“BENDING MOMENT DISTRIBUTION IN A MARINER CARGO SHIP

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.>
SSC-190
*
c
“BENDING MOMENT DISTRIBUTION IN A
MARINER CARGO SHIP MODEL IN
REGULAR AND IRREGULAR WAVES
OF EXTREME STEEPNESS
m
This
document
for
●
public
has
been
release
and
distribution
approved
sale;
its
is unlimited.
SHIP STRUCTURE COMMITTEE
.
.
SHIP STRUCTURE COMMITTEE
MEMBER AGENCIES:
UNITED
NAVAL
ADDRESS CORRESPONDENCE
ST AT ES COA5T
SHIP
SYSTEMS
GUARD
COMMAND
MILITARY
SEA
MARITIME
ADMINISTRATION
AMERICAN
TRANSPORTATION
BUREAU
OF
TO:
SECRETARY
SfilP
SERVICE
U.S.
STRUCTURE
COAST
WASHINGTON.
COMMITTEE
GUARD
D.C.
HEADQUARTERS
20591
SHIPPING
November 1968
Dear Sir:
A Mariner ship-model study at Stevens Institute of Technology sponsored by the Ship Structure Corrsnitteehaa developed
data to support the measurement of the maximum vertical wavebending moment at the midship section of ships in both regular
and irregular waves.
Herewith is a copy of a report on the
In A lkri%e~
model study entitled ,Bending Moment %skribution
Cargo Ship ModeZ .Tn Reguza~ And Imegulur Waves Of Extreme
Steepness by Naresh M, Maniar and Edward Numata.
to individuals
This report is being distributed
and
roups associated with or interested in the work of the Ship
?!tructure Conmnittee. Comments concerning this report are solicited.
Sincerely,
. ,
QL$*.
D. B. Henderson
Rear Admiral, U. S. Coast Guard
Chairman, Ship Structure Committee
—
—
.
SSC-190
Final Report
on
Project SR-165
“Bending Moment Determination”
to the
Ship Structure Committee
BENDING MOMENT DISTRIBUTION IN A MARINER CARGO SHIP MODEL
IN REGULAR AND IRREGULAR WAVES OF EXTREME STEEPNESS
by
Naresh M. Maniar
and
Edward Numata
Department of the Navy
Naval Ship Engineering Center
Contract Nobs 88263
This document has been approved
for public release and sale; its
distribution is unlimited.
U. S. Coast Guard Headquarters
Washington, D. C.
November 1968
ABSTRACT
An experimental investigation was undertaken to determine
(1) the lengthwise vertical wave-bending-moment
distribution within the midship half-length and (2) the relationship between bending moment and extreme wave steepness, for a MARINERtype cargo ship.
A l/96-scale model was cut to form six segments, which
were joined by a flexure beam. The beam was strain-gaged
to
measure bending moments at the hull cuts at stations 5, 7%, 10,
12%, and 15.
The model was tested with normal weight distribution
and with an extreme “cargo amidship”
loading in both head and
following seas.
The range of regular-wave steepness
(height/
length) was 0.05 to 0.11; the irregular waves had an equivalent
full-size significant height of 39 feet.
Within practical operational limits ofspeed forthe~RINER-type ship, the maximum wave “bending moments in high regular
waves were found to occur in the region from amidship to 0.125L
aft of amidships. Thus the practice of concentrating on midship
bending moments both in design studies and full-scale
measurements appears to be justified for ships of the MARINER-type.
Hogging and sagging moments at any section were found to be generally proportional to wave height, up to a wave-height to wavelength ratio of 0.11, the steepest wave that could be generated.
The bending-moment and wave data from the test in irregular
waves were processed by spectral analysis to obtain equivalent
regular-wave responses. These were ”shown to be, generally, in
good enough agreement with the bending-moment
response obtained
directly in regular waves to inspire confidence in the use of
regular-wave response operators and spectral-analysis technique
to predict the vertical wave bending moment of a ship in irregular-waves.
CONTENTS
Page
INTRODUCTION ...*.... .....*.. ..........................
1
DESCRIPTION OF THE EXPERIMENT .........................
2
...............................
25
SUMMARY ......** ........ *...... .,..*... ....*... ....*..
32
...*... ......* ...........................
32
.*.*.... ...............................
32
..*.*... .....*.. ................ .....
32
ANALYSIS AND DISCUSSION
●
CONCLUSIONS
●
RECOMMENDATION
ACKNOWLEDGEMENT
REFERENCES
●
...**... .....*.. ............................
33
SHIP STRUCTURE COMMITTEE
is constituted to prosecute a ~esearch program to
The SHIP STRUCTURE COMMITTEE
improve
the hull structures of Shfps by an extension of knowledge per’cain~ngto design, materials and
methods of fabrication.
RADM D. B. Henderson, USCG - Chairman
Chief, Office of Engineering
U. S. Coast Guard Headquarters
Captain William 1?.Riblett
l-lead
Ship Engineering Division
Naval Ship Engineering Cet?ter
Mr. E. Scott Dillon
Chief, Division of Ship Design
Office of Ship Construction
Maritime Administration
Captain T. J. Banvard, USN
Maintenance and Repair Officer
Military Sea Transportation Service
Mr. D. B. Bannerman, Jr.
Vice President - Technical
American Bureau of Shipping
SHIP STRUCTURE SUBCOMMITTEE
acts for the Ship Structure Committee on technical
matters by providing technical coordination for the determination of goals and objectives
of the program, and by evaluating and interpreting the results in terms of ship stmc?ural
The SHIP STRUCTUPI SUBCOMMITTEE
design, construction and operation.
NAVAL SHIP ~NGINEERIl{GCENTER
OFFICE OF NAVAL RESEARCH
Mr.
Mr.
Mr.
Mr.
Mr.
Mr. J. M. Crowley - Member
Dr. Wm. G. Rauch - Alternate
J. J. Nachtsheim - Chairman
John Vasta - Contract Administrator
Georqe Sorkin - Member
Harr;son Sayre - Alternate
Ivo Fioriti - Alternate
MARITIME ADMINISTRATION
Mr.
Mr.
Mr.
Mr.
Frank Dashnaw - Member
Anatole Maillar - Member
R. Falls - Alternate
b!.G. Frederick - Alternate
MILITARY SEA TRANSPORTATION SERVICE
LCDR R. T, Walker, USN - Member
Mr. R. R. Askren - Member
U. S. COAST GUARD
CDR C. R. Thompson. USCG - Member
LCDR R, L. Prnwn, USCG - Alternate
LCDR James L. Howard, i.SCG- Alternate
LCIIRLeroy C. Melberg, USCG - Alternate
AF”ERIcANBUREAU OF SHIPPING
Mr. G. F. Casey - Member
Mr. F. J. Crum - Member
NAVAL SHIP RESEARCH & DEVELOPMENT CENTER
Mr. A. E. Stavovy - P.lternate
LIAISON REPRESENTATIVES
NATIONAL ACADEMY OF SCIENCESNATIONAL RESEARCH COUNCIL
Mr. A. R. Lytle - Technical Director, MTRB
Mr. R. W, Rumke - Executive Secretary, SRC
AMERICAN IRON AND STEEL INSTITUTE
Mr. J. R. LeCron
BRITISH NAVY STAFF
Mr. H. E. Ho~ben
Staff Constructor Officer Douglas
Faulkner, RCNC
WELDING RESEARCH COUNCIL
Mr. K. H. Koopman, Director
Mr. Charles Larson,Secretary
LIST
1.
Model
Drawing.
2.
Structural
3.
Weight
Distribution
4.
Filter
Response.
5.
6.
Irregular
Bending
Model
7.
Bending
Model
8.
Bending
Model
9.
Bending
Model
10.
Bending
Model
11.
Bending
Model
12.
Bending
Model
13.
Bending
Model
14.
Bending
Model
15.
Bending
Model
16.
Bending
Model
17.
Bending
Model
Length
18.
Bending
Model
Length
19,
Bending
Model
.
Beam.
Wave
.
.
.
.
,
.
.
.
.
.
.
.
.
.
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.2
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.
. . .
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.4
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.
. 5
.
and
Still-Water
.
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.7
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.9
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.
.
.
.
11
,
.
.
.
.
11
.
.
.
.
.
12
.
.
.
.
.
12
.
.
.
.
.
12
.
Spectrum
Moments
Var~ation
Heading
180
Moments
Variation
Heading
1800;
Moments
Var~ation
Heading
18o
Moments
Var~ation
Heading
18o
Momen’cs
VarJation
Heading
18o
Moments
Variation
Heading
1800;
Moments
VarJation
Heading
180
Moments
Variation
Heading
1800;
Moments
Variation
Heading
1800;
Moments
VarJation
Heading
18o
Moments
Variation
Heading
1800;
Moments
Variation
Heading
1800;
O,.75L
.
.
;
;
Along
Along
.
Moments
Variation
Heading
1800;
.
.
.
.
Model
=
O; Wave
.
.
the
.
No.
the
=
.
.
.
.
.
-.o9
.
Model
Drift;
.
to
.
Length,
Drift,
.
Length
-.09
Model
=
.
.
Length
Length,
Drift,
.
.
.
to
.
Length,
Wave
1.50L
2681-2.
Length
1.75L
Model
2681-2.
0.75L
.
Model
2681-2.
1.00L
.
Model
2681-2.
1.25L
.
.
1.25L
.
.
Model
2681-2.
1.50L
.
Model
2681-2.
1.75’L
.
.
.
.
.
.
.
.
.
.
.
12
.
.
.
.
.
.
.
13
.
.
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.
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.
.
. 13
.
.
.
.
.
.
.
.
13
.
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.
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.
13
.
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.
14
.
.
.
.
.
.
.14
.
.
.
.
.
.
.14
.
.
.
.
.
.
. 14
.
2681-2.
Length,
Model
=
Model
Length
Length,
the
No.
Along
Froude
Model
O; Wave
.
Length
Wave
=
the
Along
Froude
O;
the
No.
.
Length,
Wave
Height,
=
No.
Froude
O;
2681-2.
Model
Length
1.25L
Length
Wave
Length,
Model
=
No.
Froude
1800;
O; Wave
Wave
Along
.
