Waiwera bridge - The Construction Of The Waiwera Viaduct - Creating Solutions Together
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Creating
Solutions
Together
Waiwera bridge
The Construction Of The Waiwera Viaduct
AUSTROADS 2009, AUCKLAND, NEW ZEALAND
Creating
Solutions
Together
Solving the Construction Of
Waiwera Bridge
Using Balanced Cantilever and
Matched Precast Segmental
E ti Vi
Erection Via O
Overhead
h dG Gantry
t
By David Trayner
VSL Australia Pty Ltd
AUSTROADS 2009, AUCKLAND, NEW ZEALAND
Creating
Solutions
Waiwera Viaduct
Together
• Part of the ALPURT B2 NZ$330m 7km extension to the motorway north of
Auckland
A kl d
• Delivered to Transit New Zealand by the Northern Gateway Alliance (NGA)
• NGA comprises Leighton Contractors, Fulton Hogan, Tonkin & Taylor, URS
NZ,, Boffa Miskell & Transit NZ
• Major elements of the project include: twin 300m tunnels, several small
Super T
T’s
s & the twin precast segmental balanced cantilever 521m long
bridges over the Waiwera River.
• Construction of the Waiwera bridge superstructures were executed by a sub
alliance between NGA and VSL. The structures were built using match pre-
pre-
cast segments manufactured on site, erected as balanced cantilevers via an
overhead
h d placement
l t gantry.
t
AUSTROADS 2009, AUCKLAND, NEW ZEALAND
Creating
Solutions
Together
Waiwera Viaduct is
located here:
AUSTROADS 2009, AUCKLAND, NEW ZEALAND
Creating
Solutions
Together
Waiwera Viaduct Plan
AUSTROADS 2009, AUCKLAND, NEW ZEALAND
Creating
Solutions
Together
AUSTROADS 2009, AUCKLAND, NEW ZEALAND
Creating
Solutions
Form Of Bridge
Together
• Form of bridge selected for:
• Optimum cost solution
• Constraints
• Cost
• Geographical
G hi l (steep
( t ravines,
i river
i flats)
fl t )
• Foundations (suited larger spans, high piers)
• Road alignment (steeper grades
grades, entry exit levels
determined by connections to other parts)
• Weather constraints (propensity for rain, high
wind, river valley / floods)
• Environmental sensitivity (native scrub, aesthetics)
• Logistics,
L i ti limited
li it d by
b low
l level
l l bridge
b id att Weranui
W i Rd
AUSTROADS 2009, AUCKLAND, NEW ZEALAND
Creating
Solutions
Form Of Bridge
Together
• Considerations
• Material costs (efficiency - haunched / continuous)
• Labour availability & costs
• Resource availabilityy existing
g plant & personnel.
• Combination of standard segments plus variable
depth segments
• Quality
Q lit (precast)
( t)
• Safety (maximum rationalisation)
• Solution
¾ Balanced Cantilever, pre-
pre-cast segmental by over head
gantry
AUSTROADS 2009, AUCKLAND, NEW ZEALAND
Creating
Solutions
Form Of Bridge
Together
• Summary
• 356 match pre-
pre-cast segments (Approx 1.040Km)
• 16 spans (2 carriageways
i - 8 spans each)h)
• Highest point off existing ground level = 30.5m
9 500m3 of concrete
• 9,500m
• 1,300T of reinforcement
• 12,130m2
, of bridgeg deck
• 480T of PT (cantilever 173t + continuity 307t)
• Segments were “glued” and initial stressed with temp
PT Bars
B
• Min / Max seg wght 50T (midspan
(midspan),), 83T (pier)
• Min / Max span 64
64.4m
4m / 76m
76m, & 41
41.1m
1m (end span)
• Typ segment length 2.9m
• Variable depth
p 4.3m (pier)
(p ) to 2.4m midspanp
• 11.7m deck width & nominal 3% cross fall (varying)
AUSTROADS 2009, AUCKLAND, NEW ZEALAND
Creating
Solutions
Together
Free Cantilever Method
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
Tunnel
entrances at
northern
h end
d off
structure
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
Typical Sequence
• Typical Sequence
• Launch Truss so that FSL is on next pier (N)
• Place, orientate & nail pier segment (on brg)
• Relocate FLCB on to pier N,N launch truss into
segment placement position.
• Erect cantilever segments “balanced”
balanced
• Acid etch, Apply epoxy “glue” & apply closure
prestress with PT bars
• Install permanent PT & stress
• Erect Closure Pour Segment & construct closure
pour
• Install permanent continuity PT, stress & grout
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
Gantry Operation
• Gantry
• Two parallel truss frames to support two overhead
gantry winches
• Truss was from a project
j from HK. Modified from
Span by Span simply supported with 46m long spans
to become a BC OH Gantry
• Overall
O ll length
l th off 140m
140 maded up off 15 maini elements
l t
in each truss
• Maximum element weight of 26T
• Total weight of truss and all its auxiliary components
is 730T
• Truss height of 4.0m, individual truss widths 1.6m.
• Underside of truss sits 7.0m above deck level
• End
E d spans constructed
t t d using
i span b by span method
th d
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together Gantryy Operation
p
• Gantry (Continued)
• The original truss req
req’dd lengthening
• an additional 40m was added
• Extended truss still not long g enough
g to launch
and place on the longest spans without an
intermediate step.
