dnv’s puls buckling code panel ultimate limit state new ... puls... · structural design - ships...

www.dnv.com

Slide 1 20-Apr-04 © Det Norske Veritas

Developed by: DNV Maritime/Section for Hydrodynamics and Structures (mtpno361)Responsible DNV Unit for maintenance/sale: DNV Software

DNV’s PULS buckling code

Panel Ultimate Limit State

New ComputerizedBuckling Code

Non-linear plate theory

www.dnv.com


PULS buckling code- DNV buckling rules and standards

- Why a new buckling code?

- Theoretical foundation

- PULS element library

- PULS features

- Demonstration of programme

- Practical exercise

Presentation overview

www.dnv.com


PULS implementation in the Rules and Standards

1. Offshore standard RP C-201, Part 2 ”BucklingStrength of Plated Structures” 2003

2. Steel Ship Rules, Part 3 Ch.1, (1A1) ”Hull Structural design - Ships with length 100 meters and above”, Sec.13, D Panel Ultimate strength, ESP additional notation

January 2004

3. LAN (Lloyds/ABS/DNV) common scantlings project for tankers.

2004

www.dnv.com


Recommended PracticeDNV-RP-C201

Buckling Strength of Plated StructuresOctober 2002

Part 1:Conventional buckling code

Updated CN30.1

Part 2:PULS (Panel Ultimate Limit State)

Computerized buckling code

Semi-empirical Semi-analytical Non-linear light

PULS in the new Recommended Practice (RP)

www.dnv.com


Recommended Practice RP C-201

• The RP C-201 was released early 2003, and replaces the old Classification Note 30.1 (CN30.1)

• The RP is a supporting document for the DNV Offshore Standards describing two equally acceptable approaches for calculating the buckling capacity of flat plated structures

• The RP contains two separate sections Section one covers updating of the “old” Class Note 30.1 with respect to buckling of plates and girdersSection two covers the new buckling code PULS

• The curved shell part from CN 30.1 has been placed in a separateRP, RP C-202

www.dnv.com


Why a new buckling code?

i) Ship Rule formulas predicts bucklinglimit ..not Ultimate Strength

Modern design principles shall be based on Ultimatestrength/ULS design principles

ULS design principles are the only feasible concept for estimating safety margins against failure

ii) Present Buckling Rules are ”Rule book” solutions – initial scantling assessment

Present Buckling Rules are not consistent for usetowards linear global FE analysis results, combinedloads, bi-axial compression, shear etc. ⇒ final scantling assessment

IACS, DNV, Lloyds, ABS has decided to useUltimate Limit State Principles in newUnified Requirementsand Rules currently up for revision

iii) Time for updating rules and implementmodern ULS design principles usingdirectly recognized buckling and non-linear postbuckling theory

Programming non-linear plate/shell models;

PULS = ”Non-linear light”

Computerized buckling code based on ”Non-linearlight” theory easily implemented into spreadsheets, etc.Designers will mostly use PC tools in design

PULS ”non-linear light” gives immediate results

www.dnv.com


PULS approach : Direct application of recognized non-linear plate theory

“ Non-linear light theories ”

• Buckling and ULS estimates of panels very complex technical issue for combined load situations

• Direct method gives more realistic buckling estimates - Improved safety control

• Buckling Model and Theory Framework “in house”

• Transparent - recognized non-linear text book theory as basis

• More data output – 3D graphics for improved understanding of buckling failure mechanism

Best approach for optimal use of steel per defined target safety

Robust design

Why new buckling code

Improved Safety control

Fast and easy

www.dnv.com


Stiffened panels

a)

b)

Ship Hull

Global Strength

Local Strength

Local strength: PULS is a code for bucklingand ULS assessments

of stiffened panels, girder plates, stringer decks etc.

a)

b)

SHIP HULL STRENGTH SPLIT IN TWO LEVELS:a) GLOBAL

b) LOCAL

PULS: Area of application

www.dnv.com


PULS Buckling code

Panel Ultimate Limit State

Purpose:

- Simplified and user-friendly non-expert analyses tool for load bearingcapacity assessment (ULS) of thin-walled stiffened panels used in ship and offshore constructions