Model
=
2681-2.
Model
Length
1.00L
Length
Wave
.14;
2681-2.
Model
.14;
0.75L
Length
Wave
Length,
the
No.
Froude
.
O; Wave
the
with
.
Model
=
No.
Froude
Variation
.
Along
Model
Length,
to
the
No.
Froude
Heading
.
Along
.13
.15;
2681-2.
Length
Wave
Length,
to
Model
=
No.
Froude
.12
the
Along
.14;
to
Model
Wave
Length,
Model
=
No.
Length,
.14;
to
.13
the
Along
Moments
Model Length,
=
No.
Froude
.13
the
Along
to
Model
=
No.
Froude
,12
the
Along
Froude
;
=
No.
Froude
;
.
the Model
No.
Along
;
;
Bending
Along
Froude
Froude
Moments
1.00L
OF FIGURES
.
.
.
.
.
Model
2681-2.
-.12;
Wave
.
.
.
.
.
.
Model
2681-2.
-.12;
Wave
.
.
Model
Length
.
.
.
.
2681-2.
1.2LjL
.
vi
20.
Bending
Model
Length
21.
Bending
Model
Length
22.
23.
2.4.
;
Froude
.
.
.
.
Moments
Variation
Headinq
180°;
l.75L.
.
.
.
.
.
.
.
.
.
.
Bending
Model
Moments
Heading
Variation
OO; Froude
Along
No.
=
Bending
Moments
Variation
Along
Heading
OO;
Moments
Variation
Heading
OO;
Moments
Variation
Heading
OO;
Bending
No.
No.
Maximum
Bending
WaveHeight/Wave
Moments
Variation
Length,
.05
Maximum
Moments
Bending
WaveHeight/Wave
Maximum
Bending
32.
Bendinq
Station
Moments
~
Bending
Moments
Station
33.
34.
35.
7+
Variat
. .
on
.
.
Moments
10
.
Variat
. .
.
.
.
Bending
Station
Moments
12_$
.
Variation
. . .
.
.
Bending
Moments
.
.
36.
Comparison
37.
Comparison
Weight
on
.
.
.
.
.
.
.
Steepness,
.
.
.
.
.
.
.
.
15
.
.
.
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.
.
16
.
.
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.
.
.
16
.
.
.
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.
.
16
.
.
.
.
.
.
.
.
.
17
Model
. .
.
2681-2.
. . .
.
.
.
.
.
18
.
.
.
.
.
.
.
19
.
2681-2.
.
.
.
.
.
.
2681-2.
.
.
.
.
.
.
.
.
.
.
20
.
.
.
.
.
.
.
.
21
2681-2.
.
.
.
.
.
Model
2681-2,
.
Variation
vs.
Wave
.
Wave
.
.
.
.
.
Steepness,
.
.
.
Responses,
.
with
Encounter
.
.
.
Wave
.
.
.
Normal
Responses,
.
.
2681-2.
2681-2.
Moment
.
Model
Model
. . .
Bending
.
Steepness,
.
.
.
.
15
.
1.75L
Model
Model
15
2681-2.
Model
.
.
.
1.50L
Length
Length,
.
.
2681-2.
Model
.
.
.
1.25L
Length
.
.
2681-2.
Model
.
.
.
with
Wave Steepness,
. . . . . . . . .
of
Moment
.
.
.
1.00L
Length
Length,
.
.
15
,.,.,
2681-2.
Model
Wave
.
.
. . . . . , . . .
Length
Wave
.
2681-2.
0.75L
Wave
Wave
.
.
Wave
.
with
.
Distribution
Bending
.
.
.
.
Moment
39.
.
.
.
.
Bending
Moments
Model
Wave
.
.
.
of
Bending
.
Wave
with
Variation
.
38.
.
.
with
.
.
Wave
.
2681-2.
Length,
2681-2
.
Wave
Model
.21;
.
-.13;
with
Wave Length,
. . . , . . . .
with
.
Model
.
.
.
.
Variat
on with
Wave Steepness,
Model
2681-2.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bending
Station
Station15
.
.
Length,
to
Wave
Length,
Length
.Z3;
Model
2681-2.
-,13;
.
.
with
.
to
Length,
to
Model
.
Length,
Model
.
.
.
.23;
Model
.20
.
.
.22;
to
the
.10
.
Model
.22
Variation
Length,
.
to
the
.07
.
Model
.21
.
Length,
Model
the
=
Variation
Moments
.
Maxima,
Length,
WaveHeight/Wave
31.
Moments
.
to
-.12
.
.20
=
28.
Bending
.
.18; Wave
=
Location
of
.
the
Along
Froude
.
Model
the
Along
Froude
27.
30.
.
=
Bending
-.11
=Drift,
.
No.
.
the
Along
No.
Froude
.
No.
Length,
Drift,
.
Along
Froude
Model
=
Variation
OO; Froude
Model
29.
the
No.
Moments
l-leading
Model
26,
1,50L
Along
180°
Bending
Model
Model
25.
Variation
Moments
Heading
.
.
.
.
.
.
.
.
.
Weight
.
.
.
.
.
.
.
23
.
.
.
24
.
.
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.
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.
.
.
26
.
27
.
.,,.
.
.
.
.
.
.
.
.
.
Distribution
22
25
Cargo-Amidship
.
.
Height,
Frequency,
.
.
.
.
Model
Model
.
.
.
2681-1
2681-1
.
.
.
.
,
.
.
,.
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.
30
.
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31
LIST
1.
Model
Character
istics
2.
Model
-Segment
Properties..
3.
Test
Program
.
.
.
.
.
.
.
.
.
.
.
.
OF TABLES
.
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...3
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...3
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...8
viii
SYMBOLS
h
wave
I
weight
L
model
LCB
longitudinal
center
of
buoyancy
LCG
longitudinal
center
of
gravity
RAO
response
amplitude
operator
s N$%
spectral
densities
of
v/@
Froude
A
wave
height,
crest
to
of
inertia,
moment
length
on
20
ft
trough,
n.
lb-
2
t
stations,
wave
and
moment,
respectively
number
length,
ft
bending
moment
midship
section,
coefficients,
station
10
sag and hog
respectively
INTRODUCTION
In
1960
entitled
bending
Ship
An
the
that
Structure
Moment
moments
midship
of
the
“Bending
in
regular
earlier
pilot
bending
moment
quite
of
authorized
extreme
involving
might
have
in
forms
such
hull
T-2
upper
moments
work
used
tanker
limit
height/length
extreme
as
a
destroyer,
project
was
Project
for
to
sR-157
commercial
be
Since
conclusion
maximum
investigations
extreme
were
calendar
years
Project
1963
sR-165
represent
The
model
for
essentially
of
investiga~inq
reduction
held
together
12$,
and
15,
During
zero
seas.
The
were
performed
0.75
to
The
(])
same
the
to
a
latter
The
program
1.75
in
and
the
conclusions
waves
the
of
the
the
beam
of
and
in
was
moments
extended
in
over
report
ship
It
with
was
experiments.
the
effect
The
the
on
here
of
at
a
to
The
model
strain-gaged
distribution
seas;
tested
the
and
zero
at
normal
be
tested
purpose
a
significant
was
segmented
stations
and
5,
73,
was
tested
at
forward
with
forward
speed
in
speed
in head
seas.
wave-length/ship-length
ratios
investigations
the
waves
study
weight
head
where
cargo
ranged
were
limits
MARINER,
occur
in
the
the
as
ratios
from
0.05
10,
following
The
ranged
to
tests
from
0.11.
follows:
OF ship
speed
in
head
maximum
wave
bending
region
from
amidships
and
moments
to 0.lZ5L
amidships.
Hogging
and sagging
wave
bending
moments
at any section
proportional
to wave
height
-up to a wave-height/wave-length
the
steepest
wave
that
could
be generated.
Ofo.11,
conclusion
program
was
the
reported
loading.
moments.
was
operational
for
it
is
moments.
normal
1963
practical
waves,
regular
and
progress
MARINER
earlier
to
wave-height/wave-length
of
Within
in
was
bending
condition
the
bending
The
a
of
used
speed,
regular
limits
elsewhere,
investigations
cargo-amidship
case
with
drift
that
on
beam.
cargo-amidship
aft
The
wave
model
only,
occur
first
freighters.
design
distribution
The
the
this
moments
at amidships
of about
0.11.
SR-165
1963,the
of
obtain
For
modern
moments
Project
SSC-163.4
extreme
vertical
and
end
was
an
gyradius
the
speed,
following
in extreme
(2)
SR-165
with
flexure
under
to
and
could
by
cargo
1964.
cargo-amidship
m~asure
1963
speed,
for
the
Report
year
iangitudinal
by
At
bending
longitudinal
came
was
of
the
explored
selected
operational
midship
that
and a dry
Ship
Structure
purpose
vessel
circumstances
determining
as
the
and
the
in
1964.
selected
distribution
in
to
presented
work
to
be
tanker,
representative
practical
certain
hull
than
the waves
It was concluded
0.14.”1
limit
of wave
bending
increases
to a value
limited
investigations
and
was
the
weight
, within
under
extended
These
waves.
was
moments
cargo
fairly
no dramatic
upper
wave-height/wave-length
as
this
that
that
is
ships,
expected
known
which
concluded
The
waves.2J3
indicated
should
a
in
MARINER,
program
investigate
steep
of
waves
bending
standard
to
less
ratio
high
midship
a
research
had
waves
in freeboard
and weight
distribution.
covered
those
model
tests,
whose
extreme
a
tests
model
in
vessel,
with
variations
Committee
Project
SR-157
moments
on
model
steepness.
a
an
maximum
bending
different
which
of
calculated
subject
testing
waves
program
theoretically
the
Committee
Determination,”
substantiated
for
(1)
Completion
(2)
Testing
1964
of
of
both
was
the
as
tests
models
the
findings
of
Project
are
generally
ratio
SR-157.
follows:
for
in
the
realistic
cargo-amidship
case
irregular
waves,
in
regular
and
waves.
comparison
of
the
-2results
(3)
with
those
Hypothesizing
the
variatiofl
from
on
of
drift-speed
the
regular-wave
why,
in
bending
case;
and
in
tests.
the
]963 results,
moment along
the
the
DESCRIPTION
a double
reversal
appeared
in
model
length
in the
head
seas,
following-seas
OF THE
forward-speed
case.
