Download Viaduct over Guadalhorce River and A

Viaduct over Guadalhorce River and A-92 Highway,
Málaga, Spain
Óscar Ramón Ramos Gutiérrez, PhD (c), Civil Eng., Head of Structures Division, APIA XXI – Louis Berger DCE, PCTCAN,
Santander, Cantabria, Spain; Assoc. Prof. of Steel Structures, Cantabria Univ., Spain; Marcos J. Pantaleón Prieto, PhD, Civil Eng.,
President, APIA XXI – Louis Berger DCE, PCTCAN, Santander, Cantabria, Spain; Full Prof. of Steel Structures, Cantabria Univ.,
Spain; Guillermo Ortega Carreras, Civil Eng.; Cristina Gaite González, Civil Eng.; José Manuel Martínez García, PhD (c),
Civil Eng., Structures Division, APIA XXI – Louis Berger DCE, PCTCAN, Santander, Cantabria, Spain; Rubén Magán Ocaña,
Civil Eng., Owner Technical Site Manager, INECO – ADIF, Antequera, Málaga, Spain. Contact: [email protected]
DOI: 10.2749/101686614X13830788505838
Keywords: post-tensioned box-girder;
steel tied arch; temporary fix point;
self-launching gantry; delta-shaped
pier.
Introduction
The need for the Guadalhorce Viaduct
project arises from the necessity to
give way to the Antequera–Granada
high-speed railway line. The bridge
is located in the Guadalhorce River
floodplain, and thereby requires such
a large length.
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The Guadalhorce Viaduct, built as part
of the high-speed line Antequera-Peña
de los Enamorados (south Spain), has
a length of 2525,50 m and consists of 49
spans of 51,25 m length each. It is one
of the longest bridges of its type in the
country and is situated in a mediumrisk seismic zone. The superstructure
consists of a continuous single-cell
post-tensioned box-girder of 3,40 m
depth. The main span, which crosses
the A-92 Highway, is 90 m long and is
reinforced by two steel tied arches. This
span, along with its backward and forward spans, was resolved with a steel–
concrete composite box-girder with a
constant depth of 3,40 m. A point of
fixity is materialized in a delta-shaped
post-tensioned concrete pier located in
an intermediate area of the bridge in
order to meet the friction, braking, and
seismic longitudinal forces induced by
the large length of the viaduct. Hence,
expansion joints are placed at both
abutments. Span-by-span erection is
being followed by means of two selflaunching formwork gantries working simultaneously, starting from each
abutment, and moving toward the
delta-shaped pier. Temporary fixed
points were required during the erection process and set at the piers placed
just before the gantry. The viaduct is
currently under construction.
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Abstract
Fig. 1: General view of the bridge
The main obstacles for the viaduct
to overcome were bridging the A-92
Highway that crosses underneath one
of its spans and the effects of the horizontal forces due to the large length.
To resolve these issues, a steel tied arch
and a post-tensioned concrete deltashaped pier were designed and incorporated into the structure (Fig. 1).
The bridge has a constant slope of 2,5%
in the vertical alignment, whereas the
plan view shows that the spans lie inside
a 3100-m radius with leftward circular
alignment, followed by two clothoid
alignments, and ending with a 2200-m
radius rightward circular alignment.
The deck houses a double-track railway platform containing 10,10-m
width of ballast, service sidewalks, and
several devices for the installation of
the railway at both sides, resulting in a
total deck width of 14 m, that is normal
in the high-speed Spanish railways.1
Two section types are present in the
bridge: a post-tensioned concrete box-
Structural Engineering International 1/2014
girder and a steel–concrete composite
box-girder, both with a constant depth
of 3,40 m. Both sections are continuous
throughout the entire viaduct (Fig. 2).
Typical Post-Tensioned Spans
The Guadalhorce Viaduct presents
some singularities due to both its
length (2525,50 m) and the need to
have a long-length span over the A-92
Highway. Consequently, two different
superstructure types may be found:
one used to span the highway and
another used to resolve the rest of the
viaduct.
The total number of spans is 49, each
51,25 m long, except for the one that
crosses the highway, which has a length
of 90 m.
