This engineering study evaluated the structural integrity of using a ballasted barge as the test weight for overload tests of a crane barge with a maximum capacity of 2050 tons. Finite element modeling was conducted using SESAM software to analyze the stresses on the test barge under 5 planned loading conditions up to a maximum of 2255 tons. The results indicated the test barge structure is adequate and the overload tests can proceed in January 2013 as scheduled.

1. Engineering Study for Barge Lifting Weight on Crane Barge
Overload Test
Bernardo Xavier
Guilherme Leal
Thayanna Araujo
Rio de Janeiro – 03/12/2012

2. Motivation
Typical crane overload test description;

3. Motivation
Load curve estimate for overload test procedures;

4. Motivation
Simple engineering for overload test weight determination;
Overload test engineering becomes tricky when lift weight
increases;
- HARD TO CALIBRATE
- DINAMIC BEHAVIOUR

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

6. Objectives
- 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: Test barge main particulars
Length over all 110 m Length over all 59.90 m
Molded breadth 39 m
Molded breadth 21.36 m
Molded depth 7 m Molded depth 4.2 m
Main hook capacity 2050 ton Deadweight 3000 ton

7. Design premisses
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:
Load Condition Total (ton)
1 720.72
2 1186.15
3 1596.45
4 1782.02
5 2255.02
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;

8. Design premisses
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;

9. Design premisses
Structural evaluation of test barge (DEC Criteria);

10. Lifting configuration
Typical spreader bar scheme;

11. Lifting points
Typical 4 lifting point design;

12. Lifting Padeyes Design
Padeye design for SWL 650 tons based on “N2683 – Estruturas
Oceânicas – Olhal de içamento – Dimensionamento”.
Special consideration for weld shear stress stiffness and load
transfer to the test barge;

13. Engineering Study for Barge Lifting Weight on Crane Barge
Overload Test
Global FEM model
O QUE ?
COMO ?

14. Engineering Study for Barge Lifting Weight on Crane Barge
Overload Test
Global FEM model mesh size = 0.5m;
O QUE ?
COMO ?

15. Engineering Study for Barge Lifting Weight on Crane Barge
Overload Test
Typical ballasted load condition;

16. Engineering Study for Barge Lifting Weight on Crane Barge
Overload Test
Local FEM model

17. Engineering Study for Barge Lifting Weight on Crane Barge
Overload Test
Local FEM model mesh size = 0.05m;

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

19. 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.

20. Engineering Study for Barge Lifting Weight on Crane Barge
Overload Test
Bending moments x length Normal Stresses x length
2,00E+05
3,00E+07
1,50E+05
Bending Moment (Pa)
2,00E+07
1,00E+05
Normal Stress (Pa)
5,00E+04 1,00E+07
0,00E+00 0,00E+00
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
-5,00E+04
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
-1,00E+07
-1,00E+05
-1,50E+05 -2,00E+07
-2,00E+05 -3,00E+07
Length (m) Length (m)
Shear Stresses x length
3,00E+06
RESULTS ARE IN
2,00E+06
Shear Stress (Pa)
1,00E+06
0,00E+00 ACCORDANCE WITH
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
-1,00E+06
-2,00E+06 FEM ANALYSIS
-3,00E+06
-4,00E+06
Length (m)

21. 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;

22. Conclusion
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;