EXPERIMENT
Mode 1
The
of
the
tests
standard
These
loadina.
Figure-l
shows
were
conducted
FWRINER,
two
the
model
body
on
with
a
a
65-inch
normal
conditions
plan
and
are
model
(1/96-scale)
weight
six-segment
distribution
and
with
fiberglass
a
2681-1 and 2681-2, respectively.
designated
Tables
1 and 2 contain
the
model
layout;
o
L.\/.L.
10
12
~13
Hull
1
Cut
7
J
L.W.L.
-- ....“,.
——
+_!
I
20
15
20
15
Fig.
1 Model D?awing
dk
12-1/2
~
10
~
7-1/2
Q
5
-—
0
model
cargo-amidship
-3-
TABLE
MODEL
1
CHARACTERISTICS
1:96
Scale
Length
on
Beam,
stations,
9.5
3.47
in,
Beam/Draft
2.72
Block
0.61
Coefficient
Midship
Section
Coefficient
condition
Weight
LCB,
65
in.
in.
Draft,
Model
20
distribution
% ship
Gyradius,
length
% ship
from
~
length
2681-1
2681-2
Norma 1
Cargo
1.44
1.42 aft
aft
MODEL-SEGMENT
2
PROPERTIES
Model
2681-1
A
{
From
~
—&_
1 Actual
(lb
1
-1
{
LC G
I
(in.)
Segment
About
Seg.
LCG
2681-2
A
>
LC G
~
19.5
24.3
TABLE
Model
0.98
in.2)
From
Req’d
I
~
About
LC G
Seg.
(in.)
(lb
in.2)
1
8.04
23.29F
165
1.17
5,33
22.75F
157
2
6.5o
11.95F
38
1.23
4.32
12.06F
35
3
8.17
3-99F
45
1.10
10.63
2.81F
83
4
8.34
3.91A
53
1.32
18.22
3.87A
111
5
7.49
12.31A
39
1.o8
4.45
12.00A
37
6
9.84
22.18A
1.04
5.45
22. 78A
characteristics
and
168
seqment
5, 7*, 10, 12& and 15V
beam,
which
cuts
were
with
vinyl
rubber
to
was
bolted
0.125-inch
plastic
ensure
to
wide
~ro~erties.
The’
aluminum
and
electrical
that
it
se~ments
sealed
tape.
would
not
res~ectivelv.
were
plates
‘joined
imbedded
The
t~gether
in
with
0.008-inch-thick
An accordian
fold
contribute
to
hull
the
was
hull
by
was
an
segment
cut
aluminum
bottoms.
rubber
fixed
put
into
the
stiffness.
163
at
stations
flexure
The
to the
sealing
hull
hull
-4-
Strain
Gages
o
o~
(
Material:Aluminum
A = 1.041’
B =
Fig.
strain-gage
deep
wide;
at
decked
necessary
the
structural-beam
about
the
hull
they
stations
were
of
less
The
the
of
model
to
7-]/2,
10
STN 5 and
and
12-1/2
15
over
except
for
a
for
accommodation
small
of
hatch
in
the
towing
into
parts
center
to
This
be
of
was
in
noise
are
2681-1,
Model
beam
flexures
appreciably
source
distributions
for
six
longitudinal
and reduced
weight
and
a
The
drawing.
The
corresponding
the
to
done
so
six
six
segments
gravity,
and moments
of
inertia
It was possible
to ballast
scale.
the moment
of
inertia
was somewhat
of
the
larger
towing
was
considered
a
part
longitudinal
of
on
gear
the
gyradius
the
over-all
located
ballast
as
in
inertia
the
Model
weight.
of
segment
the
model
immediately
2681-2
was
obtain
of
than
the
vibration
frequency,
to
for
each
part
each
segment
1.5-
0.95-inches
than
model.
weight
inertias
and
larger
In order
Fig.
3.
weight
distribution
The
the
12$
and
fundamental
I aCtual/I requiredis given for each sewen~.
of
sections,
long
larger
than
the
encounter
the
bending-moment
record.
given
in
normal
the
the
Table
2 the
ratio
the
excess
segment
small
the
segment
gear
and
flexure
4-inches
that
of
model
LCG, but
had
were
10,
and
deep
at stations
7+,
beam moment
of
inertia
was made
inertia.
would
be
weight
distribution
divided
ship
model
likely
cuts.
1.04-inches
The
15.
5 and
value
frequency
weight
STN
wiring.
scaled-down
hence
was completely
10 and
12+,
Figure
2 is
centrally
inches
at
0.95”at
Strucihmal Beam.
2
The model
between
stations
located
-’-+
—--t--’
~’-’ie
t--+
and
the
the
ship
The
weight,
was
were
calculated
to
its
required
required.
In
The influence ‘f
was
negligible.
aft
of
ballasted
amidships
to
obtain
as
possible.
Apparatus
The
x
experiment
was
conducted
in
the
Davidson
Laboratory’s
Tank
3
(300’
x
12’
5.5’).
—
-5-
)7
2.5
/1
I
/
I
/’
I
I
2.0
MARINER
I CARGO
MODEL
/
I
I
WITH
AMIDSHIP
2681-2
I
1
I
I
I
I
I
I
I
I
I
I
I
I
I
MARINER
.0006
.0004
0.5
.0002
0
20
18
16
14
12
10
8
~42
STATIONS
STILL WATER
BENDING MOMENTS
MARINER MODEL
\
.0002
.0004
.0006
The
heave,
a
model
and
consisted
by
Weight Disi%but<on ..hdS-k<zlWater Bending Moments.
3
Fig.
heave
was
of a main
mast
to
vertical
translational
had
fore
only
attached
(*6 ft)
surge
and
to
but
carriage
a
towing
apparatus
it
attached
sub-carriage
motion
aft
a
restrained
translational
on
guided
in
to the
the
by
which
roll,
towing
rail.
The
ball-bearing
motion.
The
gave
yaw,
cable.
towing
rollers,
model
it
and
was
freedom
sway.
The
to
pitch,
apparatus
The model
was connected
mast was permitted
only
and the
sub-carriage
attached
to
the
bottom
-6-
of
the
heave
while
mast
restraining
The
model
through
led
a
over
were
pulley
by
The
servo
an
forward
of
system
a
athwartship
speed
falling
fixed
loop,
axis
by
which
applying
weights
to
was
the
at
allowed
the
known
the
end
of
model
The
main-carriage
run ,
of
force
end
model
the
towing
the
at
carriage.
with
the
a
placed
main
matched
automatically
a
was
time
elapsed
6-inch
range
covered
straight-line
11
Bending
The
(the
locations
Gages,
inches
a
to
The
and
model
the
to
string
speed.
station
the
hull
is
the
pitch
the
sub-
which
was
speed,
towing
The
test.
The
1 percent
the
weights
slowed
of
its
cuts).
shown
in
of
the
sketch
surge
model
tachometer
obtained
over
data
points
of
by
of
stations
of
appears
for
the
gages
the
by
5,
on
use
The
~-’
SR-4,
A-19
1.04”
at
stations
7%,
A =
0.9511
at
stations
5 and
10,
and
15
12~
the
flexure
below.
‘.,,
v
B
The
bending
four
strains
gages
only.
together
formed
a
full
Wheatstone-bridge
circuit,
type
7&, 10, 12+, and
----
A =
probe
model.
T
-A.
in
wave-
deviated
calibration.
measured
at
layout
designed
linear
position
strains
which
a
was
and
was
range
measured
A typical
the
the
bending
were
the
by
speed
type,
probe
null
which
apart.
static-calibration
from
beam
over
obtained
average
resistance
than
of
was
20-feet
range.
forward
lengths,
record
The
points
of
determined
in
model
speed
two
was
less
were
four
sub-carr~~ge.
probe
moments
of
measuring
model
in.the
2
moments
gages.
about
wave-amplitude
plot
feet,
was
A continuous
between
wave
minus
located
strain
speed.
to the
2-foot-long
or
amplitude
from
length
constant
fixed
the
The
plus
15
at
use
recording-run
measuring
each
run
with
roll.
accord.
moved with
and a roller,
a
in
the
disconnected
own
pivots
it
was
carriage
controlled
by
T
registering
at
-7-
The
beam,
application
there
was
the
no
five
moment
before
of
of
couples
was
order
to
electronic
filters
amplifiers
and
the
at
moment
the
Each
metal
beam
through
a
introduced
The
was
gages
At
system
noise
the
the
a
of
calibrated
proved
underwent
in
recorders.
15 was
noise.
model,
of
high-frequency
were
pen
the
set
hysteresis.
flexure
minimize
the
high-frequency
of
applied
station
in
moments.
indication
sections
In
installation
known
Because
each
calibration.
adjustable
weights.
only
filter-response
of
the
four
it
curve
is
test
record,
filters
the
least
presented
the
active
available,
to
Fig.
of
carrier
were
likely
in
and
day,
each
A range
of
between
active
was
the
outputs,
bending-moment
circuit,
by
linear
check
in
since
statically
have
start
electrical
unfiltered,
to
experience
4.
ENCOUN” “ER FREQUE NCY RANGE
o
2
4
6
8
10
FREQUENCY
-
12
CYCLES
PER
14
16
18
The
bv Dre/,outputs
20
SECOND
Fi175QP
Response.
outputs
amplifiers
recorded
all
by
six
of
w“ith
a
a
Sanborn
channels
the
strain
carrier
of
qaqes
. -
frequency
pen
writer
information
and
of
on
of
the
wave
24OO
cps
and
chart
were
paper.
recorded
on
wire
4.5
For the
magnetic
were
volts
am~lified
rms.
tests
tape
in irregular
as well
as
paper.
Test
The
test
amidship)
appears
which
and
in
the
program
was
irregular
Table
models
3,
were
composed
wave
which
tested.
lists
tests
Proqram
of
regular
of
both
heading
and
wave
the
tests
models.
speed
of
Model
268I-2
The outline
combinations,
and
were
waves,
on chart
(cargo
of the
program
the waves
in
-8-
TABLE
TEST
Wave
Heading
Heights,
2681-2
Wave
Speed
1.00
5
5
3
5
5
5
5
3
18@
drift
forward
High
Irregular
Waves
for
the
nominal
wave
In
waves
of
h/Lti
0.09.