• New
N truss
t required
i d the
th front
f t supportt to
t be
b placed
l d
10m in front of the pier and the rear support to be
placed near midspan
midspan.. This increased the loads
on the deck and meant that full continuity
stressing & grouting of the span was required
before launching the truss
• It also put casting of the diaphragm and segment
nailing
ili on the
th critical
iti l path
th
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together Gantryy Operation
p
• Gantry (Continued)
• The linked criticality of the gantry operation to pier
segment erection was solved by erecting the pier
segments in advance with a 400t crawler crane
crane.
• Other challenges:
• Precast accuracies –
• Duct alignment – strand pushing, ducts
leaking
• Insert locations
• Wet weather – segmental gluing,
gluing water damage
to controls
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions Pakse Gantry
Together
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
Deep Bay Link Gantry
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
End Span – Span by SPan
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
Pier Segment Placing
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
Pier Segment
Placement
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
Pier Segment Erection By Crane
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
Pier Segment Erection By Crane
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
Segment Casting
• Precasting
• Two
T moulds
ld – “A” d
designated
i t d standard
t d d depth
d th
(2.95 to 2.4m) + “C” variable depth mould (4.3 to
2 95m) – also used to cast the smaller segments
2.95m)
• Typ
yp cycle
y 1 seg
gpper day
y for stnd depth
p 1 to 2
days for more complex variable depth segments
• Complex
C l segments t had
h d castt in
i situ
it sections
ti –
diaphragm / deviators. (Gantry limitations).
• Each mould had rebar jigs (top & btm separate)
• Rebar cages moved by OH Cranes / Forklifts
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
Segment Transporter & Straddle Carrier
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
Segment Casting
• Pre
Pre--casting (continued)
• Casting yard purpose built factory built on the alignment
• Segments
g moved using
g the transfer carts & straddle
carrier.
• Segment
S t storage
t on th
the alignment
li t
• 4% grade in storage area problematic for gantry cranes
solved by using Straddle Carrier & segment transporter.
• Segment delivered to gantry using Segment Transporter
Transporter.
• Straddle Carrier ran on a prepared road and was also
used to assemble truss
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
Segment Storage &
Casting Yard on Alignment
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
Casting Yard
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Together
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Segment Casting
Together
• Pre-casting (Continued)
• Challenges
• Labour skills, motivation, accuracy, supervision
• Concrete 60 MPa – challengingg g spec for long
g term
creep and shrink properties.
• High cement content Proved relatively “sticky” –
diffi lti in
difficulties i vibration,
ib ti req’d
’d high
hi h slumps
l
resulted in problems in concrete “slumping” out
of web forms.
forms
• Moved to high slump with accelerators but
“unforgiving” led to removal of accelerators and
a final mix with high cement content with target
slump of 140mm
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Programme
Together
• Project awarded on 9th May 2004, TCE completed Dec 2005
• Site handed over Jan 2006 (7 months late)
• Pre
Pre--casting
• 1st segment cast Jun 2006. Last cast 19th Dec 2007, target
schedule Sept 2007, best average 32 / mnth
• Gantry Operations
• Truss commissioned Jan 2007
• 1st Segment placed Jan 2007. Last placed April 2008, target
schedule Oct 2007
AUSTROADS 2009, AUCKLAND, NEW ZEALANDALPURT Baseline vs Actual
Creating
Solutions
Together
Abutment A2
350
Pier B2
Abutment A1
300 Pier C2
Pier B1 Launch Back to
250 Pier D
Pier C1
Cumulative
Baseline Casting
200 Pier D
As Cast
Baseline Erection
C
150 As Erected
Pier E
100
Pier F
Pier G
50
Abutment J1&2
Pier H
0
6/2006
7/2006
8/2006
9/2006
0/2006
1/2006
2/2006
1/2007
2/2007
3/2007
4/2007
5/2007
6/2007
7/2007
8/2007
9/2007
0/2007
1/2007
2/2007
1/2008
2/2008
3/2008
4/2008
5/2008
12/06
12/07
11/08
10/09
10/10
9/11
9/12
8/01
7/02
9/03
8/04
8/05
7/06
7/07
6/08
5/09
5/10
4/11
4/12
3/01
2/02
3/03
2/04
2/05
Week Ending
AUSTROADS 2009, AUCKLAND, NEW ZEALANDCreating
Solutions
Acknowledgments
Together
We would like to acknowledge and thank the following
f th
for their
i assistance
i t in
i the
th project
j t andd this
thi presentation:
t ti
Transit New Zealand, Leighton Contractors, Fulton
Hogan Tonkin & Taylor,
Hogan, Taylor URS NZ,
NZ Boffa Miskell
The Waiwera Bridge is a graceful, efficient and cost
effective
ff ti structure
t t delivered
d li d in
i challenging
h ll i
circumstances.
The Alliance’s demonstration of its ability in overcoming
obstacles has been rewarded by y the award of the
Newmarket Viaduct in Auckland with an even more
challenging and innovative solution –
“W t h Thi
“Watch This Space”.
S ”
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