P-ULS design principles for ship structures

Extreme loads Accepts elasticbuckling deflections Do not accept

permanent sets/bucklesin plates

Ensure strongstiffeners

Based on advancedmethods – for non-experts

PULS code principles

www.dnv.com


PULS Buckling code- Assessment of ultimate load bearing capacity of stiffened panels as strengthmeasure. Max load capacity - nonlinear analysis

- Assessment of buckling limit of stiffened panels – to be used in cases whereconstruction elements are not allowed/recommended to buckle elastically: Ensuresmore steel. Buckling limit also relevant for functional requirements (SLS). Linearized analysis (Eigenvalues)

- Consider all types of load combinations (bi-axial, shear, tension/compression and lateral pressure) as consistent with output from linear FE hull/Nauticus models


www.dnv.com


PULS Buckling codeProgramme language:- Fortran 95: All calculations (solving equilibruim equations, incrementation…)

- Visual Basic: User interface

- VB PulsComClasses.dll file for easy plug in different User Interfaces

PULS Stand alone programs: 2 versions – Explorer and ExcelAvailable from DNV Software Web site download/time limited free lisence

(2 versions: Explorer and Excel versions apply same input file for easy use)Nauticus Software:

SectionScantling/differentFE Rule Packages


www.dnv.com


Theoretical Basis- von Karman/ Marguerre’s geometric non-linear plate theory

- Orthotropic plate theory for stiffened panels (S3)

Establish non-linear elastic equilibrium equations - Raleigh-Ritz discretization of deflections (Fourier serie expansion)

- Energy methods, virtual work/stationary potential energy

Solves non-linear elastic equilibrium equations

- Incremental perturbation procedure with arc length control

Solve local stress limit state functions - Check of material yield along plate edges and in internal selected “hot

spot” positions.

Load history - load combinations: bi-axial + shear + lateral pressure

Ultimate strength estimate

Moderate large deflections

Theoretical foundation: Overview

www.dnv.com


Theory and principles

Buckling:

• Linear buckling / Eigenvalue • Postbuckling, nonlinear• Ultimate limit state• Postcollapse

Load

Displacement

ULS

PostcollapsePostbuckling

Yield

Linear theory

Buckling

www.dnv.com



• Deflections represented by trigonometric functions, defined over the entire geometry

- Buckling deflections tend to be periodic- Need very few dof compared to FEM- Any shape can be represented by applying

sufficiently many terms

www.dnv.com



• Principle of stationary potential energy:

• Intuitively: The structure adjusts itself to the shape that requires the least energy

P

P

0TU =δ+δ=Πδ

www.dnv.com



• Large deflection plate theory, membrane strains (von Karman / Marguerre):

• Total strain found by adding the bending strains according to the Love-Kirchoff assumption:

y0xyx0yxxyxy

yy02yyy

xx02xxx

wwwwwwvu

www21v

www21u

,,,,,,,,

,,,,

,,,,

++++=γ

++=ε

++=ε

ijijtotij zw ,−ε=ε

www.dnv.com



Incremental solution procedure:

• Linearization – reduce equation system to 1. order

• Arc-length incrementation

η∂∂

= mnmn

AA&

η∂Λ∂

=Λ&

1-imn

1-imn

imn AAA &η+=

11 −− Λ+Λ=Λ iii &η

Λ&

mnA&

ηΛ

mnA

www.dnv.com



Staging:

• Assume piecewise linear load path

• Number of load parameters reduced to one

)PP(P)(P 1-si

si

1-sii −Λ+=Λ

www.dnv.com


PULS element library: Overview

• U3: Unstiffened plate element

• S3: Stiffened plate element

• T1: Stiffened plate element (non-regular geometry)

www.dnv.com


Typical buckling modes in unstiffened plate

a) Axial compression b) Transverse compresson

c) shear c) Axial bending

Unstiffened plate (U3)

c) Transverse bending

www.dnv.com


Von Misesmembrane stress distribution

Deflections for combined load case- bending + shear

Raleigh - Ritz discretizations, Fourier expansion

Buckling mode Deflection :

U3 boundary conditions:

i) simply supported out of plane along all edges

ii) straight but moveable in-plane edges (2D-integrated element)

Unstiffened plate: Theoretical model

∑∑

∑∑ππ

=

ππ=

m nmn0

m nmn

byn

axmByxw

byn

axmAyxw

)sin()sin(),(

)sin()sin(),(

www.dnv.com


- Ultimate Capacity: Integrated elements (deck, ship side, shipbottom, bulkheads etc)

