Fig. 1 Bearing, jacking and intermediate web stiffeners
11/6/2016
Pertemuan XXI, XXV :
PENGAKU
(Stiffener)
Mata Kuliah : Struktur Baja
Kode MK
: TKS 4019
Pengampu : Achfas Zacoeb
Introduction
Stiffeners are secondary plates or sections which are attached to
beam webs or flanges to stiffen them against out of plane
deformations. Almost all main bridge beams will have stiffeners.
However, most will only have transverse web stiffeners, i.e. vertical
stiffeners attached to the web. Deep beams sometimes also have
longitudinal web stiffeners. Flange stiffeners may be used on large
span box girder bridges but are unlikely to be encountered elsewhere.
Fig. 1 shows an example of bearing, jacking and intermediate web
stiffeners
1
11/6/2016
Introduction (cont’d)
Fig. 1 Bearing, jacking and intermediate web stiffeners
Types of Stiffener
There are two principal types of stiffener as shown in Fig. 2:
Longitudinal web stiffeners, which are aligned in the span
direction
Transverse stiffeners, which are aligned normal to the span
direction of the beam.
Transverse web stiffeners are usually provided at bearing positions
and these are known as bearing stiffeners. For future maintenance it
is good practice to provide bearing stiffeners at jacking points (for
when girders have to be raised to free bearings for replacement).
Other transverse stiffeners are called intermediate transverse web
stiffeners.
2
11/6/2016
Types of Stiffener (cont’d)
a. Stiffeners on I-section girders
b. Stiffeners on box girders
Fig. 2 Types of stiffener
Stiffener Sections
A variety of sections have been historically used as stiffeners,
however the simple flat stiffener is the type almost always used in
modern designs. Stiffeners can be attached on one side of the plate
(single sided), or on both sides (double sided). Usually bearing
stiffeners are double sided, while intermediate web stiffeners are
single sided. Stiffeners can also be doubled up, or even trebled, to
form multi-leg stiffeners. A typically of stiffener sections is shown in
Fig. 3.
3
11/6/2016
Stiffener Sections (cont’d)
Fig. 3. A typically of stiffener sections
Functions
Stiffeners have one or both of the following functions:
Controlling local buckling, as shown in Fig. 4 and Fig. 5.
Connecting bracing or transverse beams, as shown in Fig. 6.
4
11/6/2016
Functions (cont’d)
Controlling local buckling
Local buckling occurs when a cross section is slender enough for
buckling to occur within the cross section, due either to
compression or shear.
The webs of bridge beams are usually vulnerable to local buckling,
but flanges are usually much thicker and inherently more resistant
to buckling.
Local buckling can occur due to transverse compression load e.g. a
web subjected to a bearing reaction, longitudinal compression load
e.g. from bending, or from shear.
In all cases the addition of a relatively small stiffener to a slender
plate can increase the resistance to local buckling substantially.
Functions (cont’d)
Fig. 4 Reasons for transverse stiffeners
5
11/6/2016
Functions (cont’d)
Fig. 5 Reasons for longitudinal stiffeners
Functions (cont’d)
Connecting bracing or transverse beams
The easiest way to brace steel beams together is by fixing the
bracing to transverse stiffeners.
Thus stiffener positions almost always coincide with bracing
positions.
In a ladder deck the webs of transverse beams can be connected
directly to the main beam stiffeners, so stiffener spacing matches
transverse beam spacing.
In a multi-girder bridge with cross bracing the bracing members
are usually connected to the main beam stiffeners, so that stiffener
spacing is the same as bracing spacing.
6
11/6/2016
Functions (cont’d)
Fig. 6 Stiffeners connecting bracing
Functions (cont’d)
Fig. 7 Failure due to the lack of stiffeners
7
11/6/2016
Design
There are two stages in the design of stiffeners:
1. The design needs to identify where stiffeners are needed for the
main beams to be adequate.
2. Then the stiffeners themselves need to be designed.
Basically, including plate girder principle design is shown in Fig. 8.
Design (cont’d)
Fig. 8 Principles of design
8
11/6/2016
Types of Stiffeners
Longitudinal
Stiffener
Transverse Intermediate
Stiffener
D
d o 1.5 D
Bearing
Stiffener
d o 1.5 D
Types of Stiffeners (cont’d)
Single Plate
Angle
Double Plate
Less than 6tw or more than 4tw
9
11/6/2016
Bearing Stiffeners
Most bridge beams will require bearing stiffeners, even if bearing
stiffeners are not required, they may still be provided if desired for
giving a benefit the shear resistance.