The
actual
2
18@
18@
Drift
1
2
Forward
2
The
aimed
at
Dalzell.2
the
speed
with
the
applying
The
test
from
the
the
to
term
at
which
reverse
wave
table
1.75L+
waves,
were
were
the
0.75,
refers
Froude
to
number
speed” needs
the
MARINER
wave
-thrust
length.
on
properties
of
below.
the
per-Formed
ratios
1.00,
speed
the
of
1.25,
as
forward,
at
the
qualification.
model
In
drifted
lower
in
1.50,
Runs
1963.
nominal
0.05,
0.07,
wave-maker
appears
speed
at which
the
model
was
established
the
drift
speed
are
listed
to
length
covered
were
the
capacity
of the
,
of
“drift
particular
regular
1.75
terms
was the
Dalzell
1.00L
program
h/Lw
in
of
Zero
test-program
speed
No.
2681-2
Forward
height
to
and
18cP
of
by
2681-1
Speed
lengths
case
Models
Heading
P
covered
1.75
1.50
1.25
5
5
In
Length
5
zero
length
Length/Model
3
.?.
- “
18@
wave
Waves
5
5
in
Regular
5
forward
‘:Tests
in
5
1800
the
PROGRAM
Model
0.75
@
3
wave
0.09,
limited
zero,
head
or
of
length
1.75.
and
the
0.10,
the
drift;
data
to
The
model
ratios
and
wave
but
of
0.11.
height
the
curves.
For each
wave
length,
the
speed
in the
previous
investigation
by
all
waves
of the
same
length
as
run
for
astern
in the
waves
that
speed
highest
wave
associated
was maintained
by
model.
reproducible,
Sea
long-crested
irregular,
State
:
High
7
Average
Period,
sec
12.6
Average
Height,
Ft
26
waves
employed
in
-9-
Figure
spectrum
5
shows
having
the
Pierson-Moskowitz
nations
as
of
1/3
Average
of
1/10
the
measured
same
interim
s~eed
sample.
At
ea;h
sample.
Speeds
the
were
Highest
been
for
was
d~ift
averaged
Heights3
a
‘t
47
of
these
is
included
adopted
in
sea
sufficient
two
run
the
waves;
United
a
for
States
and
to
runs
length
obtain
an
were
taken
of
150
adequate
to obtain
statistic~
an adequate
feet.
ft2-sec
350
l\
l\
PI ERSON
MOSKOWITZ
300
\
/
/
\
A
MEASURED
/
I
250
I
I
I
I
200
;
/
150
I
I
I
I
100
\\
\
I
I
\
/
), ,
\
\
i
I
0
o
\
\
i
I
I
50
0.2
0.4
\
‘L
0.6
WAVE FREQUENCY, RAD/SEC
Fig.
5
Imeguhr
Wave Sp@ctrm.
The
foreign
DENSITY
P,
tz
Pierson-Moskow
comparison.
spectra.
speed,
over
39
height
typical
lenqth
and
‘t
spectrum
wave
has
run
Height~~
energy
standard
forward
Highest
significant
formulation
an
At zero
Average
0.8
1.0
1.2
-1o-
Data
Regular-Wave
The
zero
Test
magnitudes
obtained
by
the
the
of
wave
averaging
speed
speed
Reduction
the
averaging
number
of
heights
data
was
cycles
and
bending
recordeG
for
performed
depended
on
moments
20
feet
for
20
the
model
for
of
cycles
each
model
of
the
speed,
model
time
as
run were
In the
case
travel.
At
history.
noted
in
the
of
forward
outline
which
follows.
Head seas,
forward
Head
drift
seas,
Following
For
waves,
were
These
zero.
Electronic
at
which
when
moments
the
all
5, 7+,
stations
All
the
heights
presented
as
data
were
were
non-dimens
wave
coefficient
p
L
water,
is
irregular-Wave
The
spectra
wave
Associates,
For
the
the
in
moment
and
them
was
quantity
length,
process
dividing
the
B
is
of
by
the
to
, where
for
out
reduction.
lengths,
the
by
eye
The
and
were
non-dimensional
is
model
15,
station
smoothed
pg
maximum
moments,
n-water
moments.
bending-moments
data
wave
converted
pgL3B
bending
sag moments
from
sti
noise
and whipping
noise
in
by
Bending
by
in
records
height
Inc.
was
bending
ionalized
ionalized
model
magnetic-tape
,
and
at
the
moment
amplitude
high-frequency
amplitude.
the
weight
density
beam.
Test
of
output
non-dimens
dividing
the
the
cycles
record
and
12z&. The bending-moment
had a small
noise
content
which
was
10,
steepness.
by
of
the
double
of both
hog and
of high-frequency
made
exclusive
rejected
5-10
speed
maxima
did
not have
a filter,
the
record
was analyzed.
wave
of
f-orward
were
of
were
filters
record
seas,
made
10-15.cycles
speed
measurements
measurements
10-20 cycles
speed
their
form
(hog
operator,
processed
moments,
computation
of
plus
were
bending
tables
~
was
analog
work
center
of
sag),
RAO ,
by
This
in
spectral
,
at
obtained
of
New
wave
frequency
obtain
by
energy
Electronic
Jersey.
SH
The computer
, and
Bending-moment
response
height,
frequencies.
each
to
performed
Princeton,
densities
discrete
at
computer
was
by:
(ft-ton)2
f t2
Bending-moment
frequency
Where
averages
at
each
response,
of
wave
two
of
wave
runs
The
forward
were
(ft-ton/ft
taken
spectral
frequency
spectrally
have
given
KO
was
s
then
calculated
and
plotted
versus
encounter.
were
speed
analyzed,
rise
to
density
calculated.
runs
since
difficulties
in
the
at
a
given
(SN )a
The
following
speed
and
average
seas
narrow
range
in interpreting
to
obtain
a
bendinq-moment
RAO-
was
sample,
spectral
then’
(zero-degree
of
longer
low frequencies
the
results.
two-run
densitv
(~)a/(SW)a
heading)
of
were
encounter
(%
. ,-, .)a‘
not
would
-11-
DAta
Regular
Waves
The
basic
combination
curves
of
for
model
variation
the
These
graphs
and
data
of
along
P5
Presentation
hull
in
and
wave
in
the
length
L
coefficients
.
@sag
of
for a series of constant values
in
verSuS
B
speed,
bending-moment
length,
appear
268I-2 at-bpresented
Model
heading,
6
Figs.
h/L
to
26,
with
the
exception
form
of a graph
for
each
Each graph
shows
the
and
wave
of
Whog
(v=mo~~;t/pgL’B)
steepness
.
Fig.
14,
which
shows
.
h
It
is necessary
moments and
moment
that
to
the
bear
mind
in
origin
of
the
that
!+
graphs
is
and
the
refer to dYnamic bendi:9
~h
still-water,
zero-speed
MODEL,
?601-2
MODEL
WAVELENGTHS.
MDDEI.
,—
.0018
—
—–
SPELO,
——
.
,.
—-----
hl~
..—
.
.ly*---
~
‘3/3
----
l+J-
‘“
‘
093
/
000R
x
0006
.CO06
—
‘
‘
#-
--%
hli,
.<<
--””
h /A
0“
_
/
A ~’
/’
0004
-—
,1
,/
:
!,
‘004
HA%3:’-
.-
,’
,/’
,m
09(
=
-,
C
,.‘“=”’
hli
f
.. .
.0010
‘“
.14
., .
----
0012
.0012
.
“.-
‘mm
0008
NG_,!”H:m
.~.
—
0016
---
.0010
~EAol
v/~L
Oole
. .-
0016
0014
bending
(Fig. 3).
.,
.“,
083
“—
.*
.Ubl
-—c
L
,
\\
—“
\
--..,
‘/
‘
\
D——
/)
‘
,
‘~ -..
‘\
nl>7
\
\
,/<)
>
.-
.0002
0002
3TATION3
,0
,;!
15’,
,1
5
0
*
0002
,
c>
<,-
.
\:-0004
0004
.0006
0006
. .
,r
\
\
\
—
1
‘.
<“./’
n67
////
~.i
_
~,/;
0010
0012
.0012
0014
0014-
Vmiation Along The
F;g.
7
“
h/i:
.083
L
w“
/~
0010
y
/’
h 1>
x’
‘“”’t-ttmti
Fig.6 Eami-in Momm-k
Model %zgtlz.
01t7
=
\.
‘\,
0008
h/J
,( )/> ~
., .“-----
~
lb/).
=
.09L,
.108
.Bend{n Moments VariationAZong
l?l-w
lb3aZ Length.
1
-12MODEL,
WAVELENGTH
MODEL
Fig.
8
~
~,
MODEL,
MQDEL
sPEED,
ulfiL
HEAOINGJJR.
=~
Binding Moments Variat{on Alozg
The Mode2 Length.
MODEL,
wAVELENGTHJd5L,
MODEL
~
9
~
,
MODEL
MODEL
5PEE0,
MODEL,
Vl~L
HEADING*
=&o
MEnD, NG_.
v/&L
=-o
.)4
Bending Momants Variation Along
The ModeZ Leng5h.
~
MODEL
SPEkl),
WAVELENGTH
IS
2681-2
wAvELENGTH~,
.III
MOOEL
MODEL
SPEED,
HEAOING~
u!&L
=~
.001,
.00(6
0014
.00,2
1
1
I
I
I
!
!
I
I
“tL&E%
I
,0002
1/,”
I
f.-+-
—.L.i.
7 hlA
.050
,T*T,
15
0
Fig. 10 Bending Moments Va~iatizons
AZong The ModeZ Length.
1
1,4
ON*
10
~+
‘--=:
1
11 Bending l.umentaVa~iation Azong
The Model Length.
-13-
_
MOOEL
,
MODEL
MoDEL,
~
MODEL,
WAVELENGTH
sPEED,
wAvELENGTH
HEADING%
vl@
MODEL
‘~
,00!,
,0018
0016
0016
om.
