

LOADS DEFINITION

Load types considered Permanent load : G Operatjng loads : Q Climatjc actjon : N (Snow) Climatjc actjon : V (Wind) 1 2 3 4

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

slide-9
SLIDE 9

LOADS DEFINITION

Load combinatjons ULS Load combinatjons SLS 1.35 G + 1.5 Q + 0.75 N 1.35 G + 1.5 Q’ + 1.35 V G + 1.5 V G + Q + 0.5N G + Q’+ 0.5N

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

1 2 3 4 5

slide-10
SLIDE 10

FIRST STATIC DIAGRAM

Shifu and stress analysis Shear and moment diagram under horizontal load

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

slide-11
SLIDE 11

Statjc diagram with a tractjon ring

SECONDARY STATIC DIAGRAM

Shear and moment diagram under vertjcal load

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

slide-12
SLIDE 12

Shear and moment diagram | Load combinatjon 1 Results

2D NUMERICAL MODEL

1 2 3 4 Modeled elements Posts | HEB 300 Beam| HEB 300 Walkway | IPE 160 Tractjon ring| Support

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

slide-13
SLIDE 13

1

3D NUMERICAL MODEL

First 3D model Shear and moment diagram | Load combinatjon 1 2 3 4 Modeled elements

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

1 2 3 4 Posts | HEB 300 Beam| HEB 300 Walkway | IPE 160 Tractjon ring| Support

slide-14
SLIDE 14

3D NUMERICAL MODEL

Walkways 1 2 3 Cross sectjons & necessary checks Beams | IPE 160 Secondary Beams | IPE 80 Natural frequency 4 Shear resistance Vertjcal shifu 5

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

slide-15
SLIDE 15

Posts and beams

3D NUMERICAL MODEL

1 2 3 4 Cross sectjons & necessary checks Posts | HEB 300 Beams| HEB 300 Bending resistancee Shear resistance 5 6 Vertjcal shifu Buckling analysis

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

slide-16
SLIDE 16

Tie rods

3D NUMERICAL MODEL

Cross sectjons & necessary checks 1 2 Tie rods | Ø 2 cm Tractjon resistance

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

slide-17
SLIDE 17

Anneaux primaires

3D NUMERICAL MODEL

Cross sectjons & necessary checks 1 2 3 Compression ring | Ø 68 cm Tractjon ring | Ø 20 cm Normal stress resistance

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

4 Buckling resistance

slide-18
SLIDE 18

Secondary rings

3D NUMERICAL MODEL

Cross sectjons & necessary checks 1 2 Secondary rings | Ø 50 cm Normal stress resistance

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

slide-19
SLIDE 19

Structural bracing

3D NUMERICAL MODEL

Cross sectjons & necessary checks 1 2 Structural bracing | Ø 0.5 cm Normal stress resistance

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

slide-20
SLIDE 20

Load cases analysis ULS 1 : 1.35 G + 1.5 Q + 0.75 N

LINEAR ANALYSIS

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

Min Max Moment [kN.m]

slide-21
SLIDE 21

Load cases analysis ULS 3 : 1 G + 1.5 V

LINEAR ANALYSIS

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

Min Max Moment [kN.m]

slide-22
SLIDE 22

Normal stress diagram

LINEAR ANALYSIS

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

Moment stress diagram ULS 1 : 1.35 G + 1.5 Q + 0.75 N 1 Transfer of thrust forces from the beams to the tractjon ring and the compression ring 2 Bending transmitued by the compression ring at the center of the structure

slide-23
SLIDE 23

LINEAR ANALYSIS

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

Normal stress diagram Moment stress diagram ULS 3 : 1G + 1.5 V 1 Partjcipatjon of secondary elements ; structural bracings & secondary rings 2 Asymmetrical moment, shear and normal diagrams

slide-24
SLIDE 24

Non-secondary role of the secondary rings

LINEAR ANALYSIS

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

1 2 3 Tractjon stress : 270 kN Compression stress : -270 kN Buckling analysis 4 Necessary increase of dimensions elements

slide-25
SLIDE 25

Untensioned cables

LINEAR ANALYSIS

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

1 2 Untensioned cables in assymetrical load cases Necessity of pre-stressing cables

slide-26
SLIDE 26

Structural bracing and structure response

LINEAR ANALYSIS

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

1 2 3 Difgerentjated prestressing to minimize secondary forces Lateral bracing replaced by beams due to too secondary forces when prestrained Ɛ = 10 mm.m-1 & Ɛ = 20 mm.m-1 1 Difgerentjated prestressing to minimize secondary forces 4 Compression stress transmited to the tractjon ring

slide-27
SLIDE 27

Problems of compression stress in the tractjon ring

LINEAR ANALYSIS

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

1 Compression stress due to assymetrical load and prestrain of structural bracing 2 Necessity to prestrain the traction ring

slide-28
SLIDE 28

Tractjon ring prestressing by tjltjng the posts

LINEAR ANALYSIS

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

1 Self-prestressing of the tractjon ring mechanically diffjcult 2 Traction stress in the traction ring due to the beam thrust forces being less transmited to the posts

slide-29
SLIDE 29

Buckling analysis

NON LINEAR ANALYSIS

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

1 Buckling mode in the fjrst confjguratjon of bracings 2 Buckling coeffjcient α = 2.5 Necessity to rethink the structural bracings 1 Buckling mode in the second confjguratjon of bracings with a middle set of bracings 2 Buckling coeffjcient α = 12

slide-30
SLIDE 30

Vertjcal shifu and structure’s natural frequency

NON LINEAR ANALYSIS

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

1 2 3 First structural height h = 10m Walkways’ vertical shift δ = -0.07 m > L/500 Natural frequency f = 3.5 hz

slide-31
SLIDE 31

Étude de la fmèche

NON LINEAR ANALYSIS

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

1 By increasing the structural height, thrust forces are more transmitued to the posts thus reducing the vertjcal shifu 2 The formula f = 18/√(vertical shift) shows that reducing the vertical shift also increases the natural frequency of walkways

slide-32
SLIDE 32

FINAL OPTIMIZATION

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN

1 2 3 Bracing tractjon resistance too low due to too much prestraining Optimization of different elements

  • f the structure (bracings, beams

and posts tilting) to increase cable resistance and maintaning the absence

  • f compression stress in the traction

ring. Beams : HEB 500 to increase the effects of beams tilting by increasing permanent loads 4 Bracing cables : Necessity of high resistance steel ropes (3000 MPA) From Ø 0.5cm to Ø 0.9 cm

slide-33
SLIDE 33

Support reactjon| SLU Structural work rate Vertjcal shifu Structural weight 463 kN per posts Beams | Bending : 57% | Buckling : 34% Compression Ring| Compression : 10% Tractjon Ring | Traction : 50% Tie cables | Traction : 13% Roof bracings | Traction : 95% Lateral bracings | Bending : 17% Contreventement| Buckling : 33% Beams fmax/ fauthorized = 0.16 Walkways fmax/ fauthorized = 0.8 W = 156 T A = 1963 m2 W = 0.79 kN/m2 1 1 2 3 4 5 6 1 2 2 3 4

SUMMARY FIGURES

Valentjn BATLLE | Paola TORRES | Aurélien DE BOIS

STRUCTURAL DESIGN