SUC Brasil 2012 : Engineering Study for Barge Lifting Weight on Crane Barge Overload Test

Engineering Study for Barge Lifting Weight on Crane Barge Overload Test Bernardo Xavier Guilherme Leal Thayanna Araujo

Rio de Janeiro – 03/12/2012

Typical crane overload test description;

Motivation

Load curve estimate for overload test procedures;

Motivation

Simple engineering for overload test weight determination; Overload test engineering becomes tricky when lift weight increases;

Motivation

- HARD TO CALIBRATE - DINAMIC BEHAVIOUR

Solution? - Modify the concept of the test weight. Engineering? - Loading conditions and draft marks definition; - Evaluation of the structural integrity of the test barge and lifting

padeyes;

Motivation

TEST BARGE

- Engineering study for crane overload test for SWL 2050 tons maximum load curve; - Test weight shall be a calibrated ballasted deck barge; Crane barge main particulars:

Objectives

Length over all 110 m Molded breadth 39 m

Molded depth 7 m

Main hook capacity 2050 ton

Test barge main particulars

Length over all 59.90 m Molded breadth 21.36 m

Molded depth 4.2 m Deadweight 3000 ton

The maximum overload weight shall be 2255 tons, which considers a 10% overload factor of a maximum safe working load of 2050 tons. A total of five loading conditions shall be tested: The test barge was carefully selected for the lifting weight purpose in which shall be fully lifted out of the water in order to provide a accurate and realistic results of the overload test as well as the calibration of the load cells for the crane barge;

Design premisses

Load Condition Total (ton) 1 720.72 2 1186.15 3 1596.45 4 1782.02 5 2255.02

For structural integrity analysis, DNV SESAM software package was used: - GeniE V5.3-10: Local and global structural analysis; - SESTRA 8.4-01: Linear Structural analysis - Submod V6.1-05: Submodeling coupling from global to local FE model; - Xtract 3.0-00: Post-process of the structural results;

Design premisses

Structural evaluation of test barge (DEC Criteria);

Design premisses

Typical spreader bar scheme;

Lifting configuration

Typical 4 lifting point design;

Lifting points

Padeye design for SWL 650 tons based on “N2683 – Estruturas Oceânicas – Olhal de içamento – Dimensionamento”.

Lifting Padeyes Design

Special consideration for weld shear stress stiffness and load transfer to the test barge;

Engineering Study for Barge Lifting Weight on Crane Barge Overload Test

O QUE ?

COMO ?

Global FEM model

Engineering Study for Barge Lifting Weight on Crane Barge Overload Test

O QUE ?

COMO ?

Global FEM model mesh size = 0.5m;

Engineering Study for Barge Lifting Weight on Crane Barge Overload Test

Typical ballasted load condition;

Engineering Study for Barge Lifting Weight on Crane Barge Overload Test

Local FEM model

Engineering Study for Barge Lifting Weight on Crane Barge Overload Test

Local FEM model mesh size = 0.05m;

Engineering Study for Barge Lifting Weight on Crane Barge Overload Test Von mises stress results (Max allowable = 225 MPa) (Max load case);

Engineering Study for Barge Lifting Weight on Crane Barge Overload Test

Analytical hull girder bending check;

Bending moments, normal stresses and shear stress along the hull.

Engineering Study for Barge Lifting Weight on Crane Barge Overload Test

-2,00E+05-1,50E+05-1,00E+05-5,00E+040,00E+005,00E+041,00E+051,50E+052,00E+05

0,5 4

7,5 11

14,5 18

21,5 25

28,5 32

35,5 39

42,5 46

49,5 53

56,5

59,9

Bend

ing

Mom

ent (

Pa)

Length (m)

Bending moments x length

-3,00E+07

-2,00E+07

-1,00E+07

0,00E+00

1,00E+07

2,00E+07

3,00E+07

0,5

3,5

6,5

9,5

12,5

15,5

18,5

21,5

24,5

27,5

30,5

33,5

36,5

39,5

42,5

45,5

48,5

51,5

54,5

57,5

Nor

mal

Str

ess

(Pa)

Length (m)

Normal Stresses x length

-4,00E+06

-3,00E+06

-2,00E+06

-1,00E+06

0,00E+00

1,00E+06

2,00E+06

3,00E+06

0,5 4

7,5 11

14,5 18

21,5 25

28,5 32

35,5 39

42,5 46

49,5 53

56,5

59,9

Shea

r Str

ess (

Pa)

Length (m)

Shear Stresses x length

RESULTS ARE IN ACCORDANCE WITH FEM ANALYSIS

Advantages of using SESAM software

• User friendly interface for complex geometry modeling;

• Easy to model structures which optimizes precious time on overall

project schedule;

• Great result analysis tools for stress plots;

SESAM software package was highly suitable for the proposed study in which demonstrated that the test barge has adequate structural integrity for the proposed loading conditions; Crane barge overload actual test is scheduled for January 2013;

Conclusion