0014
.0012
,0012
0010
00,0
.000.
Oooe
0.00.
.0006
.0004
000,
~
MODEL
SPEED,
“lfiL
HEADING?
,~
.0002
0002
0
0
0002
.0002
.004
0004
,000.
.0004
Oooe
0000
Fig.
s,
00,0
0010
0012
00,?
004.
0014
12 Bending Mom@nt Vcmiak<on A20ng
The Mode2 Length.
MODEL,
kq
13
.
Bmdinq Moments Vmiation AzOng
The Mo&Z Length.
&
WAVELENGTH—,
MODEL
MODEL,
HEADINGS
WAVELENGTH~,
MoDEL
SPEED,
v!m
1MODEL
HEADINGLBY
.L
MODEL
.00!8
SPEKD,
v!fiL
‘1
0018
00,6
.Oolc
0014
00,,
00!2
0.,,
.00(0
00,.
<
<
000.
0000
0006
0006
,0004
0004
.0002
.0002
0
0
,0002
.0002
000*
0004
,000.
000.
<
0000
.0008
.00!0
Oom
.00,2
0012
.0014
00,.
Fig. 14 Bend<ng Moment VcwtationWikh
Wave Height.
Bending Moments Variation
Along The Modal Length.
-14MODEL,
Wavelength
MODEL
Fig.
16
MODEL,
~
U4,
MODEL
SPEED,
Vl&L
MODEL,
MODEL,
MODEL
MODEL
SPEED,
“l&L
HE bDtNG~
=%,
‘.09
to
-.12
17 Bending Moments Va~iation Along
The Model Leng-th,
~
wAVELENGTH~.
,
MODEL
W-
Bending Moments Variation A20ng
The Model L@ngt/i.
L6~
WAVE LEF4GTH~
HEADING=
HEADINGA.
WAVEL<tiGTU~,
MODEL
~
MQDEL
SPEED,
v,&L
HEADING=
.
Drifr
.oo14LLL—kL!!LLl_Lu—.—l
,00,2
,00,0
<
000B
.0006
0004
.0002
0
.0002
0004
,0006
<
0008
/
I
h/ ,-.1
0
00,0
,0012
18
Bending Moments VariatfonAzong
The ModeZ.L@zgth.
19
Bending Momen-& VariationAZong
The Model Length.
-15MODEL,
MODEL
MODEL,
.@k,L
WAVELENGTi4~,
MODEL
..—
5P<E0,
vL~L
= Ur~+t,
II
m
I
I
I
I
I
MODEL
MODEL
-.1?
SPEED,
HEADINGK
v1&L
.~
. . IZ
tO
. . II
,0018
00, s
0016
~
WAVELENGTH~,
HEADING=
I
I
—
.00I*
00,4
0014
00(2
,00,2
00!0
00,0
<
0008
0008
0006
0006
0004
000.
000,
0002
0
0
,002LLLLJ-
! !..4-4 I
.0002
0004
000.
<
.,
“:m+
0006
0000
00(0]+,--, ‘i
I I I I
I
I
00,,
00(0
I
I
I
I
00,2
.00(,
Fig.
.001”
20 Bending Momw+s Vaxiat-ion
Along The Model Length.
MODEL,
WAVELENGTH~,
MODEL
~
MODEL,
MO,DEL
SPEED,
Fig. 21 Bending Mom@n-LsVariationAlong
Th@ Model Length.
vl&L
HEADINGX
~
WAVELENGTH~,
.JJ_
MODEL
001 n
MODEL
SPEED,
“/fiL
HE ADINGLe
.~
,22
‘“”~
0.,6
..,6
00!4
00!4
.00(2
0012
.0010
0010
<
0000
Ooot!
0006
0006
0004
.0004
0002
“1
000,
.000,
/4!!:1°’>1
,.&w
L“”+*<
.
/“
h/A
.0006
.0002
,—.
.091
0008
.
*
00,0
llllll\
h ,’).=
.0 99 ~
I
000.
00,0
00!2
0012
Oo,.-
Fig.
22 Banding Moments Var<ation
A20ng The Model Length.
Fig.
23 Bending Moment Variation
Along the Modal Length.
-16MoOh L,
WAVELENGTH
~,
MODEL
~
MODEL
SPEED,
,/fiL
r,40DEL,
HE AOING~
.~
WAVELENGTH
.23
~,
MoDEL
~
MODEL
SPEED,
v&@
HE AD(NG~,
.~
,zj
0018
00,6
0014
0012
0010
,0008
0006
0004
.0002
,0002
,0004
\
I
Fig.
24 Bending MomaztisVariation
Along The Model Length.
MODEL,
wAvELENGTH~,
MODEL
~
MODEL
SPEEO,
25 Bending Momen-k Vcu%ation
Along Tha Model Length.
vl&L
HEADING_Q_a
.-O
.21
.0016
Oola
.001.
00,,
.0010
.
4
.000.
0.0.
.0004
0002
0
0002
.0004
,000.
0000
.0,0
.0012
.m.
Fig.
26 Bending Moments Variation
AZong Xhe Model Length.
2681-2
MODEL
L = h/A < 0.07
H = hlk > 0.07
o
!
1.,75
A.
●
0.75
I.oo
A
●
--+
o
+
A
●
1.25
o
+
A
1.50
1800 Heading,
+
-
Fwd
Speed
0
-t
A
Drift
0°
Fig.
Figure
during
h/k
=
each
0.05,
respectively.
Z7
Fwd
Speed
O
27 Eoeak’ionOf Bending Momen_& Maz%ma.
shows
different
0.07,
Heading,
.
the
location
condition
and
0.10,
the
of
bending-moment
of heading,
values
of
maxima
speed,
and
maxima
appear
the
hull
wave
length.
in Figs.
z8,
along
For
29,
length
con$tant
and 30,
Model
BOTH HEADINGS
2681-2
AND ALL
SPEEDS
*.-. ,,-!
.Uul(
‘ave
Wave
‘e;qht
Length
=
.05
.001[
.ool~
.0012
.0010
.0008
*
.0006
o
e
1 .25L
1 .50L
.0004
.0002
.75L
] .00L
] .75L
[
WAVE LENGTH,
.0002
o
o
A
.0006
0
A
.0004
●
L
☞
☞
●
✘
A
+
☞
●
●
.0008
.0010
Fig.
28
Mcmim
1800
Heading,
Fwd
1800
1800
Heading,
Heading,
Zero
Drift
Speed
00
Heading,
Fwd Speed
Speed
speed
●
+
A
o
Bending Moments Va~iation With Wave L@zgtk.
2-OOL
-19Model
BOTH HEADINGS
2681-2
AND ALL
SPEEDS
.0018
‘ave
Wave
‘eiqht
Length
.07
=
.0016
.0014
+
.0012
.0010
●
●
A
o
.0008
.0006
_
.0004
!
.0002
I .00L
,75L
1 .25L
1 .50L
1 .75L
0
1
WAVE
.0002
LENGTH,
o
$
0
0
0
.0004
0
A
A
.0006
k
+
●
A
+
$
●
.0008
●
●
.0010
Fig.
.—
—
29
1800
Heading,
Fwd
1800
Heading,
Zero
Speed
Speed
m
+
180~
O
Heading,
Heading,
Drift
Fwd
Speed
Speed
A
O
Maximum Bending Moments Vmiation With Wave Length.
-20Model
2681-2
BOTH HEADINGS
AND ALL
SPEEDS
.0018
Wave
Heiqht
Wave
Length
=
.10
A
+
.0014
●} M
+
A
●} X*
o
0
*
o
●
.0010
$
8
.0006
.0002
.75L
] .00L
1
I .25L
I .50L
I
WAVE LENGTH,
k
.0002
:
i-
0
0
.0006
+
●
A
.0010
Fig.
30
Maxim
1 .75L
A
1800
Heading,
Fwd
1800
Heading,
Zero
1800
Heading,
Drift
0°
Heading,
Fwd
Speed
●
Speed
Speed
Speed
i
o
Binding Moments Variation With Wave Length.
-21-
Model
2681-2
Station
BoTH HEAOINGS AND ALL
WAVE
5
LENGTHS
AND
SPEEDS
.0018
.0014
I
am .0010
F
.0006
.0002 I
.0006
*z
1800
.0010
Head ins.
“;
0°
Heading,
Fwd
zero
Drift
Speed
Speed
Speed
.
+
A
Fwd
Speed
o
I
Fig.
For
points
31
over-all
each
through
35).
the
of
an
of
four
the
speed
basic
data;
case.
31 Bending Momentis Va~iation With Wav@ Steepness.
view
of
bending-moment
test
station
are
Four
different
plotted
symbols
trends
with
on a single
are
used
to
heading
and speed
conditions.
one
includes
all
the
data
and
Two
one
wave
graph
of
distinguish
envelopes
excludes
data
height,
1A
are
of
all
versus
between
drawn
the
the
h/1
data
to
the
head-seas
data
(Figs.
for
scatter
forward-
-22-
2681-2
Model
7+
Station
BOTH HEADINGS ANO ALL WAVE LENGTHS AND SPEEDS
-001
.001
.001
.000
.+
.OOOi
o
+9
.08
-04
I
1
.12
I
h/X
I
I
I
I
I
.0002
.0006
.0010
1800
0°
Head ing,
Heading,
Fwd Speed
Zero
Speed
Drift
Speed
Fwd Speed
●
☞
A
o
.0014
32 Bending Mom@nts Vcu-iatioti
With
which
The data for
were
obtained
the
in
head-seas,
1963
the
zero-speed
tests, are
case
reproduced
in
wave
lengths
1.00L
to
from
Reference
4.
1.75L,
-23-
2681-2
Model
Station
BOTH
HEADINGS
ANO ALL
10
WAVE
LENGTHS
AND
SPEEDS
.CIO18
.0014
.0010
5
WI
.0006
‘~
o
.0002
.08
.04
I
.0002
0:
hll
.12
I
I
I
I
I
0
.0006
I
3
.00[0
1800
0°
Head ing,
Heading,
Fwd
Zero
Drift
Fwd
●
☞
Speed
Speed
Speed
Speed
A
0
.0014
Irregular
Waves
Curves
the
energy
Superimposed
data.