- Buckling Capacity: Other elements such as girders and stringers.Elastic buckling (eigenvalue cut-off) and yield squash are upper limits

Aspect ratio limit: L1/L2 < 20 for L1 > L2 (or equivalent L2/L1 < 20 for L1 < L2) Plate slenderness ratio: Li/tp < 200 (Li = minimum of L1 and L2)

Ultimate strength=

Redistribution of stresses

Unstiffened plate (U3): Areas of application

Validity range:

www.dnv.com


a) b)

c) d)

Example: Unstiffened plate, combined loads (U3)

www.dnv.com


Slicing in 3-dim PULS ULS limit state EGG10 mm plate, UltimateCapacity curves

50 mm plate ≅Von Mises yield

Fixed shearstress slices = prestress

Bi-axial load space

Example: Unstiffened plate, Capacity curves for combined loads

www.dnv.com


0

0.2

0.4

0.6

0.8

1

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3

slenderness lam = sqrt(sigf/LEB)

Stre

ngth

sig

/sig

f

ULS - PULS 1.5-1LEB PULS 1.5-1J-O (DNV ship rules)Eurocode 3 (5.3.5)

Fig.1 Comparisons between codes: Unstiffened plate in axial compression DNV ship rules, Eurocode 3, PULS 1.5-1 code; U1-unstiffened plate, ULS and elastic eigenvalue LEB Case: Sigf = 235 MPa, E = 208000 Mpa, ny = 0.3, L = 4000 mm, s = 1000 mm, variable platethickness

Load

Deflection

ULS ; max load capacity

Elastic buckling load, eigenvalue LEB

Present rules =LEB cut-off

ULS ; max load capacity

Example: Unstiffened plate, axial compression (U3)

www.dnv.com


Typical buckling modes in stiffened panels

PULS buckling code

a) Weak/thin plate - strong stiffener sideways: thinplate/wide stiffenerflange

b) Weak stiffener sideways/torsional: High stiffener/small flange

a) + b) effekt interactingc) Weak stiffener out-of-plane: Low stiffenerheight/long span/small flange: prevented by PULS design principles

Stiffened panel (S3)

www.dnv.com


I) Local buckling accepted:elastic over-critical strength utilised

II) Prevent permanent deformations

III) Overallbuckling

notaccepted

PULS - ULS design principles – S3 element

Stiffened panel (S3): Principles

www.dnv.com


S3 element Stiffened Panel model = equivalent orthotropic material

κ∆κ∆κ∆ε∆ε∆ε∆

=

∆∆∆∆∆∆

3

2

1

3

2

1

333231332313

232221322212

131211312111

333231333231

232221232221

131211131211

3

2

1

3

2

1

DDDQQQDDDQQQDDDQQQQQQCCCQQQCCCQQQCCC

MMMNNN

Macro material law

−+

−=

tLNA

)ν(11ν1 tEC

2

s22

L11

tLNI

)ν12(11)ν12(1

tED 32

s22

3L

11

−+

−=

2

sL11 L

NSEQ −=

membranebendingCoupling bending/membrane


www.dnv.com


S3 element: Orthotropic Macro Material –

Reduction of stiffness coefficients due to local plate/stiffener buckling

Orthotropic plate theory

terms order higher

DDDQQQDDDQQQDDDQQQQQQCCCQQQCCCQQQCCC

MMMNNN

3

2

1

3

2

1

333231332313

232221322212

131211312111

333231333231

232221232221

131211131211

3

2

1

3

2

1

+

κ∆κ∆κ∆ε∆ε∆ε∆

=

∆∆∆∆∆∆

NL

NL

NL

QQQ

DDD

CCC

αβαβαβ

αβαβαβ

αβαβαβ

+≡

+≡

+≡

Local buckling/stiffness reduction :Non-linear effect


www.dnv.com


Stiffened panel (S3): Local buckling modes

Fixed

y

z

x

Clamped mode plate deflection

Longitudinal plate deflection

Simply supported mode plate deflection

Web bending

Stiffener torsion

• Local buckling: Assume no vertical deflection of stiffener• Ship design: Stocky stiffeners, local buckling accepted but global deflection

is unwanted

www.dnv.com


Stiffened panel (S3): Local buckling modes

• Plate deflection:

• Stiffener deflection:

y

z

b

v2v1

∑∑∑∑= == =

π−

π+

ππ=

Mc

1m

Nc

1n

cmn

Ms

1m

Ns

1n

smnl b

yn21a

xm2

Ab

yna

xmAyxw ))cos()(sin()sin()sin(),(

∑∑==

ππ−+

π=

Ms

1mm2

Ms

1mm1 a

xmVh2z1

axmV

hzxv )sin())cos(()sin()(

www.dnv.com


Stiffened panel (S3): Local model assumptions

• Rotational continuity

• Longitudinal continuity

0y0z yw

zv

== ∂∂

−=∂∂

∫∫ =a

sx

a

px dxudxu ,, P

www.dnv.com


Stiffened panel (S3): Local model - validation

0 0.5 1 1.5 20

0.5

1

1.5

εx/ε

f

σx/σ

f

Model Abaqus

0 1 2 30

0.1

0.2

0.3

0.4

0.5

0.6

0.7

εy/ε

f

σy/σ

f

Model Abaqus

Angle bar stiffener, from bulk carrier bottom:

Axial load Transverse load

www.dnv.com


Stiffened panel (S3): Global buckling model

• Anisotropic plate model• Structural anisotropic stiffness

derived from local analysis• One-way interaction from local to

global B

a

x

y

Cijkl

www.dnv.com


Stiffened panel (S3): Global deflection modes

• Deflection shape:

• Clamped mode accounts for lateral pressure

Sx Sx

p

∑∑∑∑= == =

−+=Mc

m

Nc

n

cmn

Ms

m

Ns

n

smng B

ynaxmA

byn

axmAyxw

1 11 1)sin())2cos(1(

2)sin()sin(),( ππππ

www.dnv.com


Stiffness reduction due to local buckling

• Global incremental force-displacement relation:

• Stiffness coefficients:

• Nonlinear parts derived from local analysis:

NLij

Lij

j

iij CCNC +=

∂∂

=ε

j

mn

mn

NLi

j

NLiNL

ijA

ANN

Cεε ∂

∂∂∂

=∂∂

=

∆Ni=Cij∆εj

www.dnv.com


Stiffness reduction due to local buckling

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8

−0.5

0

0.5

1

εx/ε

f

C11

/C11L

C22

/C22L

C12

/C12L

Q11

/Q11L

Q12

/Q11L

D11

/D11L

Dn11

/Dn11L

Angle bar stiffener, from bulk carrier bottom:

www.dnv.com


Stiffened panel (S3): Global buckling - validation

Aluminium panel, from passenger vesselCombination of lateral pressure and transverse compression:

www.dnv.com


PULS - S3 Ultimate limit statesUsage factor assessment - safety margin

1

L2

L1

1

1

1

1

23

23

4

5

f(i) (N1, N2,N3) > 0 i = 1, 2, 3, 4, 5

-1.5

-1.25

-1

-0.75

-0.5

-0.25

0

0.25

0.5

0.75

1

1.25

1.5

-1.5 -1.25 -1 -0.75 -0.5 -0.25 0 0.25 0.5 0.75 1 1.25 1.5

σ1/σyp

σ2/σyp

Limit state 1Limit state 2Limit state 3Limit state 4Limit state 5Lu

L0

5 limit states inhard corner sections

Usage factor

η = L0/Lu

N1

N2

N1

N1

N2

N2

Stiffened panel (S3): Limit States

www.dnv.com


Stiffened panel (S3): Limit States

Fig. 9 Stress control points in critical positions in a panel defining the ultimate limit states

The six limit states fi’s are stress controls in the following positions: i = 1; Plate criterion: Stress control along plate edges – based on max edge stresses along

supported edges (typical: transverse load when local buckling dominates) i = 2; Stiffener tension criterion: Stress control in stiffener; at midspan x1 = L1/2 ; in stiffener

flange for global panel deflecting towards stiffener flange, tension criterion - rare for compressive loads, but kicks in for tension loads (will also kick in for transverse compressive loads for panel with small stiffeners, i.e. large global effects)

i = 3; Plate compression criterion: Stress control in plate; at midspan x1 = L1/2; in plating for global panel deflecting towards stiffener flange, compression criterion (PI collapse)