At end supports, if bearing stiffeners are to be provided, then a
decision has to be made as to whether to provide a “rigid end post”
or “non-rigid end post” as shown in Fig. 9.
Note that multi-leg stiffeners must be split into separate effective
cross sections and the loads divided between them.
Bearing Stiffeners (cont’d)
Fig. 9 End posts
10
11/6/2016
Bearing Stiffeners (cont’d)
Detailing:
At bearings, the stiffeners usually have to be quite substantial to
resist the high compressive forces and may possibly have to be
multi-leg stiffeners.
Usually a double sided stiffener is required to avoid a high
eccentricity of loading.
Bearing stiffeners are usually thicker than the web.
It is important to make sure the stiffener is “fitted” to the bottom
flange, which means the stiffener is ground to make good contact
with the flange (it means the stiffener's share of the axial force in
the effective stiffener section can be transmitted through direct
contact between the flange and stiffener.
Bearing Stiffeners (cont’d)
A simple way to determine the stiffener's share of the axial force is
to calculate the stress at its centroid, taking into account
eccentricity of axial force on the effective section, and then
multiply this stress by the stiffener area.
Welds are almost always continuous fillet welds all round both
sides of the stiffener.
A simple 6mm leg length weld may be adequate but often may
have to be 8mm or 10mm.
The weld has to be sized so as to be able to transmit the stiffener's
share of the bearing load into the web.
11
11/6/2016
Intermediate Stiffeners
It is usually necessary to provide intermediate stiffeners on main
beam webs for the practical purpose of connecting torsional
bracing between the beams.
The chosen bracing positions will determine the positions of at
least some of the stiffeners, for beams with no bracing , such as
transverse girders in a ladder deck bridge, or if plan bracing is
being used, there may be no practical necessity for intermediate
stiffeners at all.
The requirement for intermediate transverse web stiffeners is
determined by the verification of the shear resistance - this will
indicate where stiffeners are needed, and where stiffeners extra to
those for bracing are needed.
Intermediate Stiffeners (cont’d)
As a first step in design, it is suggested that initially is assumed
there are no intermediate stiffeners at all, it proves the beam to be
adequate in shear then the benefit of any intermediate stiffeners for
bracing attachment will be a bonus.
If the first procedure determines that intermediate stiffeners are
required, then the designer will need to choose the positions and
spacing of these stiffeners, and to decide whether they need to be
rigid.
Verification of the stiffener size is similar to that for bearing
stiffeners (loads on intermediate stiffeners are usually much less
than for bearing stiffeners but stiffeners may be still subject to
forces and moments due to interaction with transverse beams or
bracing.
12
11/6/2016
Intermediate Stiffeners (cont’d)
For example, in a ladder deck bridge, the shear in the transverse
beams will cause an axial force in the main beam stiffener (it may
also be horizontal loading to consider from the bracing which may
generate bending moments in the stiffener section).
Having determined the loading, verify the chosen stiffener size by
checking the adequacy of the effective stiffener section to act as a
column for combined axial force and bending moment (if any).
If there is no direct loading on the stiffener from any of the above,
it is only necessary to ensure the effective stiffener section satisfies
the stiffness criterion given in codes*.
*)
SNI 03-1729-2002: Tata Cara Perhitungan Struktur Baja untuk Bangunan Gedung
Intermediate Stiffeners (cont’d)
Detailing:
For intermediate transverse web stiffeners, the stiffener probably
does not need to be very big, typically a single sided 150x15mm
plate has adequate strength and stiffness.
Sometimes the stiffener size will have to be increased to
accommodate connections, it can be done by increasing the plate
size to 200G20mm or perhaps 250G5mm or alternatively it can be
locally increased to provide connection area.
Traditionally the stiffener width to thickness ratio has been limited
to no more than 10 to avoid local buckling.
13
11/6/2016
Intermediate Stiffeners (cont’d)
However, there are no restriction on this ratio, and more slender
stiffeners are permitted, although checks may need to be made that
they will not be at risk from local buckling.
It does not matter if the stiffener is thicker than the web, so
generally thicker stiffeners are recommended.