These
of
bending-moment
spectra
have
been
on each
plot
are
points
represent
response
charted
(~on
a
,
base
bending-moment
the
sum of hog
of
ft-ton/ft)
wave
response
and sag
which
frequency
points
moments
were
of
derived
from
encounter.
from
regular-wave
divided
by wave
test
height
-242681-2
Model
Station
BOTH
HEADINGS
AND
ALL
12+
WAVE
LENGTHS
AND
SPEEDS
.001/
.00IL
.0010
5
m
.0006
-0002
.04
I
.08
I
I
.12
i
I
hlk
I
I
I
I
o
.0002
0
.0006
5L
.0010
180° Heading,
Fwd
,
0°
Heading,
Spee
>
4
Zero
Speed
+
Drift
Fwd
Speed
Speed
A
o
.0014
at
h/A
te5t
=
0.08
.
range
of
wave
condition
stations.
Bending Moments VaPiation With Wave Steepness.
34
,F{g.
2681-1
This
height/length
steepness.
and
2681-2,
Figures
respectively,
ratio
36
was
and
chosen
37
within
as
present
a matrix
being
all
in
such
of
the
middle
plots
speeds
and
for
hull
of
model
the
.25-
2681-2
Model
Station
BOTti HEADINGs
15
AND ALL WAVE LEt4GTHs AND smEmi
.00IE
.001
+
m
5
+
.001
/
● e‘P
+
*
+
!$
++*
‘
●oem
A+
●
+tA
o
I
h/L
.12
.08
.04°0
I
I
1
●
&o
●
●
,
%
f
●
o
Q+
++A;~#
/
.00
,4A
#’%o~
/
+
.00
-1
+4
I
I
I
1
I
\
.00
‘---
r
.00
3
.00
1800
0°
Heading,
Fwd Speed
Zero Speed
Drift
Speed
Fwd Speed
Heading,
●
+
A
o
.001
Fig.
Bending Moments Variation With Wave Staepnasz.
35
ANALYSIS
The
case;
(b)
distribution;
and
(d)
regular-wave
comparison
(c)
comparison
data
of
are
model
comparison
between
discussed
with
of
cargo
station
regular-wave
AND
in
DISCUSSION
the
following
amidship
10
and
data
and
for
sequence:
model
this
irregular-wave
with
test
and
data.
(a)
normal
Dalzell’s
cargo-amidship
weight
test;2
-26—
Derived
from
Spectra
Regular
Wave
Re5ult5
froIIl
Irregular
WaVC Tests
Hog + Sag
Htight
ft-tOns/ft
wave
v/&L
V/a
= .12
,ta,~
“/.&
= o
~
i-.
ll
Ifl,
J’? k Y
J“(/) r,
S.12.5F
r
1P
,ta.l,~~ y
1.0
.5
.5
Frequency
Fig
The
measured
coefficients
are
moments
shown
1.0
T@r,
are
dynamic
The
moments.
15
Normal-weight
static
a
wave
standard
moments
L/20
0.00047
0.00043
hog
hog
hog
calculated
wave,
Speed
various
range,
and
combinations
the
location
of
speed
7$
0.00040
0.00039
without
and
and
Weight
wave
model
and
for
0.00059
0.00029
hog
0.00007
sag
sag
correction
sag
5
0.00013
0.00053
sag
0.00078
are
Cargo-Amidship
for
moment
hog
sag
in
bending
10-(1)
12+
0.00004
amidship
The
still-water
0.00022
distribution
midship
1.0
.5
radl~ec
below.
Station
Cargo
encOUfi
Compczx=ison
Of Bending Momenk Responses
Nomal Weight Distiibutiion.
36
.
of
Smith
hog
effect,
at
hog.
Distribution
length
direction,
in
which
the
are
plotted
maximum
in
moments
Fig.
occur
27.
—
-27—
.
.
Derived
from
Spectra
Regular
Wave
Results
Hog + Sag
= .12
“/&L
Tests
..
k
v/a
= o
.k IL
..
7.5
Sta.
wave
.
i!!
IL
..
5
5ta.
I rregular
18@ Head Seas
Height
$t-t0n5/ft
Wave
Sta.
from
10
PIL
.
.“
Sta.
12.5
I!EIL
“.
Sta.
15
Frequency
37
Fig.
is
lt
and
14
the
more
important
18
to
severe
of
the
be
maintained
to
knots
in
sea
MARINER
is
in
recognize
that
following
such
that
only
n the case
of head
ng
are
moments
are
ocated
Figures
that
the
wave
maximum
A complete
wave
set
In
the
of
cargo-amidship
which
noted.
it
proportional
are
can
to
the
the
be
seen
wave
the
maximum
in
zero
to
in
to
!1
speed
shown,
for
the
and
head
seas
realize
horsepower
speed
drift
both
at
speeds
hog-
all
do
1.75L
in
could
five
and
on
with
“it
may
coefficient
the
report,
normal
only
purposes.
sag-moment
locations.
appreciably
Generally,
bending-moment
the
waves,
maximum
the
$ogging
27).
vary
heading
in
The
wave
be
said
lengths.
reportq
present
short
12+.
speed.
wave
of
the
not
zero
180-degree
attainable
relatively
Fig.
(see
illustrative
the
in
Il&
at
to
in
for
speed
11 and
curves
presented
is
that
test.
knots
for
the
ship
The installed
stations
moments
except
1.25L
streamlining
trends
forward
10 and
of
height
at
showing
was
only
the
of
between
1.00L,
charts
case
of
9
impossible
conditions
seas
occur
interests
representative
speed,
that
ratio
of
speeds
be
during
stations
above
moments
height/length
tion.
the
show
lengths
the
located
between
2~-30
for
1.0
.5
rad/sec
waves.
sagg
length
would
simulated
steepest
moments
en.ountcr,
forward
waves
maximum
Except
of
Comparison Of Bending Momant Responem
Ca~go-AmidshipWeight .Distpibution.
conditions
the
1.0
.5
1.0
.5
at
highest
waves,
coefficients
An
on~
Figure
zero
alternative
versus
weight
such
14
speed
distribuchart
for
is
and
drift
as
previously
are
roughly
interpretation
is
-28-
that
there
is
no
Generally,
In
moments.
when
added
the
to
Figures
figures
of
at
occur
speed.
In
forward
forward
to
and
zero
speeds
zero
hogging
collected
stations
in
of
Results
maximum
An
not
examination
of
necessarily
always
Gross
other.
appears
“x,”
models
estimate
against
means
that
the
the
station.
10,
the
and
15
they
moments
of
the
to
the
maximum
at
magnitudes
in
than
sagging
found
conclusion
moments
the
Four
head
seas,
highest
moment
smaller
These
in
in
are
similar
highest
significantly
Weight
Normal
data
the
for
larger
of
test
which,
moments.
that,
occurs
the
in
zero
occur
if
at
the
zero
drift-speed
the
case
case
of
forward
seas.
for
the
each
hogging
present
sagging
and
leads
head
large
12~
the
not
dynamic
are
7+,
then
(Magnitude
are
5,
stations
This
are
v~ry
at
seas.
head
the
moments
the
magnitude
of moments
The
largest
moments
occur
unattainable,
be noted
that
case
speed
Comparison
data
glance
moment,
in
considered
it
should
in
a
at
bound.
than
sagging
the
while
upper
larger
result
speeds.
of
an
are
moments,
at
speed,
reach
still-water
combinations.
At
zero
case
following-seas
and
all
compare
the
speed.
high
present
to
to
moments
sagging
forward
and
speed
35
or
speed
is
However,
the
area,
speed-heading
at
moments
sagging
dynamic
forward
moments
at
the
intended
conditions
for
dynamic
midship
31
are
mostly
tendency
the
or
tendencies
model
are
of
and Cargo Amidship
of Moments)
two
models
smaller
is
which
moments
Distribution
reveals
for
one
summarized
has
the
the
same
below
larger
that
in
model
in
moment;
magnitude,
or
the
dynamic
comparison
table
moments
with
form.
the
A mark,
an
“x”
against
do
not
show
both
a clear
tendency.
MAXIMUM
Heading
& Speed
180°,
+
{ Cargo
amidship
]8cf,
Zero
x
Norma 1
Sag
{ Cargo
The
hogging
cargo-amidship
higher
case
has
case.
with
of
P,
Fwd
x
x
x
x
x
x
amidship
moments,
associated
Drift
x
weight-distribution
cantly
1800,
Norma 1
Hog
waves
station
r-d
MOMENT
and,
the
total
h/h =
10 are:
Since
furthermore,
0.10
cargo-amidship
moment
,
at
than
drift
x
generally
larger
dynamic
since
there
distribution,
does
speed
a
sagging
sagging
normal
in
head
moments
is
a
large
moments
are
the
moment
the
than
still-water
such a loading
weight
distribution.
seas,
than
larger
normaldynamic
sagging
results
in
a
Imoment
signifi-
For
example,
coefficients
at
in
-29-
Normal
Hog
Highest
dynamic
Still
water
Tots
hog
Although
two
plus
the
than
the
total
0.00047
0.00047
0.00053
0.00053
0.00134
0.00080
0.00030
0.00183
and
is
speed
Model
maxima
stations
models
to
loss
of
remain
Comparison
(a)
than
(b)
For
6 percent
and
deviations
in
(c)
in
comparable
which
is
for
the
one-third
larger
reflected
in a reduced
pitch
radius
of easing
pitching
and heaving
architect
this
type
maxima
and
of
around
ship
operator
loading.
station
10 and
hogging-
2681-2 had sagging-
Model
length.
Results
moments
and hogging-moment
maxima
for
both
of
the maximum moments
However,
quarter
10
bending
the
two
groups
one
with
satisfactory
with
at
Results
station
of
test
and
seas
were
drift
12
of
of
10 with
results
is
10
percent.
hogging
speed.
