RESEARCH AND ENGINEERING INSTITUTE
FOR OFFSHORE OIL AND GAS
PROJECT
: KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
SUB PROJECT
: CPP KNT
DOCUMENT TITLE : TOPSIDE STRUCTURE - WALLS DESIGN (FENDER
AND FIRE/BLAST WALL)
DOCUMENT NO.
: KNT-002-TS-ST3-CA-002
Job Name:
Phase:
DETAILED ENGINEERING
Job Number:
0
IFA
27.03.23
N.T. TRUNG
N.V. DIEP
T.D.HAI
B.T.HAN
REV.
DES.
DATE
PREPARED
LEAD
ENGINEER
ENG.
MANAGER
PROJECT
MANAGER
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
KNT-002-TS-ST3-CA-002
Rev.
0
Page
2 of 30
TRACK CHANGES
No
Rev.
Content of Change
1
A
Issued for Review
2
0
Issued for Approval
Note
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
KNT-002-TS-ST3-CA-002
Rev.
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TABLE OF CONTENTS
1
INTRODUCTION..................................................................................................................... 4
1.1 Definition and Abbreviation .............................................................................................. 6
1.1.1
Definition .................................................................................................................. 6
1.2 Purpose of Document ...................................................................................................... 7
1.3 Design life ........................................................................................................................ 7
1.4 Slenderness Ratio ........................................................................................................... 7
1.5 Deflection ......................................................................................................................... 7
2
REFERENCE DOCUMENTS .................................................................................................. 8
2.1 Codes & Specifications .................................................................................................... 8
2.2 Other Technical Documents ............................................................................................ 8
3
DESIGN DATA AND ASSUMPTIONS ................................................................................... 9
3.1 Material Properties........................................................................................................... 9
3.2 Steel Wall Profiles.......................................................................................................... 10
3.3 Design Wind Load ......................................................................................................... 10
3.4 Design Summary ........................................................................................................... 11
4
3.4.1
Fender Design........................................................................................................ 11
3.4.2
Firewall Design ....................................................................................................... 11
3.4.3
Blast-Wall Design ................................................................................................... 11
FENDER DESIGN................................................................................................................. 12
4.1 Design Criteria ............................................................................................................... 12
4.2 Design Results............................................................................................................... 12
5
FIREWALL DESIGN ............................................................................................................. 13
5.1 Design Criteria ............................................................................................................... 13
5.2 Design Results............................................................................................................... 13
6
BLAST-WALL DESIGN ........................................................................................................ 14
6.1 Design Criteria ............................................................................................................... 14
6.2 Design Results............................................................................................................... 14
APPENDICES ................................................................................................................................. 15
APPENDIX A: FENDER DESIGN ...................................................................................... 16
APPENDIX B: FIREWALL DESIGN ................................................................................... 19
APPENDIX C: BLAST-WALL DESIGN .............................................................................. 23
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
1
KNT-002-TS-ST3-CA-002
Rev.
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INTRODUCTION
Kinh Ngu Trang and Kinh Ngu Trang Nam fields belong to Block 09-2/09 in Cuu Long Basin
offshore southern Vietnam. Kinh Ngu Trang field locates in distance approximately 150km
from Vung Tau city, 40 km from the East of White Tiger field, 14 km from Rang Dong field and
25 km from Ca Ngu Vang field. Kinh Ngu Trang Nam field locates in distance 3.5km from Kinh
Ngu Trang field. Sea water depth at the Kinh Ngu Trang and Kinh Ngu Trang Nam locations is
approximately 65m.
Fig.1: Location of KNT/KTN fields at Block 09-2/09
The development of Block 09-2/09 was started since 2019 when Petroleum Sharing Contract
(PSC) was signed between JV Vietsovpetro (VSP) 40%, PVEP- 30% and AO Zerubezhneft30%. VSP took the operatorship of Block 09-2/09.
The field development of Kinh Ngu Trang and Kinh Ngu Trang Nam consists of installation of
two (02) offshore platforms namely CPP KNT and WHP KTN, in-field pipelines, inter-field
pipelines, submarine cable and modification on the existing platforms at White Tiger Field. The
CPP KNT will be located at Kinh Ngu Trang field and designed as a Central Processing
Platform, equipped with full process and utility facilities to ensure the safe and effective oil &
gas production of Block 09-2/09. WHP KTN will be located at Kinh Ngu Trang Nam field and
will be designed as an unmanned wellhead platform, which is monitored and controlled
remotely from CPP KNT. The production fluid of Kinh Ngu Trang and Kinh Ngu Trang Nam
fields will be gathered and processed on CPP KNT to meet the export conditions and selfsufficiently supply of the gaslift, fuel gas and electrical power for internal field’s demands. After
the processing on CPP KNT, including separation, heating, compression and pumping, the
mixture of gas and liquid will be transported to MSP-10 platform at White Tiger field via 38.8
km of subsea pipeline. At MSP10, the oil gas mixture from CPP KNT will be routed to new
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
KNT-002-TS-ST3-CA-002
Rev.
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process facilities to separate the liquid and gas, conduct the allocation measurement before
export the gas to MKS platform for compression, liquid to CPP2/CPP3 for further processing to
meet the commercial requirement before offloading. The water injection for Kinh Ngu Trang
and Kinh Ngu Trang Nam fields will be supplied from BK-15 platform on White Tiger field via
35.8 km of subsea pipeline.