To give a clean appearance to the bridge, it is normal to design the
outer beams such that the intermediate transverse stiffeners are on
the inner face of the web and hence not visible on the elevation.
Unless there is a substantial axial force on the stiffener, a simple
weld detail such as a 6mm leg length continuous fillet weld all
round both sides of the stiffener should be sufficiently strong and
durable.
Longitudinal Stiffeners
As noted before, most bridges do not have longitudinal stiffeners.
To determine if longitudinal stiffeners are required on the web to
give the main beams sufficient shear strength, the procedure is as
for intermediate stiffeners, i.e. to verify the shear resistance of the
beam.
If they exist, longitudinal stiffeners can be continuous or
discontinuous as shown in Fig. 10, depending on whether they are
continuous through transverse stiffeners and diaphragms.
14
11/6/2016
Longitudinal Stiffeners (cont’d)
Discontinuous longitudinal stiffeners stop and start again either
side of the transverse stiffener so that they do not pick up global
longitudinal stresses from the web or flange to which they are
attached (they are there simply to resist buckling to the web or
flange).
Continuous longitudinal stiffeners, however, do pick up global
stresses and add to the cross section.
If longitudinal stiffeners are to be provided they are to be verified
by checking the adequacy of the effective stiffener section to act as
a column.
Longitudinal Stiffeners (cont’d)
Fig. 10 Longitudinal stiffeners
15
11/6/2016
Connections
Transverse web stiffeners are sometimes welded to the flange, and
sometimes stopped just short of either or both flanges.
The necessity for a connection to a flange depends on whether
forces need to be transferred to the flanges.
If there is a significant axial force to be transferred to the stiffener
from one of the flanges it will be necessary to weld the stiffener to
that flange.
Hence bearing stiffeners must be connected to the bottom flange if
part of the bearing reaction is to be transferred to the stiffener.
If there is bracing connected to the stiffener then it is likely that it
is necessary to weld the stiffener to the compression flange to
transfer the lateral shear force.
Connections (cont’d)
A connection to the top flange also prevents a fatigue problem in
the top flange to web weld as the deck tries to rotate over the beam
due to traffic loads.
The advantage of stopping the stiffener short of the flange is that it
avoids a potential water trap on the upper surface of the bottom
flange (it is particularly important to avoid on weathering steel
bridges).
A typically of connection to the flange as shown in Fig. 11 and
Fig. 12.
16
11/6/2016
Connections (cont’d)
Fig. 11 Stiffener to flange connections
Connections (cont’d)
Fig. 12 Stiffener widened for connections
17
11/6/2016
Connections (cont’d)
Where a stiffener is to be welded to a flange, normal construction
tolerances would result in a small gap between the stiffener and the
flange, unless the stiffener is fitted; all the forces will therefore be
transferred through the welds.
However, if a stiffener is fitted to the flange, the fabricator will
grind the stiffener end so as to make a good fit with the flange over
a substantial proportion of the stiffener area as shown in Fig. 13.
This exercise requires additional work (and cost) so stiffeners
should only be fitted when necessary, e.g. for bearing stiffeners and
for stiffeners at a change in flange direction.
Connections (cont’d)
Fig. 13 Types of connection
18
11/6/2016
Snipe and Cope Hole
At the corner of a transverse web stiffener where the stiffener plate
meets the web to flange weld, it will be necessary to shape the
stiffener to avoid the weld.
There are two options, either snipe the stiffener to suit the web to
flange weld and weld up all the interfaces, or provide a cope hole
as shown in Fig. 14.
Although the first option requires welding one weld on top of
another, this detail may be easier to fabricate than the second,
because it is difficult to satisfactorily complete continuous welds
around cope holes and apply paint to all of the surfaces.
Snipe and Cope Hole (cont’d)
Fig. 14 Details of snipe and cope hole
19
11/6/2016
Typically of Plate Girder
Fig. 15 Unstiffened and stiffened plate girders
Typically of Plate Girder (cont’d)
Fig. 15 Cont’d.
20
11/6/2016
Typically of Plate Girder (cont’d)
Fig. 16 Plate girder cross sections
Typically of Plate Girder (cont’d)
Fig. 17 Plate girder with haunches, tapers, and cranks
21
11/6/2016
Typically of Plate Girder (cont’d)
Fig. 18 Plate girder with hole for services
TERIMA KASIH
DAN
SEMOGA LANCAR STUDINYA!
