Displacement pada brace joint untuk Load Case JR18O-270MX

Displacement pada brace joint untuk Load Case JR18O-315MX

Node Joint

ANSYS MicroSAS x y z

50004 L128 8.70E-04 2.65E-03 -1.63E-03

50010 325 4.26E-04 1.95E-03 -1.01E-03

50038 181 2.16E-03 2.87E-03 4.34E-04

50026 225 1.48E-03 4.83E-03 7.35E-04

50032 L110 1.63E-03 3.28E-03 1.29E-03

50020 224 2.13E-03 2.75E-03 1.15E-03

Displacement (meter)

Displacement pada brace joint untuk Load Case JR03E-045MN

Displacement pada brace joint untuk Load Case JR18E-315MN

Node Joint

ANSYS MicroSAS x y z

50004 L128 4.80E-04 3.05E-03 -3.73E-03

50010 325 1.66E-04 2.22E-03 -3.32E-03

50038 181 4.49E-03 1.88E-03 3.03E-03

50026 225 2.26E-04 6.89E-03 1.72E-03

50032 L110 1.09E-03 2.58E-03 5.23E-03

50020 224 5.19E-03 -2.55E-03 5.24E-03

Displacement (meter)

1. ASME B31.4-2006, Pipeline Transportation Systems for Liquid Hydrocarbons and other Liquids.

Max. Allowable Von Mises Stress ≤ 0.9 Specified Minimum Yield Stregth

2. ABS Safehull-Dynamic Loading Approach’ for Floating Production, Storage and Offloading (Fpso) Systems 2001, for the ‘SH-DLA’ Classification Notation.

Max. Allowable Von Mises Stress ≤ 0.9 Specified Minimum Yield Stregth

3. ABS Mobile Offshore Drilling Units 2001, Part 3: Hull Construction and Equipment.

Von Mises Stress = Yield Stregth / Factor Safety

Factor Safety ≤ 1.11 untuk beban kombinasi

Tegangan Von Mises akibat load case JR18O-270MX

Von Mises Stress Yield Stress Displacement

Mpa Mpa ASME ABS meter

Jacket Leg 160 324 291.6 291.9 0.005 PASS

Top Yoke Plate 210 345 310.5 310.8 0.007 PASS

Flange Plate 22.8 345 310.5 310.8 0.006 PASS

Bottom Yoke Plate 121 324 291.6 291.9 0.007 PASS

Main Shear Plate 171 345 310.5 310.8 0.007 PASS

External Shear Plate 174 345 310.5 310.8 0.007 PASS

Skirt Sleeve 163 345 310.5 310.8 0.008 PASS

RemarkComponent of Skirt Pile SleeveAllowable Stress (Mpa)

1

MN

MX

X

Y

Z

14906

.234E+08.467E+08

.701E+08.934E+08

.117E+09.140E+09

.163E+09.187E+09

.210E+09

DEC 30 2010

00:44:24

NODAL SOLUTION

STEP=1

SUB =1

TIME=1

SEQV (AVG)

DMX =.007319

SMN =14906

SMX =.210E+09

Tegangan Von Mises akibat load case JR18O-315MX

Von Mises Stress Yield Stress Displacement

Mpa Mpa ASME ABS meter

Jacket Leg 171 324 291.6 291.9 0.006 PASS

Top Yoke Plate 220 345 310.5 310.8 0.009 PASS

Flange Plate 30.5 345 310.5 310.8 0.008 PASS

Bottom Yoke Plate 152 324 291.6 291.9 0.010 PASS

Main Shear Plate 178 345 310.5 310.8 0.009 PASS

External Shear Plate 201 345 310.5 310.8 0.009 PASS

Skirt Sleeve 121 345 310.5 310.8 0.010 PASS

Component of Skirt Pile Sleeve RemarkAllowable Stress (Mpa)

1

MN

MX

X

Y

Z

16470

.244E+08.488E+08

.733E+08.977E+08

.122E+09.146E+09

.171E+09.195E+09

.220E+09

DEC 30 2010

00:56:03

NODAL SOLUTION

STEP=1

SUB =1

TIME=1

SEQV (AVG)

DMX =.009279

SMN =16470

SMX =.220E+09

Tegangan Von Mises akibat load case JR03E-045MN

Von Mises Stress Yield Stress Displacement

Mpa Mpa ASME ABS meter

Jacket Leg 236 324 291.6 291.9 0.012 PASS

Top Yoke Plate 292 345 310.5 310.8 0.017 PASS

Flange Plate 57.8 345 310.5 310.8 0.014 PASS

Bottom Yoke Plate 193 324 291.6 291.9 0.023 PASS

Main Shear Plate 231 345 310.5 310.8 0.017 PASS

External Shear Plate 310 345 310.5 310.8 0.017 PASS

Skirt Sleeve 89.7 345 310.5 310.8 0.022 PASS

Component of Skirt Pile Sleeve RemarkAllowable Stress (Mpa)

1

MN

MX

.184E+07

.361E+08.704E+08

.105E+09.139E+09

.173E+09.208E+09

.242E+09.276E+09

.310E+09

DEC 30 2010

01:09:03

NODAL SOLUTION

STEP=1

SUB =1

TIME=1

SEQV (AVG)