1 3

2

4

5

6

i = 4; Stiffener compression criterion: Stiffener criterion Stress control in stiffener; at midspan x1 = -L1/2: in stiffener flange for global panel deflecting towards plating, compression criterion (SI collapse) (typical for pure axial load)

i = 5; Plate tension criterion: Stress control in plate; at midspan x1 = -L1/2; in plating for global panel deflecting towards plating, tension criterion – rare for compressive loads, but kicks inn for tension loads

(Note that the limit state criteria i = 2-5 is not always evaluated at midspan. Maximum

curvature in x1 – direction, and thereby the highest bending stress, could be closer to the ends for certain geometrical proportions of stiffened panels. Typical are cases with small stiffeners for which the panel behaves more as a plate than a “column”, with a global buckling mode pattern flattening in the mid-regions.)

i = 6; Stiffener bending stress criterion at support: Stress and capacity control at support x1

= 0; compressive or tension criterion, kicks in for cases with lateral pressure. This limit state is used to control the bending and shear capacity of the stiffeners under the influence of combined lateral load and in-plane loads. Yielding in the stiffener flange at the transverse frames is accepted, since stiffeners have significant strength reserves after first yield when subjected to lateral pressure. The panel is loaded until the plastic capacity of the stiffeners is reached. Two criteria are used for this limit state. The first is the capacity of the top and bottom flanges to carry the combined axial force and bending moment resulting from the applied loads, and the second is the capacity of the web to carry the shear force and axial force due to the applied loads.

www.dnv.com


Web slenderness for flat bar stiffeners: 35 Web slenderness for L or T profiles: 80t/h ww <

Free flange for L or T profiles: 10t/f ff < Plate between stiffeners: 200t/s < Aspect ration of plate between stiffeners 0.25 < L1/s <10 *

Validity range for stiffened panel:- Ultimate Capacity; integrated elements; deck, ship side, ship bottom, bulkheads etc.

Stiffened plate (S3): Validity range

www.dnv.com


PULS 2D Capacity CurvesSlice in 3-dimensional limit state surface egg

Example: Biaxial loads on stiffened panels

ULS Capacity Curve, bi-axial loads, design load combination to be insideenvelope with specified rule margin

Elastic buckling cut off for thin plates (Eigenvalue curve-LEB)

Region of Elastic buckling. Elastic bucklingaccepted for extreme loads…plate returns to original shape after unloading (no permanent buckles)

Stress redistributionfrom plate to stiffeners: Plate is hanging onstrong stiffeners!!!

σ1

σ2

Example: Stiffened plate, axial compression (S3)

www.dnv.com


Stiffened plate, non-regular geometry (T1)

Complex geometry, simplified theory:

• Analysis of stiffened panels with arbitrary oriented stiffeners

• Based on linear theory• Ultimate limit state estimates based

on hot spot stress control, but limited by linear elastic eigenvalue

www.dnv.com


PULS validation against

non-linear FE/ABAQUS

Trogir 302(L-stiffener and plate thickness: 13.5 mm

without pressure)

0

20

40

60

80

100

120

140

0 50 100 150 200 250 300

σ1

σ2

Abaqus

PULS

PULS (Eigenvalue)

Bottom panel Tanker Lpp =170 m

Trogir 302(L-stiffener and plate thickness: 13.5 mm

pressure: 151.1 kN / m2)

0

20

40

60

80

100

120

140

0 50 100 150 200 250 300

σ1

σ2

Abaqus PULS

PULS validation

www.dnv.com


PULS validation against GL lab test (Egge/95)

GL experimental test model-4 "as measured yield stresses" in PULS analysis

PULS 1.5-0; bi-axial capacity curves

-200

-100

0

100

200

300

-200 -100 0 100 200 300

Axial stress σ1 [MPa]

trans

vers

e st

ress

σ2

[MPa

]

PULS 1.5 with p = 0.0

PULS 1.5 with p = 2.40 Wh

Local eigenvalues (PULSLEB)GL test (185,50) and p = 2.40Wh)

GL experimental test model-3 "as measured yield stresses" in PULS analysis

PULS 1.5-0; bi-axial capacity curves

-200

-100

0

100

200

300

-200 -100 0 100 200 300

Axial stress σ1 [MPa]

trans

vers

e st

ress

σ2

[MPa

]

PULS 1.5 with p = 0.0

PULS 1.5 with p = 5.30 Wh

Local eigenvalues (PULSLEB)GL test (190,69) and p = 5.30Wh)

PULS validation

www.dnv.com


PULS validation- Extensive comparisons against non-linear FE/ABAQUS

- Limited comparisons against lab tests (Ex: GL/Egge 95)

- Comparisons against against existing rules

Conclusions- Very satisfactory quantiative comparisons ABAQUS and lab tests; mostly within ± 10%

- Same qualitative physical behaviour as seen in ABAQUS and lab tests

PULS: Sound physical models for robust designs

PULS For easy use

Designers, Non-experts etc.