22
Pertemuan XXI, XXV :
PENGAKU
(Stiffener)
Mata Kuliah : Struktur Baja
Kode MK
: TKS 4019
Pengampu : Achfas Zacoeb
Introduction
Stiffeners are secondary plates or sections which are attached to
beam webs or flanges to stiffen them against out of plane
deformations. Almost all main bridge beams will have stiffeners.
However, most will only have transverse web stiffeners, i.e. vertical
stiffeners attached to the web. Deep beams sometimes also have
longitudinal web stiffeners. Flange stiffeners may be used on large
span box girder bridges but are unlikely to be encountered elsewhere.
Fig. 1 shows an example of bearing, jacking and intermediate web
stiffeners
1
11/6/2016
Introduction (cont’d)
Fig. 1 Bearing, jacking and intermediate web stiffeners
Types of Stiffener
There are two principal types of stiffener as shown in Fig. 2:
Longitudinal web stiffeners, which are aligned in the span
direction
Transverse stiffeners, which are aligned normal to the span
direction of the beam.
Transverse web stiffeners are usually provided at bearing positions
and these are known as bearing stiffeners. For future maintenance it
is good practice to provide bearing stiffeners at jacking points (for
when girders have to be raised to free bearings for replacement).
Other transverse stiffeners are called intermediate transverse web
stiffeners.
2
11/6/2016
Types of Stiffener (cont’d)
a. Stiffeners on I-section girders
b. Stiffeners on box girders
Fig. 2 Types of stiffener
Stiffener Sections
A variety of sections have been historically used as stiffeners,
however the simple flat stiffener is the type almost always used in
modern designs. Stiffeners can be attached on one side of the plate
(single sided), or on both sides (double sided). Usually bearing
stiffeners are double sided, while intermediate web stiffeners are
single sided. Stiffeners can also be doubled up, or even trebled, to
form multi-leg stiffeners. A typically of stiffener sections is shown in
Fig. 3.
3
11/6/2016
Stiffener Sections (cont’d)
Fig. 3. A typically of stiffener sections
Functions
Stiffeners have one or both of the following functions:
Controlling local buckling, as shown in Fig. 4 and Fig. 5.
Connecting bracing or transverse beams, as shown in Fig. 6.
4
11/6/2016
Functions (cont’d)
Controlling local buckling
Local buckling occurs when a cross section is slender enough for
buckling to occur within the cross section, due either to
compression or shear.
The webs of bridge beams are usually vulnerable to local buckling,
but flanges are usually much thicker and inherently more resistant
to buckling.
Local buckling can occur due to transverse compression load e.g. a
web subjected to a bearing reaction, longitudinal compression load
e.g. from bending, or from shear.
In all cases the addition of a relatively small stiffener to a slender
plate can increase the resistance to local buckling substantially.
Functions (cont’d)
Fig. 4 Reasons for transverse stiffeners
5
11/6/2016
Functions (cont’d)
Fig. 5 Reasons for longitudinal stiffeners
Functions (cont’d)
Connecting bracing or transverse beams
The easiest way to brace steel beams together is by fixing the
bracing to transverse stiffeners.
Thus stiffener positions almost always coincide with bracing
positions.
In a ladder deck the webs of transverse beams can be connected
directly to the main beam stiffeners, so stiffener spacing matches
transverse beam spacing.
In a multi-girder bridge with cross bracing the bracing members
are usually connected to the main beam stiffeners, so that stiffener
spacing is the same as bracing spacing.
6
11/6/2016
Functions (cont’d)
Fig. 6 Stiffeners connecting bracing
Functions (cont’d)
Fig. 7 Failure due to the lack of stiffeners
7
11/6/2016
Design
There are two stages in the design of stiffeners:
1. The design needs to identify where stiffeners are needed for the
main beams to be adequate.
2. Then the stiffeners themselves need to be designed.
Basically, including plate girder principle design is shown in Fig. 8.
Design (cont’d)
Fig. 8 Principles of design
8
11/6/2016
Types of Stiffeners
Longitudinal
Stiffener
Transverse Intermediate
Stiffener
D
d o 1.5 D
Bearing
Stiffener
d o 1.5 D
Types of Stiffeners (cont’d)
Single Plate
Angle
Double Plate
Less than 6tw or more than 4tw
9
11/6/2016
Bearing Stiffeners
Most bridge beams will require bearing stiffeners, even if bearing
stiffeners are not required, they may still be provided if desired for
giving a benefit the shear resistance.