In addition, to ensure the power supply capacity for serving the connection of Kinh Ngu Trang
& Kinh Trang Nam fields, a modification for installation of new transformer sub-station 2500
KVA on MSP9 platform will be conducted. The power supply to MSP10 platform via the
existing submarine cable 6.3 kV MSP9-MSP10.
Scheme of Kinh Ngu Trang and Kinh Ngu Trang Nam field development is shown in figure 2.
Fig. 2: Development scheme of Block 09-2/09
The field development of Kinh Ngu Trang and Kinh Ngu Trang Nam is intended to allow for the
installation of offshore facilities in 2023-2024 years, and have First Oil in 4th Quarter of 2024
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
1.1
Definition and Abbreviation
1.1.1
Definition
KNT-002-TS-ST3-CA-002
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PROJECT
KINH NGU TRANG – KINH NGU TRANG NAM FIELD
DEVELOPMENT, BLOCK 09-2/09
SUB-PROJECT
CPP KNT
COMPANY
VIETSOVPETRO JOINT VENTURE [VSP]
ENGINEERING
CONTRACTOR
RESEARCH AND ENGINEERING INSTITUTE [REI]
CONTRACTOR
Party which carries out all or part of the design, engineering,
procurement, construction and commissioning of the project
VENDOR (or SUPPLIER)
The person, group or organization responsible for the design,
manufacture, testing and load-out/shipping, installing of the
equipment
SUB-VENDOR
The person, group or organization who may be employed by
the Vendor to provide services for the design, manufacture,
testing and load-out/shipping, installing of the equipment or to
provide materials, sub-components and sub-assemblies for
incorporation in the equipment packages
THIRD PARTY
An Independent 3rd Party Certifying Authority appointed by
Vendor approved by the Company for certifying specific
equipment/equipment packages fabricated at Vendor’s shop
INSPECTOR
Company appointed person, group or organization acting in
behalf of the Company responsible for inspection and witness
testing of equipment/ equipment packages at Vendor’s shop
CERTIFYING
AUTHORITY (CA)
Independent agency contracted by the Company to provide
Classification/ Certification services to Field Development
Project’s facilities from design review to construction &
commissioning (startup) in accordance with CA Rules &
Regulations, applicable Codes, Standards & Vietnamese
Register (VR) Regulations.
May
Indicates possible course of action.
Shall
Indicates mandatory requirements
Should
Indicates preferred course of action.
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
1.2
KNT-002-TS-ST3-CA-002
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Purpose of Document
This document is the design of the miscellaneous topsides structural components that are not
in the analysis reports: This includes:
1) Fender design
2) Fire-wall design
3) Blast-wall design
The design spreadsheets, computer listing extracts and reference drawings are in the
respective appendices.
The structural analysis and design are carried out based on the design parameters stipulated
in the structural design basis. The structural analyses adopted the Working Stress Design
method, and they are performed in accordance with API RP 2A-WSD and AISC (Allowable
Stress Design).
1.3
Design life
The design life of the platform is 25 years.
1.4
Slenderness Ratio
All main structural members should be designed to satisfy the following limits:
Maximum Slenderness Ratio (KL/r)
Member
Compression
Primary/Secondary
1.5
120
Tension
200
Where L
=
un-braced member length
R
=
radius of gyration
K
=
effective length factor (as per API RP-WSD)
Deflection
The maximum relative deflection of a structural member shall be limited so that it will not
neither impair the strength of the structure nor the operating efficiency of any plant or
equipment, which it supports.
Relative deflections of structural elements, under imposed loads, shall be within limits set here
under:

Primary Beams
: Span/360

Secondary Beams
: Span/240

Cantilevers
: Span/180

Plates
: Span/200
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
2
KNT-002-TS-ST3-CA-002
Rev.
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REFERENCE DOCUMENTS
The following codes, specifications, standards, and references were used for the design of the
KNT Topside Structure.
2.1
2.2
Codes & Specifications
Ref.
Document No.
Rev.
1
API RP2AWSD
22nd edition
Planning, Designing, and Constructing Fixed
Offshore Platforms – Working Stress Design,
November 2014.
2
AISC
13th edition
Manual of Steel Construction, 2005.
(For structural shapes and properties only)
3
AISC 355-89
4
Lloyd’s
Register
5
API RP 2FB
-
Description
Specification for Structural Steel Buildings,
Allowable Stress Design and Plastic Design, June
1989.
Rules and Regulations for the classification of a
floating offshore installation at a fixed location,
part 4 – Steel Unit Structures, April 2008
1st Edition
Recommended Practice for the Design of
offshore Facilities Against Fire and Blast loading
Other Technical Documents
Ref.
Document No.
Description
6
KNT-002-TS-ST3-DB-001
Topside Structural Design Basis & Design Brief
7
KNT-002-GE-ST3-SP-003
Specifications for Structural Steel Material
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
3
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DESIGN DATA AND ASSUMPTIONS
The following design data and assumptions are used in this report
3.1
Material Properties
The specification of steel material refers to document “KNT-002-GE-ST3-SP-003 Specification for Structural Material”.