The typical span consists of a continuous single-cell post-tensioned boxgirder of 3,40 m depth. This yields a
depth:length ratio of 1:15, which is
common for this type of bridges.2–4 The
Technical Report
105
(a)
PK 301+502,50
Rail expansion device
PK 304+028,00
Rail expansion device
2525,50
1269,00
E1 P1
39,00
1256,50
P29 P30
4×51,25
90,00
P25
24×51,25
P48E2
18×51,25
39,00
Fix point
15,16
15,39
A-92
Minimum clearance V = 14,18
Rio
Guadalhorce
(b)
P28
51,25 P29
39,25
P30
90,00
51,25
39,25
P31
A-92
Minimum clearance
V = 14,18
Steel-concrete composite box girder
Fig. 2: Elevation view of the Guadalhorce Viaduct: (a) complete viaduct, (b) steel–concrete composite superstructure spans (Units: m)
18,40
14,00
14,00
3,40
3,40
post-tensioning arrangement consists
of four families of four tendons per
family. Each tendon is compounded
of 27 strands of 15,2 mm diameter and
the tensile strength is equal to 1860 N/
mm2. The four families follow a vertical alignment that adapts to the flexural bending moment acting on the
superstructure.
5,50
5,50
Post-tensioned concrete box girder
Steel concrete composite box girder
1,50
Arch Span
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1,50
The deck type used for the span over
the highway, along with its backward
and forward spans, is a steel–concrete
composite box-girder design with a
constant depth of 3,40 m measured
at the axis of the bridge. The section
comprises a bottom flange of 5,50 m
width, sloped webs at both sides 7 m
apart at the top slab, and lateral overhang flanges of 3,50 m length. The top
reinforced concrete slab is 0,45 m deep
at the axis, decreasing to 0,375 m when
reaching the webs and 0,20 m at the
tip of the overhang flanges. Double
composite action has been designed at
the pier section in order to guarantee
the stability of the bottom flange and
decrease the steel plate thickness. This
kind of section has already been successfully used in other bridges.5
106 Technical Report
φ1,00
14,00
17,00 max.
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The longest span of the viaduct is
resolved with two steel tied arches. The
sag is 17 m long, which yields a sag:length
ratio of 1:5. The position of both arches
as well as their truss geometry respects
the skew angle formed by the viaduct
alignment and the highway, improving
the aesthetics. The transversal distance
between arch axes is 16 m and they comprise a 1,50 × 1,50 m2 section with slots at
the sides. The truss diagonals consist of
six tubular shapes per arch of 1 m diameter and 20 to 30 mm depth that creates
a triangular structure.
3,40
5,50
18,40
Steel-concrete composite box girder with steel tied-arches
Fig. 3: Typical sections: (a) concrete box-girder, (b) steel–concrete composite box-girder,
(c) steel–concrete composite box-girder with steel tied arches (Units: m)
The section is completed by two longitudinal steel ties of 1,95 m width.
Placed on each side of the deck, they
act as tension ties of the arch and are
connected to the arch truss. Anchorage
ribs are placed every 20 m at the junction between the triangular diagonals
and the longitudinal ties, connecting
them with the steel box-girder (Fig. 3).
Piers
The deck is supported by 48 reinforced
concrete piers. The maximum registered height is 27 m, although the via-
duct is placed in a flat valley and all the
piers are of similar height.
The typical pier consists of a constant elliptical section shaft, with 4,50
m transversal axis and 3 m longitudinal axis. A variable elliptical section
pier cap, which progressively widens
throughout the 4 m height in order
to house the deck-bearing devices, is
placed above the shaft.
The piers that support the arches
consist of two frames, located at each
side of the longest span, made of two
reinforced concrete shafts topped by a
Structural Engineering International 1/2014
lifetime, such as thermal expansion
and contraction, concrete shrinkage,
and creep and braking of the train
passing over the deck.
Typical pier
4,50
2,50
A
1,60
A
3,00
H
Once the fixity point is defined, the pier
design is created by the effect of the
longitudinal earthquake forces acting
on the deck. In the transversal direction, as most of the piers have similar
height and considering the length of the
structure, each pier absorbs noticeably
a proportional fraction of the force corresponding to its tributary length.
3,50
4,50
8 piles
φ1,80
A-A
12,00
4,00
Bearings and Rail Expansion
Devices: Monitoring
4,00
4,00
3,50
4,00
Arch pier
3,00
Deep foundations are needed for the
pier. Measuring 16,5 × 21,0 × 5,0 m,
each of them houses 18 drilled shafts
of 1,80 m diameter spaced 4,50 m
between axes (Fig. 5).
3,00
The bearing devices used on the viaduct consist of sliding bearings that
incorporate a PTFE (PolyTetraFluoro
Ethylene, Teflon) surface and have
suitable guides that restrict the movements. Two bearing devices are placed
on each abutment and pier. One of
them is a free bearing allowing movement in all directions, while the other
one is a guided bearing that allows
movement only in the longitudinal
direction to accommodate thermal
expansion/contraction of the deck.