At end supports, if bearing stiffeners are to be provided, then a
decision has to be made as to whether to provide a “rigid end post”
or “non-rigid end post” as shown in Fig. 9.
Note that multi-leg stiffeners must be split into separate effective
cross sections and the loads divided between them.
Bearing Stiffeners (cont’d)
Fig. 9 End posts
10
11/6/2016
Bearing Stiffeners (cont’d)
Detailing:
At bearings, the stiffeners usually have to be quite substantial to
resist the high compressive forces and may possibly have to be
multi-leg stiffeners.
Usually a double sided stiffener is required to avoid a high
eccentricity of loading.
Bearing stiffeners are usually thicker than the web.
It is important to make sure the stiffener is “fitted” to the bottom
flange, which means the stiffener is ground to make good contact
with the flange (it means the stiffener's share of the axial force in
the effective stiffener section can be transmitted through direct
contact between the flange and stiffener.
Bearing Stiffeners (cont’d)
A simple way to determine the stiffener's share of the axial force is
to calculate the stress at its centroid, taking into account
eccentricity of axial force on the effective section, and then
multiply this stress by the stiffener area.
Welds are almost always continuous fillet welds all round both
sides of the stiffener.
A simple 6mm leg length weld may be adequate but often may
have to be 8mm or 10mm.
The weld has to be sized so as to be able to transmit the stiffener's
share of the bearing load into the web.
11
11/6/2016
Intermediate Stiffeners
It is usually necessary to provide intermediate stiffeners on main
beam webs for the practical purpose of connecting torsional
bracing between the beams.
The chosen bracing positions will determine the positions of at
least some of the stiffeners, for beams with no bracing , such as
transverse girders in a ladder deck bridge, or if plan bracing is
being used, there may be no practical necessity for intermediate
stiffeners at all.
The requirement for intermediate transverse web stiffeners is
determined by the verification of the shear resistance - this will
indicate where stiffeners are needed, and where stiffeners extra to
those for bracing are needed.
Intermediate Stiffeners (cont’d)
As a first step in design, it is suggested that initially is assumed
there are no intermediate stiffeners at all, it proves the beam to be
adequate in shear then the benefit of any intermediate stiffeners for
bracing attachment will be a bonus.
If the first procedure determines that intermediate stiffeners are
required, then the designer will need to choose the positions and
spacing of these stiffeners, and to decide whether they need to be
rigid.
Verification of the stiffener size is similar to that for bearing
stiffeners (loads on intermediate stiffeners are usually much less
than for bearing stiffeners but stiffeners may be still subject to
forces and moments due to interaction with transverse beams or
bracing.
12
11/6/2016
Intermediate Stiffeners (cont’d)
For example, in a ladder deck bridge, the shear in the transverse
beams will cause an axial force in the main beam stiffener (it may
also be horizontal loading to consider from the bracing which may
generate bending moments in the stiffener section).
Having determined the loading, verify the chosen stiffener size by
checking the adequacy of the effective stiffener section to act as a
column for combined axial force and bending moment (if any).
If there is no direct loading on the stiffener from any of the above,
it is only necessary to ensure the effective stiffener section satisfies
the stiffness criterion given in codes*.
*)
SNI 03-1729-2002: Tata Cara Perhitungan Struktur Baja untuk Bangunan Gedung
Intermediate Stiffeners (cont’d)
Detailing:
For intermediate transverse web stiffeners, the stiffener probably
does not need to be very big, typically a single sided 150x15mm
plate has adequate strength and stiffness.
Sometimes the stiffener size will have to be increased to
accommodate connections, it can be done by increasing the plate
size to 200G20mm or perhaps 250G5mm or alternatively it can be
locally increased to provide connection area.
Traditionally the stiffener width to thickness ratio has been limited
to no more than 10 to avoid local buckling.
13
11/6/2016
Intermediate Stiffeners (cont’d)
However, there are no restriction on this ratio, and more slender
stiffeners are permitted, although checks may need to be made that
they will not be at risk from local buckling.
It does not matter if the stiffener is thicker than the web, so
generally thicker stiffeners are recommended.