The following characteristic properties shall be used for analyses and design:
Density in air
: 7850 kg/m3
Young's Modulus, E
: 210,000 Mpa
Shear Modulus, G
: 80,000 Mpa
Poisson's ratio, μ
: 0.300
Coefficient of thermal expansion
: 11.7 x 10-6/°C
Friction coefficient (steel to steel)
: 0.200
The Table 3.1 is shown material steel grade from material specifications used for design.
Table 3.1: Material Specification
Type
I
II
III
IV
Material Grade
API 2H Grade 50 with S1,
S3, S4, S5 and S8
Requirements
API 2W Grade 50Z with S1,
S3, S4, S5 and S8
Requirements
API 2W Grade 50 with S1,
S3, S5 and S8
Requirements
API 5L Grade X52 with SR4,
SR5 and SR17
Requirements
ASTM A572 Grade 50 or
Equivalent
ASTM A131 Grade AH36 or
Equivalent
ASTM A36 or Equivalent
General
Description
Typical Uses
Primary High
Strength with
through
thickness
property
Jacket and
Topside Joint
Cans and Plates
for Lift Point
Primary High
Strength
Jacket and
Topside
Rolled/seamless
Tubulars; Plates
Primary High
Strength
Plates, Hot
Rolled Shapes
Secondary Mild
Strength
Plates, Hot
Rolled Shapes
Material
Yield
Class
(API)
Strength
(MPa)
Tensile
Strength
(MPa)
II-A
345 Min.
483 Min.
345 Min.
483 Min.
360 Min.
460 Min.
345 Min.
450 Min.
355 Min.
490 Min.
250 Min.
400 Min.
II-A
II-C
II-B
I-C
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
3.2
KNT-002-TS-ST3-CA-002
Rev.
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Steel Wall Profiles
The profile of steel walls selected as follow:
3.3
Design Wind Load
The design wind speeds from table 3-3 of the Topside Structural Design Basis & Design Brief
[6] will be adopted for the design. They are reproduced in table below.
Table 3.2 – Design wind speed – Steel wall for fender
Wind Velocity (m/s)
Return Period
1-minute mean
3 second mean
1-year Storm – Operating Condition
26.5
29.6
100-year Storm – Extreme Condition
50.3
56.3
3-second in-line wind velocity in extreme storm condition is to be used for local steel wall
design. All wind speeds are referenced to 10 m level above the MSL. Variation of wind velocity
with height is to be calculated in accordance with API RP 2A.
The wind velocity at specified height may be taken as:
1
 Z n
VZ  VR 
 ( m/s )
 ZR 
Where:
VZ: Wind velocity at specified height Z (m), m/s
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
KNT-002-TS-ST3-CA-002
Rev.
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VR: Wind velocity at reference height ZR ,10 (m) level above the MSL, m/s
Z: Specified height,
n: coefficient value from 7 to 13 corresponding to the denominator of the exponent, n = 8
may be taken for sustained wind in open ocean.
The wind pressure shall be calculated as:
p    / 2  VZ2 C S
(KN/m2)
Where:
VZ: Wind velocity at specified height Z (m),
: Mass density of air,  = 1.22 kg/m3 for standard temperature and pressure
CS: shape coefficient, CS = 1.0
3.4
Design Summary
3.4.1
Fender Design
The summary of design results for steel wall for fender is listed in Table 4.1. Detailed design
results are found in Appendix A.
The results show that the selected steel wall profile is adequate for use in the KNT platform.
3.4.2
Firewall Design
The summary of design results for firewall is listed in Table 5.1. Detailed design results are
found in Appendix B.
The results show that the selected firewall profile is adequate for use in the KNT platform.
3.4.3
Blast-Wall Design
The summary of design results for blast-wall is listed in Table 6.1. Detailed design results are
found in Appendix C.
The results show that the selected blast-wall profile is adequate for use in the KNT platform.
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
4
FENDER DESIGN
4.1
Design Criteria
KNT-002-TS-ST3-CA-002
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The basic loads used in the design of fender wall include:
 Wind load
Deflections are checked against an allowable deflection of L/240 as per Topside Structural
Design Basis & Design Brief [6].
4.2
Design Results
The results of the fender wall design are summarized below:
Bending
stress
0.11
Table 4.1 – Summary of results – Steel wall for fender
Maximum Uc
Maximum Allowable
Deflection Deflection
Von-Mises
Shear stress
(cm)
(cm)
stress
0.01
0.08
0.016
1.750
Check
OK
The results show that the selected steel wall size is adequate for use in the KNT Topside.
Detailed design results are found in Appendix A.
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
5
FIREWALL DESIGN
5.1
Design Criteria
KNT-002-TS-ST3-CA-002
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The basic loads used in the design of fire wall include:
 Wind load
 Additional fire load
Deflections are checked against an allowable deflection of L/240 as per Topside Structural
Design Basis & Design Brief [6].
5.2
Design Results
The summary of design results for firewall are listed in table 5.1.
Design results of firewall design are found in Appendix B.
Table 5.1: Summary of design results – Firewall
Maximum Uc
Bending
stress
Shear stress
Von-Mises
stress
0.18
0.01
0.12
Maximum Allowable
Deflection Deflection
(cm)
(cm)
0.038
2.167
Check
OK
The results show that the selected firewall profile is adequate for use in the KNT Topside.