DMX =.017038

SMN =.184E+07

SMX =.310E+09

Tegangan Von Mises akibat load case JR18E-315MN

Von Mises Stress Yield Stress Displacement

Mpa Mpa ASME ABS meter

Jacket Leg 180 324 291.6 291.9 0.007 PASS

Top Yoke Plate 231 345 310.5 310.8 0.012 PASS

Flange Plate 39.3 345 310.5 310.8 0.010 PASS

Bottom Yoke Plate 210 324 291.6 291.9 0.014 PASS

Main Shear Plate 188 345 310.5 310.8 0.010 PASS

External Shear Plate 273 345 310.5 310.8 0.010 PASS

Skirt Sleeve 121 345 310.5 310.8 0.014 PASS

Component of Skirt Pile Sleeve RemarkAllowable Stress (Mpa)

1

MNMX

758312

.310E+08.612E+08

.914E+08.122E+09

.152E+09.182E+09

.212E+09.242E+09

.273E+09

DEC 30 2010

01:20:14

NODAL SOLUTION

STEP=1

SUB =1

TIME=1

SEQV (AVG)

DMX =.01047

SMN =758312

SMX =.273E+09

Kritis

◦ Load Case JR18O-270MX (operasional)

◦ Load Case JR18O-315MX (operasional)

◦ Load Case JR03E-045MN (ekstrem)

◦ Load Case JR18E-315MN (ekstrem)

JR03E-045MN → Nilai Tegangan von mises terbesar →external shear plate = 310 Mpa ≤ tegangan ijin sebesar310.5 dan 310.8 MPa pada code ASME dan ABS.

JR03E-045MN → Nilai displacement terbesar → bottomyoke plate = 0.023 meter

Syarat batas tidak seharusnya fix karena dimungkinkan adanya sifat

pegas dan redam dari bagian jacket yang tidak dimodelkan sehingga

didapatkan hasil yang mendekati kondisi lapangan.

Hasil yang diperoleh akan lebih mendekati nilai yang sebenarnya

jika karakteristik grout diterapkan pada pemodelan local dengan

menggunakan elemen dan parameter yang dapat mewakili sifat

grout.

Mesh yang lebih kecil lebih dianjurkan untuk mendapatkan hasil

yang lebih akurat tentunya dengan melakukan Mesh sensitivity

Analysis terlebih dahulu.

Menggunakan pendekatan substructure pada bagian skirt pile.

American Institute of Steel Construction, 1989, Allowable Stress Design Manual 9th

Edition. American Petroleum Institute, 2002, Recommended Practice For Planning and

Constructing Fixed Offshore Platform - Working Stress Design, API Recommended Practice 2A (RP 2A) WSD.

ANSYS Multiphysics 12, 2009, User Manual Guide, Ansys Inc.

Barltrop, N. D. P., 1988, Floating Structures: a guide for design analysis Volume One, Ledbury. England: The Centre for Marine and Petroleum Technology.

Chakrabarti, S. K., 1987, Hydrodynamics of Offshore Structure, Southampton, Boston USA: Computational Mechanics Publications.

Chakrabarti S. K., 2005, Handbook of Offshore Engineering, Plainfield, Illinois, USA: Elsevier.

Coyle, H. M., et al, 1966, Soil Mechanics and Foundations Division for Load Transfer for Axially Loaded Piles in Clay, ASCE Journal, Vol. 92, No. 1052.

Coyle, H. M., et al, 1967, Skin Friction for Steel Piles in Sand, Journal of the Soil Mechanics and Foundation Division, Proceedings of the American Society of Civil Engineers, Vol. 93, No. SM6, November, 1967, p. 261–278.

Dean, R. G., 1965, Stream Function Representation of Non-Linear Ocean Waves, Journal of Geophysical Research, Vol. 70. pp. 4561-4572.

Gerwick,Ben C. Jr., 2000, Construction of Marine and Offshore Structures Second Edition, Washington, D. C: CRC press.

Hastanto, E. S., 2005, Analisa Ultimate Strenght Struktur Jacket LE Berbasis Keandalan, Jurusan Teknik Kelautan, FTK-ITS, Surabaya.

http://www.naturalgas.org/naturalgas/extraction_offshore.asp, 11 januari 2011.

Kraft, et al, 1981, Lateral Pile Response During Earthquakes, Journal of the Geotechnical Engineering Division, ASCE, Vol. 109, No. GT12, Paper No. 16735, December 1981.

McClelland, 1986, Planning and Design of Fixed Offshore Platforms, Van Nostrand Reinhold Company: New York.

McDermott, 2008, Structural Basis of Design, Document No.: R2312-22-ST-BOD-00001.

MicroSAS, 2007, User Manual Guide, McDermott Inc. USA.

Mohd Nor, NK, 1996, FE Analysis of an Integrated Plate Connection between Jacket Structure and Skirt-Pile Sleeve, Report 96:9, Master Thesis, Department of Structural Mechanics, Chalmers University of Technology, Sweden.

Morison, J. R., et al, 1950, The Force Exerted by Surface Waves on Piles, Petroleum Transactions, American Institute of Mining and Metal Engineering, Vol. 4, pp. 11-22.

Pogonowski, 1972, Reversed Slope Skirt Pile Marine Platform Anchoring, United states Patent, Texaco Inc., New York.

Popov, E. P., 1993, Mekanika Teknik, Jakarta: Penerbit Erlangga.

Vijayvergia, V.N., 1977, Load Movement Characteristics of Piles, Proceedings of the Ports‘77 Conference, American Society of Civil Engineers, Vol. II, p. 269–284.

Will, 1987, Composite Leg Platform, United States Patent, McDermott Inc., New Orleans.

TERIMA KASIH