8 Piles
φ1,80
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8 Piles
φ1,80
12,00
12,00
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12,00
6,30
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8 Piles
φ1,80
4,53
or
4,53
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3,50
23,00
3,50
Fig. 4: Pier geometry: (a) typical pier, (b) arch pier (Units: m)
the bridge, materialized in a deltashaped pier. It consists of two sloped
post-tensioned concrete shafts joint at
the basement by a horizontal beam.
The two shafts (2,85 m along the longitudinal axis and 5,50 m along the
transversal axis) converge at the deck
creating the fixity point of the viaduct
for the nonaccidental horizontal forces
induced in the bridge deck during its
Delta shaped pier
The large length of the viaduct has led
to the introduction of a fixity point,
located in an intermediate area of
5
2,8
5
28,146
The foundations of the piers supporting the span over the A-92 Highway
consist of 12 × 12 m2 spread footings,
with 3,50 m depth. Each of them houses
eight drilled shafts of 1,80 m diameter,
placed along three rows spaced 4,50 m
apart in both directions (Fig. 4).
2,8
5,50
5,00
Delta-Shaped Pier
The monitoring system records the
real gap between the abutment and
the superstructure, which depends on
5,00
horizontal post-tensioned bent cap that
confers transversal stiffness and provides support for the steel box-girder.
The four shafts are approximately 23
m high and form a rectangular section
whose dimension decreases from the
basement to the top. At the top, the
piers are only 4 m wide along the longitudinal axis and 3 m wide along the
transversal axis, whereas at the bottom
the longitudinal dimension is about
6,35 m and the transverse dimension
about 4,55 m.
Two rail expansion devices, with maximum opening of 1200 mm, are located
at both abutments. To adjust the
movement of the expansion devices, a
monitoring system that continuously
assesses structure integrity is installed
in the bridge. It tracks movements and
measures temperature of the concrete
wherever sensors are embedded.
2×18 Piles φ1,80
16,50
18 Piles φ1,80
16,50
21,00
Fig. 5: Delta-shaped pier geometry (Units: m)
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Technical Report
107
782,2
782,2
782
33,9
772,3
772,2
772
31,2
762,4
762,2
762
28,5
752,6
752,2
752
25,8
742,7
742,2
742
23,1
732,8
732,2
732
20,4
723,0
722,2
722
17,7
713,1
712,2
712
15,0
703,2
702,2
702
12,3
693,4
692,2
692
683,5
682,2
9,6
26/03/13 14:30
23/08/13 14:40
Time
Recorded gap (abutment-deck) (mm)
36,6
Recorded gap (abutment-deck) (mm)
Temperature (°C)
Viaduct over Gudalhorce River
structure 2. history record
(b)
26/03/13 14:30
X: time, Y: c14 «section 4. bottom slab. thermometer T17» (°C)
X: time, Y: c23 «abutment E2. recorded gap. láser L2» (mm)
Time
23/08/13 14:40
Expected gap (abutment-deck)
Viaduct over Gudalhorce River
structure 2. history record
(a)
682
X: time, Y: c23 «abutment E2. recorded gap. laser L2» (mm)
X: time, Y: mod02 «abutment E2. expected gap. (mm)
Fig. 6: (a) Recorded movements vs. temperature at abutment two. (b) Recorded movements vs. expected movements at abutment two
(Units: m)
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The real value of the thermal expansion coefficient of concrete α used in
the viaduct is 10 to 20% smaller than
the usual values of the codes in force.6,7
As is well known, the presence of limestone aggregate in the concrete may
lower the thermal coefficient value.6,8
or
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The theoretical time-dependent movement at the gap is known by means of a
step-by-step analysis model that counts
the real concrete ages according to the
erection procedure. The comparison of
the theoretical time-dependent movement and the time-dependent term of
the empirical formula (1) reveal that the
real time-dependent movement is about
90% of the theoretical movement.
g = gini − α·T·L + β·rhe(n, r, t)·L
(1)
where g, expected gap at a given time;
gini, initial gap; α·T·L, movement caused
by the thermal action; α, thermal
expansion coefficient of concrete; T,
temperature of the concrete at a given
time; L, distance from abutment to the
center of mass of the deck; β·rhe(n,
r, t) ·L, movement caused by the timedependent action; β, long-term strain
caused by shrinkage and creep of concrete; rhe(n, r, t), time evolution coefficient of shrinkage and creep (0 at the
beginning; 1 at the end); n, end time of
shrinkage and creep (in years); r, time
when shrinkage and creep are initially
considered; and t, age of concrete at
the time when shrinkage and creep are
initially considered (in years).