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
6
BLAST-WALL DESIGN
6.1
Design Criteria
KNT-002-TS-ST3-CA-002
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The basic loads used in the design of blast wall include:
 Peak blast overpressure - Positive phase = 0.35 Bar
 Peak blast overpressure - Negative phase = 0.00 Bar
 Positive phase impulse rise time = 55.00 ms
 Positive phase impulse plateau time = 0.00 ms
 Positive phase impulse fall time = 55.00 ms
 Negative phase impulse Rise time = 0.00 ms
 Negative phase impulse fall time = 0.00 ms
 Impulse period = 110.00 ms
6.2
Design Results
The summary of design results for blast-wall are listed in table 6.1.
Design results of blast-wall design are found in Appendix C.
Table 6.1: Summary of design results – Blast wall
Maximum Uc
Total Shear
Load
Shear plastic
resistance
Shear Buckling
resistance
(N)
(N)
(N)
72338.9
210798.9
206444.7
Unity
check
Check
0.35
OK
The results show that the selected blast-wall profile is adequate for use in the KNT Topside.
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
KNT-002-TS-ST3-CA-002
Rev.
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APPENDICES
____________________________________________________________________________________
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FIELD DEVELOPMENT, BLOCK 09-2/09
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TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
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APPENDIX A: FENDER DESIGN
____________________________________________________________________________________
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FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
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APPENDIX A - STEEL WALL FOR FENDER
1) Input Data
Calculated width of section of corrugation
p
=
192
mm
Height of section of corrugation
dw
=
59
mm
mm
Actual width of section of corrugation
b
=
257
Thickness of corrugation
tw
=
6
mm
Dimension c
c
=
74
mm
Maximum Wind pressure
Wp
=
3.08
KN/m
Effective bending length of corrugation
L
=
4.20
m
2
Material Properties
Material Grade
ASTM A36
2
Fy
=
E
=
250000 KN/m
2.10E+08 KN/m2
Fb = 0.66Fy
=
165000.0
KN/m
Fv = 0.4Fy
=
100000.0
KN/m2
Fvon = 0.9*Fy
=
225000.0
KN/m
Corrugated Section Properties (Calculated Unit Section)
A = b*tp+c*tw
Section Area
=
19.86
cm2
dW
 3bt p  ctw 
6000
=
49.86
cm3
Z  dW 


10  2 
=
147.07
cm4
Uniformly distributed load
W = Wp *p
=
0.591 KN/m
Maximum bending Moment
M = W*L2/12
=
0.869 KN.m
Yield Strength
Elastic Modulus
2) Caculation
Allowable Stress (Based on AISC ASD)
Allowable Bending Stress
Allowable Shear Stress
Allowable Von-Mises Stress
2
2
Effective section modulus of a corrugation over a spacing p
Z
The moment of inertia
I
____________________________________________________________________________________
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FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
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APPENDIX A - STEEL WALL FOR FENDER
Q = W*L/2
=
Bending Stress
fy = M/Z
=
17430.77
KN/m
Shear Stress
fv = 3Q/2A
=
937.65
KN/m2
2
2
fvon = sqrt(fy + 3fv )
=
17506.26
KN/m2
Bending Stress
Uc = fy/Fy
=
0.11
OK
Shear Stress
Uc = fv/Fv
Uc = fvon/Fvon
=
0.01
OK
=
0.08
OK
1 WL4
384 EI
=
0.016
cm
[f] = L/240
=
1.750
cm
Maximum shear
1.241 KN
Normal stress:
Von-Mises Stress
2
Unity Check:
Von-Mises Stress
Maximum deflection:
Allowable deflection
f 
OK
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
KNT-002-TS-ST3-CA-002
Rev.
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APPENDIX B: FIREWALL DESIGN
____________________________________________________________________________________
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FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
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(FENDER AND FIRE/BLAST WALL)
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APPENDIX B - FIREWALL DESIGN
1) Input Data
Calculated width of section of corrugation
p
=
256
mm
Height of section of corrugation
dw
=
60
mm
Actual width of section of corrugation
b
=
180
mm
Thickness of corrugation
tw
=
10
mm
Dimension c
c
=
106
mm
Maximum Wind pressure
Wp
=
3.08
KN/m
Effective bending length of corrugation
L
=
5.2
m
Yield Strength
Fy
=
250000
Elastic Modulus
E
=
2.10E+08 KN/m2
T
=
2
Material Properties
Material Grade
ASTM A36
Rating of fire wall
Maximum temparature of cold side
2
KN/m
A60
140
o
C
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
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APPENDIX B - FIREWALL DESIGN
2) Calculation
The material properties of structural steel shall be modified for the analysis due to the rise of temperature
in accordance with the equation below as per the API RP 2FB. The thermal coefficient of expansion is




Ts

 yt   y  1 
 767 *ln  Ts  



 1750  

Where:
y
yt
Ts
o
Yield strength at 20 C
Yield strength at elevated temperature
o
Steel temperature in C
o
The equation for the modulus of elasticity at elevated temperature of up to 600 C is calculated by the
following equation:
Et  E 1  17.2 *1012 T 4  11.8*109 T 3  34.5*107 T 2  15.9 *105 T 
Where:
Et
Modulus of elasticity at elevated temperature
E
T
Modulus of elasticity at room temperature
o
Steel temperature in C
The modified material properties in flare boom local in-place design analysis are tabulated in table below:
Modified Material Properties
Temperature
Modulus of Elasticity
at temperature Ts
(x 1000 Mpa)
Elevated
(0C)
Initial Ey
Modified Et
Initial Fy
Modified Ft
140
2.10E+08
2.06E+08
250000
231933.0
Allowable Stress (Based on AISC ASD)
Allowable Bending Stress
2
Fb = 0.66Fy
=
153075.8
KN/m
Fv = 0.4Fy
=
92773.2
KN/m2
Fvon = 0.9*Fy
=
208739.7
KN/m
Corrugated Section Properties (Calculated Unit Section)
A = b*tp+c*tw
Section Area
=
28.6
cm2
=
64.60
cm3
=
193.80
cm4
W = Wp*p
=
0.788 KN/m
M = W*L2/12
=
1.776 KN.m
Allowable Shear Stress
Allowable Von-Mises Stress
2
Effective section modulus of a corrugation over a spacing p
Z
The moment of inertia
Uniformly distributed load (wind load)
Maximum bending Moment
dW
 3bt p  ctw 
6000
I
Z  dW 


10  2 
Q = W*L/2
=
Maximum shear
2.049 KN
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
KNT-002-TS-ST3-CA-002
Rev.