Reference
Dalzel
2
l’%
midship-moment
consistently
of
ten
higher
following
was
seas,
ten
or
the
In
following
two
tests
that
instrumentation,
the
out
less;
Visual
comparison
sagging-moment
in
curves
Dalzell
’s
have
of
21
or
lower
comparable
speed
were
people,
the
slopes
generally
the
results
are
slightly
Regular
and
Irregular
is,
if
the
of
sets
at
the
of
zero
speed,
average
performed
on
results
show
slopes,
higher
percent.
of between
Average
corresponding
same
speed,
7
was
differences
forward
comparison
zero
deviation
twenty
of
between
Average
at
was
16 percent.
speed,
6 percent
at
sets
of
percent.
showed
different
of
comparable
differences
average
six
seas
under
by
twenty
showed
speed, 6 percent
forward
moments,
considers
slopes
out
less;
deviation
at
percent
different
reported
curves
while
than
different
the
those
in
the
here.
Comparison
superposition
maximum
percent
In
6
six
or
and the
maximum
deviation
were
10 percent
at
forward
seas
drift
the
ship-wave
length
the
13
of
percent;
at
hogging-moment
[-F a
percent
speed.
case
head
moments,
6
of
agreement.
that
sagging
differences
was
If
of
percent;
the
3 percent
deviation
Fixed
sagging-moment
are
Thus,
any tendency
to
from
the
~oint
of view
of
naval
of
--
moment
--
case
12
For
and
results
wave
head
showed
percent
shows
the
O* respectively.
differences
at
deviations
models
which
is
effects
effects
Station
case.
undesirable
Clearly,
midship
sag
sag
loading
beneficial
12&
the
of
of
the
percent
results
and
had
ion
stal
and
that
showed
6
the
plus
total
other.
results
and
of
Neither
the
have
hog
a
tendency,
conflicting
within
indicates
total
has
appears
,,
a
n waves.
the
Comparison
results
0.00213
normal
such
2681-
around
11*
the
amidships
known
cognizant
Whereas
moment
around
the
near
-case
of
However,
reducing
be
ranges
moment
loads
loads.
gyration,
must
6
0.00130
cargo-amidship
hog
concentrate
‘bending
of
0.00083
0.00214
bending-moment
the
sag
0.00127
sag
loadings,
Loading
Sag
Hog
0.00087
]
Total
Cargo-Amidship
Loading
is
system
proportional
may
be
applied.
Between
is
linear,
to
that
wave
amplitude,
The principle
may
ship
Wave
motion
Data
amplitude
then
the
principle
be
stated
as
follows,
of
in
waves
of
linear
according
to
-30-
2681-1
Model
Station
180°
Heading;
5
v/ti=
.12
-
.14
kIL
= 1.25
,@
‘h + ‘s
/
0’
,’
.0015
1.00
75
.0010
.0005
0
I
I
I
1
1
.02
.04
.06
.08
.10
IIIL
Fig.
E
V.
Lewis:5
1 near
“ The
summation
tl 5 sea
respective
and
In
the
testing
(a)
the
measured
the
36
sources.
two
in
is
regular-wave
augmented
was
range
nearest
(sag
to
the
an
irregular
sea
components
of
in
regular
37
tests
the
to
plus
the
hog)
waves
quotient
show
that
Only
at
can
the
there
region
at
5
derived
spectrum
the
4).
38
h/L
;
defined
Fig.
5.
by
the
of
their
““
is
relationship
divided
by
wave
at
slamming
curves
show
results
speed
is
detected
at
of
the
explanation
therefore,
particularly
response
spectrum).
forward
were
curves
method
implicit
equals
between
possible,
presents
these
A common
A possible
and
have
functions
spectrum
loading
a
components
by
tested.
agreement
normal
manner,
Figure
versus
It
The
wave
difference.
non-linear
represented
response
from
times
emergence
2 and
a
and
ship
reasonable
for
significant
of impact.
station
is
5
forefoot
in
applied
compare
(b)
be
sea.”
condition
in regular
waves
linear
with.
wave
height.
function
(response
References
moment
be
to
and
station
significant
(see
bending
can
is
(response
a consistent,
case,
of each
loading
are
reasonably
principle
applicability
the
and
there
this
tests
which
of
obtaining
the
36)
ship
to
principle
Figures
(Fig.
a
superposition
degree
directly
by
that,
of
responses
instance,
results
superposition
spectrum)
from
its
the
linear
summation
of ship
responses
are
each
energy
spectra,
for
example
the wave
spectrum
of
Accordingly,
in
response
of
the
present
bending-moment
yielded
of
Bending Moments Variation With Wave Height.
38
in
that
station
slamming
5,
bending-moment
pronounced
the
which
-31-
non-linear
that
trends
the
by
spectral
in
rough
wave
of
points
at
a moderate
results
are
from
To
h/k
of-
0.05
on
Fig.
irregular-wave
In
seas
range
Reference
at
distributions
distinct
4
drift
(see
and
7+
approaches
whereas
in
the
cases
different
values
as
well
as
its
12*,
trends
to
with
the
data
be
From
in
0.08, which
of
Fig.
38
These
curve
shown
Fig.
is
36;
clearly
forward
at
this
wave
normal
The
weight
speed,
curves
behavior
moment
and
along
sagging
model
distribution,
experienced
were
remains
bending
hogging
location
Length
characterized
for
both
moments
length.
2681-1
5
v/@=
Head i~g;
.12-
.14
Rrgular
D
,\,
/’
/’
h/),
=
.08
“.!
‘0
d
“
Waves
.
/,
,/m’\
l’” ,/
h/i.
=
.05
‘{
‘*
j“
f From
spectrum
analysis
:/
/.%
$“
&,
I
I
1
.4
.6
.8
Wave
encounter
frequency,
Bending Moment VS.
I
1.0
in
unusual
by
unexplained.
Hog
39
valid
regular
linear.
-
Fig.
is
in
response
points
Model
with
same
with
Along
length.
Station
+
from
appears
hlh
seas
question
Model
Sag
an
MARINER
and
the
under
1800
at
tests
wave-bending-moment
regular-wave
Moment
the
along
and
predict
hogging,
derived
technique
from
regular
moment
data
following
moment
stations
frequencies
responses
38).
that
in
wave
the
calculated
a~reement
the
from
of Bending
shown
the
better
do
these
than
obtained
been
where
show
at
superposition
are
have
region
than
Fig.
and
hogging
at
Theoretical
was
speed
of
peaks
it
39
that
finding,
36,
calculated
Variation
head
the
tests
were
non-linear
this
is
.
showed
Fig.
in
It
larger
functions
test
question,
1.25.
icantly
hull,
response
in
results
and
signi
da &
MARINER
motion
case
plotted
latter
the
the
ship
1.00,
are
irregular-wave
height.
the
derived
in
if
moderate
for
these
of
using
seas
0.75,
=
responses
analysis
Ochi,ealso
waves
k/L
at
regular
I
1.2
radlsec
Wave Encounter FTequency.
sagging
have
and
markedly
-32-
In
the
is
no
in
sagging
test
results
evidence
or
‘icargo
for
such
of
amidshipll
a double-peak
weight
trend
in
speed
6-26), there
(Figs.
distribution
any
or
heading
condition,
either
hogging.
SUMMARY
(1)
An
extreme
MARINER
condition
cargo
and
following
(a)
Reach
to
(b)
peak
(c)
OF
Are
in
the
are
regular
denoted
within
dynamic
stations
waves
to
“cargo
practical
wave
10 and
larger
in
moment,
total
bending
of
wave
amidship,”
operating
moments
for
limits
which
height/wave
the
in
head
--
length
ratios
up
12+.
wave
in
reasonable
sag
height
than
result
moment
Tests
of the
MARINER
hull
loading
in high
irregular
which
in
proportional
sagging
than
speeds
up
to
a wave-height/wave-length
0.11.
generally
water
(2)
values
between
distribution,
at
results
generally
ratio
weight
running
seas,
0.11
Are
of
ship
in
in
for
a
a more
with
head
when
sagging
weight
normal
added
to
moment
with
similar
a
sizable
still-
significantly
larger
distribution.
loadinci
and the
a normal
yield
wave-bend~ng-moment
both
seas
agreement
and,
hog
total
responsa
“carcio
amidship”
res~onse
results
curv’es
from
regular-wave
tests.
CONCLUSIONS
(1)
The
pract
and
full-scale
ce
of
concentrating
on
measuremen’cs
midship
appears
to
bending
be
moments
justified
both
for
in
ships
design
of
the
studies
MARINER
type.
(2)
The
good
agreement
in
confidence
technique
o
between
the
use
predict
of
the
irregular-wave
regular-wave
the
vertical
and
response
wave
regular-wave
operators
bending
moment
responses
and
of
a
inspires
spectral-analysis
ship
in
irregular
waves.
RECOMMENDATION
This
MARINER
six
broad
cargo
years
and
The
is
have
modei
believe
been
diminishing
results
of
has
documented
authors
steepness
yield
investigation
ship
in
that
the
a
bending
actively
series
to
of
five
trends
bending
stress
acting
over
of
on
the
hull
a-period
technical
the
extent
should
now
Efforts
full-scale
moments
continued
significant
established,
returns.
against
wave
been
of
girder
of
reports.
wave
bending
that
further
be directed
measurements
moment
with
work in
toward
collected
this
checking
wave
area
would
model
test
under
SR-153.
ACKNOWLEDGEMENT
The
Mr.
T.
testing,
M.
authors
Buermann,
and
data
wish
to
for
analysis
thank
its
the
Ship
guidance
phases
of
Response
Advisory
and
encouragement
the
project,
a
app~oximately
Panel,
during
1964-1965.
headed
the
planning,
by
model
-33-
REFERENCES
(1)
LEWIS,
E. V. and
Ship
M“
(2)
DALZELL,
Extreme
Ship
(3)
J.
June
(5)
(6)
N.
by
Research
Proqram
Serial
SSC-124,
November
of
Models
of
Serial
SSC-156,
Model
in
of
of
Extreme
M4RINER
SSC-155,
of
Bendinq
Midship
the
Ship
and
Ship
Structural
1959.
Experienced
and
Three
in
Variants.
1964.
Bendinq
Midship
in
Moments
Type
January
a Tanker
February
Investigation
M.,
Lonq-Ranqe
Investigation
Committee,
Serial
MARINER
a
Moments
Experienced
Destroyer.