Empirical formula (1) is obtained
by linear correlation between the
recorded gap g and the recorded temperature T and the time evolution
coefficient of shrinkage and creep
rhe(n, r, t). With this formula, it is possible to determine the real values of
α and β coefficients for the concrete
used in the deck.
108 Technical Report
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thermal and time-dependent movements. Recorded gap–temperature
graph (Fig. 6a) shows that both variables are in the same phase. The gap can
be expressed in terms of the recorded
temperature and a time-dependent
function by means of the empirical formula (1). Recorded gap–expected gap
graph (Fig. 6b) shows good correlation
between both variables:
employed simultaneously in the viaduct, and so two different gantry suppliers were required. For the construction
of the first segment (spans located prior
to the steel arch), an upper self-launching formwork is used consisting of a
gantry placed above the deck, while
for the second segment, a lower selflaunching formwork is used and the
gantry is placed below the deck.
Temporary shoring towers will be
installed for the assembling of the
steel tied arch. The composite deck
segments, previously assembled at the
worksite, will be erected by cranes and
supported by the towers.
Temporary Longitudinal Fix
Points
Construction Procedure
The spans of the entire bridge, except
for the one over the A-92 Highway,
will be assembled by means of a selflaunching formwork gantry, as per the
sequence described below:
• Construction of substructure components (piers and abutments).
• Installation and assembly of the auxiliary equipment for the deck construction (self-launching formwork).
• Casting of concrete deck in subsequent phases; construction to begin
from the abutments and advance
toward the fixity point.
• Finishes: superstructure (ballast,
sleepers, rails, culverts, parapets, barriers, etc.).
To fulfill the construction deadline, two
self-launching formwork gantries are
Temporary fix points are needed during the construction stage in order to
absorb the longitudinal effects until
the connection between all the components and the delta-shaped pier takes
place.
The usual way of controlling these
effects consists of fixing the deck to the
abutment during the construction stage.
However, placing the temporary fix
point at the abutment in this long viaduct could lead to high relative movements during the concrete hardening
between the previous and the currently
cast span. It was then decided that the
temporary fix points would be placed
in the pier(s) of the previous cast spans.
To this purpose, the actions considered during each construction stage
Structural Engineering International 1/2014
to be acting on the piers, apart from
the self-weight of the components, are
the first-order longitudinal accidental eccentricity at the pier head, longitudinal force due to friction of the
sliding bearings, second-order effects,
superimposed deformations due to
thermal and shrinkage/creep effects,
and earthquake forces assuming a tenyear return period.
structures embedded on the deck and
the pier. The sizes of the steel structures
have been determined in accordance to
the maximum longitudinal force that
acts on the pier. The longitudinal lock
force acting on the deck is transmitted
by means of hydraulic jacks.
Structural Analysis
A unique three-dimensional (3D) beam
model for the entire viaduct was created, including a step-by-step analysis
of each construction stage. This model
allows an in-depth study of the timedependent effects, the thermal behavior between concrete and steel, and the
seismic response of the structure.
The special device designed to fix the
pier(s) consists of a group of steel
Seismic effects are considered in the
model because the viaduct is situated
When obtaining the natural period of
vibration in the longitudinal direction,
the axial flexibility of the superstructure (due to large length of the viaduct)
comes into play, as well as the bending
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The number of temporary fixed piers in
every phase depends on the superstructure length previously cast and, consequently, on the friction forces of the
sliding bearings. The number of fixed
piers increases from one to four, the biggest number being the worst scenario.
in a medium-risk seismic zone. The
seismic design was made according to
the Spanish seismic code for bridges
NCSP-07,9 which is quite similar to the
Eurocode 8.10 The basic ground acceleration of the site is 0,09g, whereas the
considered design ground acceleration
was 0,113g. As per Eurocode 8, ground
type C is found in the first 10 m and
type A in the following 20 m. The seismic effects were determined by means
of a modal response spectrum analysis,
using a linear elastic model of the structure and the design spectrum given by
the Spanish standard NCSP-07.