0
Page
22 of 30
APPENDIX B - FIREWALL DESIGN
Normal stress:
2
Bending Stress
fy = M/Z
=
27494.10
KN/m
Shear Stress
fv = 3Q/2A
=
1074.84
KN/m2
2
2
fvon = sqrt(fy + 3fv )
=
27557.06
KN/m2
Bending Stress
Uc = fy/Fy
=
0.18
OK
Shear Stress
Uc = fv/Fv
Uc = fvon/Fvon
=
0.01
OK
=
0.13
OK
1 WL4
384 EI
=
0.038
cm
[f] = L/240
=
2.167
cm
Von-Mises Stress
Unity Check:
Von-Mises Stress
Maximum deflection:
Allowable deflection
f 
OK
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
KNT-002-TS-ST3-CA-002
Rev.
0
Page
23 of 30
APPENDIX C: BLAST-WALL DESIGN
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
KNT-002-TS-ST3-CA-002
Rev.
0
Page
24 of 30
1.0 REFERENCES
The calculations are in accordance with the following references:
1. AISI Manual Cold formed steel specification
2. Fire And Explosion Risk Analysis
3. API RP 2FB Recommended pratice for the design of offshore facilities against fire and blast loading
4. Introduction to Structural Dynamics by John M. Biggs, McGraw-Hill Book Company, 1964
5. EN1993-1-1 Design of steel structures -part 1-1:General rules and rules for building
2.0 DATA INPUT
Blast Pressure
The explosion analysis design report by safety specifies the following blast pressure for the design of Technical room south wall"
Peak blast overpressure - Positive phase
p
=
0.35
Bar = 35 kPa
pn
Peak blast overpressure - Negative phase
=
0.00
Bar = 0 kPa
Positive phase impulse rise time
tpr =
55.00
ms
Positive phase impulse plateau time
tp
=
0.00
ms
Positive phase impulse fall time
tpf =
55.00
ms
Negative phase impulse Rise time
tnr =
0.00
ms
Negative phase impulse fall time
tnf =
0.00
ms
Impulse period
td
=
110.00
ms
Material properties
Grade:
Minimum yield strength
Static yield stress
Young's modulus
Maximum rising pressure strain rates
Strain rate enhancement factors SREF
ASTM A36
Fy
=
Fsy =
E
=
SR =
SREF =
SREF=(1-25/Fsy)+(210/Fsy)*(SR/40.4)(1/5)
Design Dynamic yield stress
0.5
Strain ((235/Fdy))
Fdy
2
250.0
250.0
2.1E+05
2.0E-02
1.083
N/mm
2
N/mm Assumed Fsy = Fy
2
N/mm
-1
Refer [3] table C.11.4.1-2
sec
2
=
270.83
0.9
N/mm
ε
L
tp
bp
=
=
=
=
=
=
=
=
=
5200.0
6.0
180.0
80.0
74.0
112.3
12.0
529.1
41.2
mm
mm
mm
mm
mm
mm
mm
mm
Deg =
30.0
18.7
Class 1
Class 1
Section type and dimensions
Effective Wall Span
Base thickness of profile
Flat width of plane element
Profile depth
Web height
Actual depth of profile web
Corner bend Radius
Width of profile
Angle of web incline to horizontal
2.0 CALCULATION DETAIL
2.1 Classification of section (Table 5.2 of ref [5])
Limiting ratio for
Class 1_Plastic cross section
Class 2_Compact cross section
Class 3_ Semi-compact cross section
Class 4_ Slender cross section (Exceed the limits of Class 3)
Flange section Ratio bp/tp
Web section ratio sw/tp
h
hw
sw
R
W
Φ
Flange
30.74
35.40
39.12
0.72
rad
web
67.07
77.31
115.51
=
=
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
2.2 Effective with of compression flange
Internal compression element
σ1f = σ2f = Fdy =
270.8 N/mmm2
==>
Plate slenderness λp=1.052(bp/t)*sqrt(σ/Ekσ)
Effective width of flange
of 'Z ' section
be1 =
ψ
=
1
kσ
=
4
λp
=
0.57
beff
be2
=
=
180 mm
90 mm
tw
=
9.11 mm
KNT-002-TS-ST3-CA-002
Rev.