Ship
in
Structure
1964.
Bendinq
Moments
Ship
Waves.
Within
Structure
the
Half
Midship
Committee,
Serial
Lenqth
SSC-163,
1964.
COMSTOCK,
Architects
OCHI,
of
A
G.,
Committee,
F., An Investigation
J.
Reqular
Waves
by Models
ktANIAR,
a
An
Waves
Structure
DAEELL,
Extreme
of
F.,
Reqular
Committee,
(4)
Gerard,
Structure
K.
Green
J. P.
(cd.),
and Marine
M.,
llExtreme
Water,”
Trans
—.
Principles
Engineers
Behavior
SNAME,
of Naval
Architecture.
(sNAME),
1967;
Chap.
of
Vol.
a
ship in Rough
72,
1964,
p.
IX
by
Society
E. V.
SeaS ‘- Slammin9
of Nava
Lewis,
p
and
‘h
660.
pping
143.
.
UNCLASSIFIED
Secl[ritv
Classiflcalton
DOCUMENT
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Davidson
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T,TLE
BENDING
MOMENT DISTRIBUTION
IN A MARINER
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AND
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DESCRIPTIVE
IRREGULAR
NOTES
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CARGO SHIP
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IN
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Final
AU
(First
THOR(S1
Naresh
M.
Edward
REPORT
name,
middle
‘asf
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Numata
7a.
DATE
November
1968
.. CONTRACTORGPAMTMO
b.
initial,
Maniar
PROJECT
NO.
TOTAL
NO.
OF
7!>.
PAGES
No.
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SR-i65
..
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OTHER
REPORT
th,.
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D, ST
R, BUTl
ON
5uPPLEME.N1&wY
of
this
document
is
nwnbcrs
that
rnuy
he .s.
iAned
unlimited
t40TE5
tb~;lllee
Systems
Command
of the Navy
D. C. 20360
‘2’Yl?Y~Y?~ti&YITI~Y
Naval Ship
Department
Washington,
3.
other
STATEMENT
Distribution
1.
(AtIy
Ssc-lgo
d,
O
NO(5)
ABSTRACT
An
experimental
investigation
was
wave-bending-moment
distribution
vertical
relationship
cargo
bending
moment
and
extreme
to
the
wave
determine
midship
(1)
the
half-length
steepness,
for
lengthwise
and (2)
the
a MARINER-type
ship.
A
beam.
between
undertaken
within
l/96-scale
The
model
beam was
was
cut
to
strain-gaged
form
to
six
measure
segments,
bending
which
moments
were
at
joined
the
hull
by
a flexure
cuts
5, 7+, 10, 12~,and
15.
stations
The model was tested
with
normal
weight
distribution
and with
an extreme
The range
of regular-wave
amidship”
loading
in both
head and following
seas.
ness
(height/length)
was 0.05
to 0.11;
‘the irregular
waves
had an equivalent
size
significant
height
of 39 feet.
at
“cargo
steepfull-
Within
practical
operational
limits
of speed
for
the MARINER-type
ship,
the
maximum wave bending
moments
in high
regular
waves were
found
to occur
in the
region
from amidships
to 0.125L
aft
of amidships.
Thus the practice
of concentrating
on
midship
bending
moments
both
in design
studies
and full-scale
measurements
appears
to be justified
for
ships
of the MARINER type.
Hogging
and sagging
moments
at any
section
were
found
to be generally
to wave-length
ratio
of 0.11,
the
ing-moment
and wave data
from
the
proportional
to wave height,
up to a wave-height
The bendsteepest
wave that
could
be generated.
tests
in irregular
waves were
processed
by spectral
analysis
to obtain
equivalent
regular-wave
responses.
These
were
shown ‘co be,
generally,
in good enough
agreement
with
the bending-moment
responses
obtained
directly
in
regular-wave
response
operators
and
regular
waves
to inspire
confidence
in the
use of
spectral-analysis
-irreqular
waves.
DD,F:5:,,1473
s/N0101-807-6811
technique
(PAGE
1)
to
predict
the
vertical
wave
bending
moment
of
a ship
in
Security
Class
iflration
4
~EY
Lltd
ROLE
Cargo
K
4
LI
c
WORDS
Wr
ROLE
WT
ROLE
*T
Ship
Ship
Hulls
Ship
Bending
Model
Tests
Water
Waves
Moment
m
UNCL/SSIFIED
S/N
0101
.807.
f,071
Secutity
Classification
A-31d09
NATIONAL ACADEMY OF SCIENCES-NATIONALRESEARCH COUNCIL
DIVISION OF ENGINEERING
This pro.jecti
nas been conducted under *he adviso~y guidane~ of the SW
Research Cf”m{tt@ of the NationaZ Academy of Sciences NationaZ Res@areh
C0Unei2. Yhe Committee asstinessuch cognizance of p~o~-eetsin mazkria2s,
design <nd fabz-kution as relatiingto improved ship stme-bmws, when such
activities are acceptied.bythe Aead~my and ass{gnd tiln-ough
its Maritime
recommends
TrarsporbationRese~rch Board. In addition, this e.ommititiee
research objectives and p~ojeets; p~ouides liaison and t~ekn<cal guidance to
such studies; ~evievs p~ojeek repo~ts; and stimulates productive avenues of
researeh.
SHIP
Chaiman:
RESEARCH
COMMITTEE
M. L. Sellers,
Naval
(I,
II,
III)
Architect
Newport News Shipbuilding and Drydock Co.
Vice Gka-bman:
J. M. Frankland (I, II, III)
(Retired) Mechanics Division
National Bureau of Standards
Membem
William
H.
Chief,
Buckley
Bell
(Retired)
Bath
Joseph E. Herz
Chief
Fletallurgist
(I,
II)
Design
Engineer
Sun Shipbuilding and Drydock Co.
G. E. Kampschaefer, Jr. (111)
Manager, Application Ellgineerlng
(111)
ARMCO Steel
Scientist
S.
Structural
rlorks Corp.
Clausing
Senior
Company
Chemist
Iron
D. P.
John E. Goldberg, (I, II)
School of Civil Engineering
PurdueUniversity
II)
(III)
Chief
and
I,
Criteria
Aerosystems
B. B. Burbank
U.
(
Structural
Steel
Corporation
Corporation
Noton (II, III)
Department of Aeronautics
and Astronautics
Stanford University
BryanR.
D. P, Courtsal
(II, 111)
Principal Hull Design Engineer
Dravo corporation
Stanley T. Rolfe (III)
Section Supervisor
U. S. Steel Applied Research Center
A. E. COX (I, 11)
LHA Project Director
Newport News Shipbuilding
and Drydock Co.
Merville Willis (I)
Assistant Naval Architect
Sun Shipbuilding and Dry Dock Co.
F. V. Daly (111)
Manager of Welding
Newport
and
News
Drydock
Shipbuilding
Co.
and
R.
i!.
Yagle
Department.
John
Senior
F.
Dalzell
Research
Hydronautics
(1)
Scientist
(II)
of
and
Marine
University
of
Naval
Architecture
Engineering
Michigan
Incorporated
(1)
- Advisorg Group I, Ship StPain Measurement & Anal>sis
(II) - Advisoyg Group 11, Ship Stmeku~aZ Design
(III) - Adviso~ GYoup 11~ Ship MetalZurgiealStudies
R. W. Rumke
Executive See~etaw
SHIP STRUCTURE COMMITTEE PUBLICATIONS
These documents are disbibuted by the Clearinghouse, Sp~ingfieZd,
Vu.
22151. These documents have been announced in the Technical
Abstract Bulletin (TAB) o.fthe Defense Documentation Center (DDC).
Cwneron Station, Alexandp~a, VA. - 22314, undep the -indicated AD numbexw.
SSC”178, A Survey of Some Recent British JJoPkon the Behavior of Warship
Stxwcrhwes by J. Clarkson. November 1966. AD 644738.
SSC-179, Residual Strains and Dis~laeements Within the Plastic Zone Ahead of
A Crack by J. Cammett, A’. R. Rosenfield, and G. T. Hahn. Novembe;
1966. AD 644815.
SSC-180, Experimental Determination of Plastic Constraint Ahead of a Sharp
Crack unde~ Plane-%~ain Conditions by G. T. Hahn and A. R.
AD 646034.
Rosenfield.
December
1966.
SSC-181, Results ,PromFull-Scale Measurements oj?Midship Bending St~esses on
Two ~y-Ca~go Ships- Report #2 by D. J. Fritch, F. C. Bailey, J. M.
Wheaton. March 1967. AD 650239.
SSC-182, Tuentg Y?ars of Researeh Unde~ the Ship Stmeture
A. R. Lykle, S, R. Heller,
December 1967. AD 663677.
R.
Jr.,
Niplsen,
SSC-183, Me_tallu~,jicalStm.m=b.me and the B?ittb
Morris C]hen. May 1968. AD 670574.
Corrrrrit-tee
by
and John Va.sta.
Behavior of Steel by
SSC-184, Exhaustim of Ductility in Compr~ssad 3ars tiithHoles by
S. Kabay~shi and C. Mylonas. June 1963. AD 67~4~7.
SSC-185, Effect o,FSu~faee Condition On The Exhnwtion Of Ductility .RyCoZd
or Hot S&aining by J. Dvorak and C. Mylonas, July 1968,
SSC-186, On the Effect of Ship Stiffness Upon tbe Structural Response of a
Cargo Shtp to an Inpukive Load by Manley St. Denis. September 135L
SSC-187, BieninialReport of Ship Structure Committee, June
SSC-188, Effect Gf Repeated Loads On The L&
Of fl]otckzd
And Welded Plates.
Kiefner.
October
1968.
Tmpe?ature Fracture Behavior
W. H. hlunse, J. P. Cannon and J. F.
1968.
SSC-189, T% Video Tape Recording of Ultrasonic Test In ormation by Robert A.
Youshaw, Charles H. Dyer and Edward L. ~rlscuo {0. October 1968.
SSC-190, Bending Moment Distribution In a Ma~iner Cargo Ship Model In
Regular and IrreguZa? Waves of Ext~eme Steepne~s. by Naresh M.
Maniar
and Edward
Numata.
November
1968.