Fig. 7: First longitudinal vibration mode
(a)
S, Mises
Envelope (max abs)
(Avg: 75%)
+3,220e+08
+2,956e+08
+2,691e+08
+2,427e+08
+2,163e+08
+1,898e+08
+1,634e+08
+1,370e+08
+1,105e+08
+8,410e+07
+5,767e+07
+3,124e+07
+4,803e+06
Max: +3,160e+08
Elem: NUDO–1,17936
Node: 94
Min: +4,803e+06
Elem: NUDO–1,1105
Node: 350
(b)
N2
Q3
Min: +4,803e+006
N1
Y
X
Z
Max: +3,160e+008
Step: step-1
Increment 1: step time = 1,000
Primary var: S, Mises
Deformed var: U Deformation scale factor: +1,000e+00
Y
Z
N4
N3
Q4
X
Fig. 8: Shell FE-modeled connection nodes: (a) stress distribution diagrams, (b) adopted solution: double longitudinal exterior gussets
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Technical Report
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110 Technical Report
Conclusion
[8]
AASHTO
LRFD
Bridge
Design
Specifications, 6th ed. American Association of
State Highway and Transportation; 2012.
The Guadalhorce Viaduct has excelled
in establishing itself as one of the longest bridges of its type in the country. A
post-tensioned concrete box-girder section spans 2,5 km with a delta-shaped
pier as a unique fixity point. An accurate analysis of the thermal and timedependent coefficients of the concrete
could increase the length of this type
of bridge, since a smaller value of concrete strain would lead to a larger maximum length of viaduct for the same
rail expansion device opening.
References
[1] Reguero Martínez A. Tipologías de Viaductos
en L.A.V. Madrid-Barcelona-Frontera Francesa.
Revista de Obras Públicas 2004; 3445: 91–102.
[2] Pantaleón M, Ramos OR, Ortega G, Martínez
JM. Viaductos sobre río Deza y Anzo 2. V
Congreso de ACHE 2011; 1: 420.
[3] Manterola J, Astiz MA, Martínez A. Puentes
de Ferrocarril de Alta Velocidad. Revista de
Obras Públicas 1999; 3386: 43–77.
op
y
[4] Sobrino JA, Gómez MD. Aspectos
Significativos de Cálculo en el Proyecto de
Puentes de Ferrocarril. Revista de Obras
Públicas 2004; 3445: 7–18.
s
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[5] Pantaleón M, Ramos OR, Martínez JM,
Ortega G. Viaducto sobre rego das Lamas. V
Congreso de ACHE 2011; 1: 410.
or
Various finite element (FE) models
by shell elements were made, covering
the following variables: intersection
of tubes, gap between tubes, single
or double gusset, and longitudinal
or transversal gussets. According to
the analysis of the several solutions
the double longitudinal exterior gussets was the best solution, as shown
in Fig. 8. This solution allows a better
distribution of stress, offers better and
direct transmission of forces between
[7] Eurocode 2: Design of concrete structures.
European Committee for Standardization;
December 2004.
[9] Norma de Construcción Sismorresistente:
Puentes (NCSP-07). Gobierno de España,
Ministerio de Fomento; May 2007.
[10] Eurocode 8: Design of Structures for
Earthquake Resistance. European Committee
for Standardization; December 2003.
SEI Data Block
Owner:
ADIF, Ministerio de Fomento, Spain
Contractor:
ACCIONA, Spain
Torres Cámara, Spain
Site supervision:
GETINSA, Spain
GUIA, Spain
Structural design:
APIA XXI - Louis Berger DCE,
Santander, Spain
Concrete (m3):
Reinforcing steel (t):
Prestressing steel (t):
Structural steel (t):
Total cost (EUR million):
64530
14308
1280
1590
65
Service date: September 2015 (expected)
[6] Instrucción de Hormigón Estructural
(EHE-08). Gobierno de España, Ministerio de
Fomento; July 2008.
th
Several options were studied when
designing the connection nodes of the
truss diagonals with both the longitudinal ties and the steel arches. The
fatigue effects due to the railway traffic (highly important in high-speed line
bridges) and the stress concentrations
at the connection nodes were analyzed.
the tubes and the arch and tie girder,
and improves the fatigue behavior.
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stiffness of the delta-shaped pier foundation. Periods of 2,17 and 2,04 s for the
longitudinal vibration modes of the left
and right semi-viaduct, respectively, are
obtained, which are placed in the longperiod portion of the response spectrum. As these values are quite close,
the Square Root of the Sum of the
Squares (SRSS) combination method is
not considered accurate enough; hence
the Complete Quadratic Combination
(CQC) combination method was used
instead.10 The deformation of the deltashaped pier foundation was studied.
The maximum longitudinal seismic
force obtained in the delta-shaped pier
is 72 500 kN (Fig. 7).
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