0
Page
25 of 30
(Ref.: 2 )
<0.673
=>
ρ=
1.00
2.3 Effective with of the web
Assume the web to be full effect element
Thickness of I-beam web
Effective section properties about y-axis:
Element
L (mm)
x (mm) from
top fiber
Lx (m)
1
2
3
4
5
Sum
169.44
21.57
202.14
21.57
169.44
584.17
77
72.74
40.00
13.74
3.00
206.48
1.30E+04
1.57E+03
8.09E+03
2.96E+02
5.08E+02
2.4E+04
I'y about
own axis
(mm3)
1.00E+06 0.00E+00
1.14E+05 4.09E+03
3.23E+05 7.47E+04
4.07E+03 4.09E+03
1.53E+03 0.00E+00
1.45E+06 8.28E+04
Lx2 (mm3)
L |x-xn|
6.23E+03
7.01E+02
4.09E+03
5.72E+02
6.31E+03
1.79E+04
Distance of neutral axis from top fiber
Xn = LxL
40.24
=
mm
2
2
3.51E+06 mm4
=
Iy=(Lx +'y -xn L)*t
Since the distance of top compression fiber from the neutral axis is more than one half of the beam depth.
The actual compressive will be more than Fy. The compression flange will be yield first
Zp =
1.07E+05 mm3/mm
Web element under new assumed stress distribution
- Compresion stress
2
σ1w =[Xn/(h‐Xn)]*Fdy
=
0.00
N/mm For tension flange will be yield first
σ1w = Fdy
=
270.83
N/mm For Compression flange will be yield first
N/mm For tension flange will be yield first
2
- Tension stress
2
σ2w = Fdy
=
0.00
σ2w =[(h‐Xn)/Xn]*Fdy
=
-267.61
=
=
23.5739
0.233432
<0.673=>
4.29E+04
Nmm/mm width(up to elastic limit)
5.28E+04
Nmm/mm width(up to full plastic moment)
ψ =σ1w/σ2w =
-1 ==>
kσ= 7.81-6.29*ψ+9.78*ψ^2
λp
beff = ρ*bc =
56.5
mm
be1=
22.6
mm
be2=
33.9
mm
8.719E+04 mm3
Weff,CF =
(Elastic Section Modulus)
1.074E+05 mm3
Zeff,CF =
(Plastic Section Modulus)
2.4 Overal longitudinal moment resistance
Mc.Rd = Weff,CF*Fdy*KF*KVM/W
=
KVM = 0.98
Assume KF =
0.98
Mp.Rd = Zeff,CF*Fdy*KF*KVM/W
=
2
N/mm For Compression flange will be yield first
ρ=
1.00
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
2.5 Effective Span
Lower support
(Soft Connection)
Thickness of lower support
Carbon steel grade A36
2
Mc.Rd,L = t L*FLdy/4
tL
FLdy
0
0.0
270.8299
0
100
0
mm
2
N/mm
Nmm/mm width
mm
N/mm
tU
=
FUdy =
=
LUS =
Ksc =
8.0
270.8299
4333.279
100
215.04
mm
2
N/mm
Nmm/mm width
mm
N/mm
=
=
=
5.07E+03
125.1321
0
mm
mm
mm
=
Elastic
67.59
N/mm
=
0.82
N/mm
=
=
0.78
0.81
N/mm
2
N/mm
Effective length
LE = L*sqrt(Mc.Rd /(Mc.Rd+0.5*Mc.Rd,U+0.5*Mc.Rd,L))
LU = (LE/2)*[sqrt(1+Mc.Rd,U/Mc.Rd)-1]
LL = (LE/2)*sqrt(1+Mc.Rd,U/Mc.Rd)-1
Resistance of the wall
Rm = 8*Mc.Rd/LE
Stiffness under Longitudinal bending
3
k= 384*EI/(5*LE *W)
Reduced stiffness (allowing for support bending)
kR = k/[1+1.6*(LL+LU)/LE]
Ksystem
2.6 Natural period
Mass of wall per profile width
Mw = L*tp*LE*7850
Mass of Insulation per profile width
MI = L*tI*LE*130
Total mass per profile width
M=Mw+MI
Natural period
T = 2π*sqrt((M*KLM)/(W*kR))
2.7 Dynamic load factor
Maximum dynamic load factor
(DLF)R= Rm/(Pmax*LE)
Dynamic load factor elastic
td/T
=
1.00
(DLF)E 1.51
=>
Rev.