PULS validation

www.dnv.com


2 different PULS Stand alone programs

2. PULS Excel spreadsheet version, features:

- Material Optimization studies, parameter variasjons

1. PULS General User Interface (GUI) Version, features:

- Visual Basic user interface. Very simple and intuitive to use

- Single parameter output for any load combination: Usage factor measured against accept levelin rules

- Full 3D graphics for illustration of buckling modes, redistributed stress pattern etc.

- 2D capacity curve illustration of ULS and elastic buckling limits for combined loads - slicesin 3-dimensional limit state surface egg

- Animation of non-linear buckling process

Profile table; Bulbs, Angles etc

Same input file

PULS Software

www.dnv.com


U3 element: Integrated unstiffened plate

Output:i ) Elastic buckling stresses (LEB; eigenmode)

ii) ULS strengh (max capacity)

iii) ULS membrane stresses

iiv) Single parameter strength evaluation : usage factor

PULS General User Interface Application

Input:i ) Geometry

ii) Material

iii) Loads

www.dnv.com


PULS General User Interface Application

S3 element: Integrated stiffened plate

Input:i ) Geometry

ii) Material

iii) Loads

Output:i ) Elastic buckling stresses (LEB and GEB; eigenmodes)


iii) Local ULS membrane stresses


Profile table button

or from

Menu: define stiffener

Menu: Panel/Secondary stiffeners

www.dnv.com


PULS Excel Application

Input:i ) Geometry

ii) Material

iii) Loads

Output:i ) Elastic buckling stresses (LEB and GEB; eigenmodes)


iii) Local ULS membrane stresses


Profile table button

or from

Menu: define stiffener

Menu: Panel/Secondary stiffeners

www.dnv.com


PULS Excel Application

Parameter study using PULS

Changing thickness, all other parameters fixed Change in usage factor due to thickness change

www.dnv.com


PULS 2.0 release, April 2004

Improvements: • Automatic smoothening routine of Capacity Curves/Surfaces for bi-axial compression (reduce ”bumps”)

• Modified lateral pressure model, minor changes

• Increased slenderness range of stiffener web and flange (h/tw < 90 (80), ff/tf < 15 (10))

PULS 2.0 versus 1.5

New technical features:• S2 stiffened plate element renamed S3 with new features

• S3: Linearly varying stress perpendicular to primary stiffeners

• S3: Boundary conditions: Option for free to pull in edges (non-linear effect - minor interest for normal ship scantlings )

• U1 unstiffened plate renamed U3 with new features

• U3: Boundary conditions; Option for clamped or rotational restrained edges

• New element T1: Non-regular stiffening arrangement, triangular plates etc.

www.dnv.com


PULS 2.0 release, April 2004

PULS 2.0

New software features, Explorer user interface:• S3: Visualization of secondary stiffeners (run perpendicular to main stiffeners)

• S3, U3: Extra tab strip for boundary conditions

• S3, U3: Improved pressure plot of plate and stiffener deflections

•S3: Weakest link: identfies max. deflections in plates and stiffeners – useful design info

•S3, U3 : New Excel Report generator, summarize input and output results

New software features, Excel user interface:• S3: Optimisation of stiffener/plate geometry, fixed weight/cross-sectional area

• S3: Weakest link: identfies max. deflections in plates and stiffeners – useful design info

www.dnv.com


PULS 2.0 download and installation

• Go to the internet page: http://www2.dnv.com/software/Products/Nauticus/puls/puls.htm

• Click on ”Download PULS”• Write in name etc., and click ”Download PULS”• Choose ”Save”, pick a directory for the download, and click ”Close”

when download is complete• Go to your PULS directory, and unpack the .zip-file• Start the installation by double-clicking the setup.exe-file• Execute PULS from the Start-meny

dnv’s puls buckling code panel ultimate limit state new ... puls... · structural design - ships...

Documents