To give a clean appearance to the bridge, it is normal to design the
outer beams such that the intermediate transverse stiffeners are on
the inner face of the web and hence not visible on the elevation.
Unless there is a substantial axial force on the stiffener, a simple
weld detail such as a 6mm leg length continuous fillet weld all
round both sides of the stiffener should be sufficiently strong and
durable.
Longitudinal Stiffeners
As noted before, most bridges do not have longitudinal stiffeners.
To determine if longitudinal stiffeners are required on the web to
give the main beams sufficient shear strength, the procedure is as
for intermediate stiffeners, i.e. to verify the shear resistance of the
beam.
If they exist, longitudinal stiffeners can be continuous or
discontinuous as shown in Fig. 10, depending on whether they are
continuous through transverse stiffeners and diaphragms.
14
11/6/2016
Longitudinal Stiffeners (cont’d)
Discontinuous longitudinal stiffeners stop and start again either
side of the transverse stiffener so that they do not pick up global
longitudinal stresses from the web or flange to which they are
attached (they are there simply to resist buckling to the web or
flange).
Continuous longitudinal stiffeners, however, do pick up global
stresses and add to the cross section.
If longitudinal stiffeners are to be provided they are to be verified
by checking the adequacy of the effective stiffener section to act as
a column.
Longitudinal Stiffeners (cont’d)
Fig. 10 Longitudinal stiffeners
15
11/6/2016
Connections
Transverse web stiffeners are sometimes welded to the flange, and
sometimes stopped just short of either or both flanges.
The necessity for a connection to a flange depends on whether
forces need to be transferred to the flanges.
If there is a significant axial force to be transferred to the stiffener
from one of the flanges it will be necessary to weld the stiffener to
that flange.
Hence bearing stiffeners must be connected to the bottom flange if
part of the bearing reaction is to be transferred to the stiffener.
If there is bracing connected to the stiffener then it is likely that it
is necessary to weld the stiffener to the compression flange to
transfer the lateral shear force.
Connections (cont’d)
A connection to the top flange also prevents a fatigue problem in
the top flange to web weld as the deck tries to rotate over the beam
due to traffic loads.
The advantage of stopping the stiffener short of the flange is that it
avoids a potential water trap on the upper surface of the bottom
flange (it is particularly important to avoid on weathering steel
bridges).
A typically of connection to the flange as shown in Fig. 11 and
Fig. 12.
16
11/6/2016
Connections (cont’d)
Fig. 11 Stiffener to flange connections
Connections (cont’d)
Fig. 12 Stiffener widened for connections
17
11/6/2016
Connections (cont’d)
Where a stiffener is to be welded to a flange, normal construction
tolerances would result in a small gap between the stiffener and the
flange, unless the stiffener is fitted; all the forces will therefore be
transferred through the welds.
However, if a stiffener is fitted to the flange, the fabricator will
grind the stiffener end so as to make a good fit with the flange over
a substantial proportion of the stiffener area as shown in Fig. 13.
This exercise requires additional work (and cost) so stiffeners
should only be fitted when necessary, e.g. for bearing stiffeners and
for stiffeners at a change in flange direction.
Connections (cont’d)
Fig. 13 Types of connection
18
11/6/2016
Snipe and Cope Hole
At the corner of a transverse web stiffener where the stiffener plate
meets the web to flange weld, it will be necessary to shape the
stiffener to avoid the weld.
There are two options, either snipe the stiffener to suit the web to
flange weld and weld up all the interfaces, or provide a cope hole
as shown in Fig. 14.
Although the first option requires welding one weld on top of
another, this detail may be easier to fabricate than the second,
because it is difficult to satisfactorily complete continuous welds
around cope holes and apply paint to all of the surfaces.
Snipe and Cope Hole (cont’d)
Fig. 14 Details of snipe and cope hole
19
11/6/2016
Typically of Plate Girder
Fig. 15 Unstiffened and stiffened plate girders
Typically of Plate Girder (cont’d)
Fig. 15 Cont’d.
20
11/6/2016
Typically of Plate Girder (cont’d)
Fig. 16 Plate girder cross sections
Typically of Plate Girder (cont’d)
Fig. 17 Plate girder with haunches, tapers, and cranks
21
11/6/2016
Typically of Plate Girder (cont’d)
Fig. 18 Plate girder with hole for services
TERIMA KASIH
DAN
SEMOGA LANCAR STUDINYA!
22