=
=
=
=
=
LLS
Ksc
Upper support
(Soft Connection)
Thickness of upper support
CarbonCarbon steel grade A36
Mc.Rd,U = t2U*FUdy/4
KNT-002-TS-ST3-CA-002
Ratio Rm/F1
Plastic deflection
td/T
μ= ym/yel (see Figure 2.26 Ref. (4))
yp= μ*yel
tm/td (see Figure 2.26 Ref. (4))
tm
2.9 Shear Resistance of profiles
The relative web slenderness λw = (0.8sw/tp)*sqrt(Fdy/(kτ*E))
Buckling factor for shear buckling
Shear buckling strength fbv
Shear plastic resistance
Shear Buckling resistance
2.10 Shear load of profiles
Distance from the point of zero shear in the wall to support
Maximum shear force
Total shear load
Shear stress in the web
Unity check
26 of 30
Plastic
83.27 N/mm
2
2
=
139.59
kg
=
23.12
kg
=
162.71
kg
=
0.1
Second
=
0.47
Class 1 Cross-section_Rm to be used Plastic
(Detail calculation refer to section 3.0)
2.8 Deflection
Elastic deflection
yel= 8*Mc.Rd/(kR*LE)
Applied dynamic force (blast pressure)
F1 = p*LE
Page
(use J.M Bigs reference)
=
86.44
mm
=
=
177.57
0.469
N/mm
=
=
=
=
=
1.00
1
86.44
0.6
66
at t = 55
elasto-plastic at t = 55
<μ=
msec
msec
4
mm
msec
=
=
=
Vpl.Rd =
Vb.Rd =
0.233
5.34
153.134
210798.9
206444.7
0.6> λw >0.2
Table 7.2, Ref. 2;for no intermediate stiffeners
2
N/mm
N
N
Ls
=
Vmax =
Vtot =
q
=
Ushear =
2662
140.36
74258.2
83.62
0.36
mm
N/mm
N
2
N/mm
<1 Acceptable
kτ
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
KNT-002-TS-ST3-CA-002
Rev.
0
Page
27 of 30
3.0 DYNAMIC LOAD FACTOR (Elastic)
Triangular load pulse to represent blast overpressure
td (sec) =
0.110
tm (sec) =
b (mm) =
Tw (sec) =
0.075
529.1 Width of profile
0.110
ζ=
0.020 damping ratio
tm =
Tw =
time of maximum reaction
Natural period of wall
57.09
57.08
ω (rad/sec) =
td/Tw =
1.000
0.999
Refer to Introduction to Structural Dynamics by John M. Biggs, McGraw-Hill Book Company, 1964. DLF is calculated as equation below:
(with No Damping)
t/td time (sec.)
0.000
0.049
0.140
0.231
0.322
0.413
0.504
0.595
0.685
0.776
0.867
0.958
1.049
1.140
1.231
1.322
1.413
1.504
1.595
1.685
1.776
1.958
2.140
2.322
2.504
2.685
2.867
3.049
3.455
3.818
4.182
4.545
4.909
5.273
5.636
6.364
7.091
7.818
8.545
9.273
10.000
0.000
0.005
0.015
0.025
0.035
0.045
0.055
0.065
0.075
0.085
0.095
0.105
0.115
0.125
0.135
0.145
0.155
0.165
0.175
0.185
0.195
0.215
0.235
0.255
0.275
0.295
0.315
0.335
0.380
0.420
0.460
0.500
0.540
0.580
0.620
0.700
0.780
0.860
0.940
1.020
1.100
Flag1
0
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
DLF max =
DLF =
tm=
DLF
DLF
No
with
Damping Damping
1.26
1.22
0.00
0.00
0.03
0.03
0.15
0.15
0.36
0.36
0.66
0.66
1.01
1.01
1.35
1.34
1.51
1.51
1.39
1.39
0.97
0.97
0.33
0.33
-0.38
-0.38
-0.98
-0.98
-1.26
-1.26
-1.15
-1.15
-0.67
-0.67
0.03
0.02
0.71
0.71
1.17
1.16
1.26
1.25
0.34
0.34
-0.98
-0.97
-1.15
-1.14
0.02
0.02
1.17
1.16
0.95
0.95
-0.38
-0.37
-0.37
-0.37
1.16
1.16
-1.15
-1.14
0.35
0.34
0.70
0.70
-1.26
-1.25
0.95
0.93
-0.98
-0.97
-0.67
-0.65
1.17
1.15
0.33
0.31
-1.26
-1.24
0.03
0.05
1.507
t/td time (sec.)
10.73
11.45
12.18
12.91
13.64
14.36
16.18
18
19.82
21.64
23.45
25.27
27.09
28.91
30.73
32.55
34.36
36.18
1.180
1.260
1.340
1.420
1.500
1.580
1.780
1.980
2.180
2.380
2.580
2.780
2.980
3.180
3.380
3.580
3.780
3.980
Flag1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
DLF
No
Damping
1.26
-0.40
-1.14
0.72
0.93
-0.99
-1.13
0.06
1.19
0.91
-0.44
-1.27
-0.61
0.77
1.24
0.25
-1.04
-1.10
DLF
No
Damping
1.22
-0.40
-1.10
0.72
0.89
-0.98
-1.08
0.09
1.15
0.85
-0.45
-1.20
-0.54
0.76
1.15
0.19
-0.99
-0.99
1.507
1.507
0.08
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
4.0 LOCAL EFFECT CHECK(FENDER AND FIRE/BLAST WALL)
Transverse loading on the profile
External Force
Maximum blast Overpressure Pmax
Dynamic load factor (DLF)
Pressuse P
Pmax =
(DLF) =
P
=
0.035
1.51
0.0527
KNT-002-TS-ST3-CA-002
Rev.
0
Page
28 of 30
Mpa
Mpa =
52.7
kN/m2
Internal Force
Plastic longitudinal strain
εp
=
0.002
Distance from the midline of the compression flange
gw
=
40.239
mm
σ1c =
=
K
Aeff,CF=
Aeff,CW=
Aeff,TW=
Aeff,TF =
N/mm2
Compression flange yielding
N/mm length
to the neutral axis of this section
Compression flange yielding
Factor K
Effective area of compression flange
Effective area of both webs in the compression zone
The area of both webs in the tension zone
Effective area of Tension flange
Compression flange forece FR1
Comprssion part of the web FR2
Tension part of the web FR3
Tension flange forece FR4
Web shear load
Y comp of web shear
(vertical comp. of external + internal load)
FR1
FR2
FR3
FR4
=
=
=
=
270.83
1.00
1146.10
720.08
711.36
1146.10
25.376
7.972
7.970
25.681
V
=
21.406
mm2
mm2
mm2
mm2
N/mm lengt =
N/mm lengt =
N/mm lengt =
N/mm lengt =
25.376
7.972
7.970
25.681
kN/m length
kN/m length
kN/m length
kN/m length
Frame analysis
Analysis of frame undertaken using SACS, on 1m length of wall. Internal, external and web shear loads applied
74
90.0
84.53
90.0
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
KNT-002-TS-ST3-CA-002
Rev.
0
Page
29 of 30
Results
From SACS analysis, the Moment and stress arising from local loading:
|MA| = 157 Nmm/mm length
|MB| = 10.4 Nmm/mm length
|MC| = 91.6 Nmm/mm length
|MD| = 10.5 Nmm/mm length
Axial stress
|σA| = 0.42 N/mm2
|σBW | = 0.42 N/mm2
|σCW | = 0.03 N/mm2
|σDW | = 0.03 N/mm2
δC =
δT =
0.17 mm
0.06 mm
Flange checks
Moment resistance of the plate, Mp.Rd
Mp.Rd =
2437.47
Nmm/mm length
At the web/flange boundary: |MB|/Mp.Rd + |σA|/Fdy
At the Middle of the flange: |MA|/Mp.Rd + |σA|/Fdy
Overall flange resistance check: (|MA| + |MB|)/Mp.Rd
=
=
=
0.006
0.066
0.069
<=1, Acceptable
<=1, Acceptable
<=1.5, Acceptable
Web checks
At the web/flange boundary: |MB|/Mp.Rd + |σBW |/Fdy
At the Middle third of the flange: |MC|/Mp.Rd + |σCW |/Fdy
Overall flange resistance check: ((|MB| + |MD|)/2+|MC|)/Mp.Rd
=
=
=
0.006
0.038
0.042
<=1, Acceptable
<=1, Acceptable
<=1.5, Acceptable
=
1.133
(l=bp)
i
=
for No welding on plating in the buckling zone
φ
=
1.732
Instability check of web and flange
Flange check
Slenderness
λ
𝑙1 𝐹
𝑖𝜋
radius of gyration i = t/3.464
∗ 1
𝐸
ν
The buckling strength, fb
σA/fb + 1.5*MA/Mp.Rd
1.322
χ
=
0.500
fb
=
=
135.28
0.100
N/mm2
<=1, Acceptable
=
0.707
(l=sw)
φ
=
0.825
χ
fb
=
=
=
0.799
216.51
0.057
N/mm2
<=1, Acceptable
=
1.168
(l=bp/2+0.85*sw)
φ
=
1.370
χ
=
0.479
fb
=
129.82
N/mm2
0.13
N/mm
Web check
Slenderness
λ
𝑙1 𝐹
𝑖𝜋
∗ 1
𝐸
ν
The buckling strength, fb
σCW /fb + 1.5*MC/Mp.Rd
Trough check
Slenderness
λ
𝑙1 𝐹
𝑖𝜋
The buckling strength, fb
σ/fb + 1.5*MB/Mp.Rd
∗ 1
𝐸
ν
=
0.00737
<=1, Acceptable
____________________________________________________________________________________
KINH NGU TRANG – KINH NGU TRANG NAM
FIELD DEVELOPMENT, BLOCK 09-2/09
CPP KNT
TOPSIDE STRUCTURE - WALLS DESIGN
(FENDER AND FIRE/BLAST WALL)
REDUCTION FACTOR ON LONGITUDINAL MOMENT RESISTANCE
For cross section flattening (KF)
Using displacement results abtained from the frame analysis.
Effective section modulus of flange W fl.eff.y
Constant based on the section type and class:
The reduction factor KF
W fl.eff.y =
KFC =
KF
=
KNT-002-TS-ST3-CA-002
Rev.
0
79920
0.5
0.999
mm3 For Class 1
For Class 1
167.4
1949.975
3656.204
1.00
Nmm/mm
Nmm/mm length
Nmm/mm length
Page
30 of 30
For Coincident stresses arising (KVM)
|MA|+|MB|
0.8 Mp.Rd
1.5 Mp.Rd
KVM
Check assumption for KF and KVM in calculation
Reduction factor
KF
KVM
Assum.
0.98
0.98
Calc.
0.999
1.00
=
=
=
=
Result
OK
OK
____________________________________________________________________________________