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Review article

Recent development of design and construction of medium and long

span high-speed railway bridges in China

Nan Hu a, Gong-Lian Dai b, Bin Yan b,, Ke Liu b

a Department of Civil and Environmental Engineering, Michigan State University, East Lansing, MI 48824, USAb School of Civil Engineering, Central South University, Changsha, Hunan 410075, China

a r t i c l e i n f o

Article history:

Received 18 September 2013

Revised 26 May 2014

Accepted 30 May 2014

Available online 20 June 2014

Keywords:

High-speed rail

Bridges

Design

Construction

Medium-span

Long-span

a b s t r a c t

Medium- and long-span bridges of the high-speed rail (HSR) projects play a significant role when crossing

certain obstacles, such as rivers, existing highways, etc. This paper provides a state-of-the-art review on

the design practice of these special spans in the HSR projects of China. Given standard spans are usually

smaller than 100 m, special spans canbe divided into two categories by the lengthof main span: medium

length (100200 m) and large length (200500 m). For medium length, three structural forms are dis-

cussed as feasible design options, including steel arch, rigid frame and hybrid arch-girder. In addition,

recently completed long-span bridges are reviewed to feature several innovative structural forms on

the HSR of China, including steel truss arches and cable-stayed bridges with truss girder. Finally, the

key technical features of long-span HSR bridges are summarized, and a discussion of the feasibility of

longer spans is also included.

2014 Elsevier Ltd. All rights reserved.

Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233

2. Deflection control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234

3. Medium length (100200m). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235

3.1. Tied steel arch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235

3.2. Rigid frame . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236

3.3. Arch-rigid frame hybrid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237

4. Long length (200500 m). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237

4.1. Steel truss arch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237

4.2. Cable-stayed bridge with truss girder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239

5. Discussion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239

6. Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240

Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240

1. Introduction

High-speed rail (HSR) offers a fast and robust travel option that

enhances the quality of life and supports economic growth. Japan

was the first country to build a passenger dedicated line for high

speed travel, also known as Shinkansen. The first Shinkansen

opened Tokyo-Osaka segment for the Tokyo Olympics in 1964.

HSR in Europe first developed in several countries and now

expanded into a regional service network. Over the past few dec-

ades, a total of 13 countries have developed the HSR network,

mainly in Europe and East Asia. International examples from those

countries have proved that high speed trains are capable of reach-

ing speeds over 250 km/h on high speed passenger dedicated line

which significantly reduce the travel hours. Detailed historical

http://dx.doi.org/10.1016/j.engstruct.2014.05.052

0141-0296/2014 Elsevier Ltd. All rights reserved.

Corresponding author. Tel.: +86 13787799105.

E-mail addresses:[email protected](G.-L. Dai), [email protected](B. Yan),

[email protected] (K. Liu).

Engineering Structures 74 (2014) 233241

Contents lists available at ScienceDirect

Engineering Structures

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reviews of the development of HSR in those countries can be found

in papers by Taniguchi[1], Bouley[2], the European Commission

[3], Gourvish[4], Zuber[5], and Harrison et al. [6].

HSR in China is composed of upgraded existing lines with an

average design speed of 250 km/h and new lines with an average

design speed of 350 km/h, including 9356 km of new built lines

and 3209 km of upgraded lines. By 2020, the total length in China

will reach more than 20,000 km with a complete grid network that

will connect all provincial capital cities as well as large cities with

population more than five million. For a typical HSR line in China,

most spans are composed of standardized simply-supported beam

(with span of 24 m, 32 m and 40 m) when spanning lower than

40 m and a few standardized continuous beam bridges (main span

from 48 m to 100 m). For example, 95% bridges in the Beijing

Shanghai segment are standard span (90% simply-supported beam

along with 5% continuous beam) and only 5% are special spans.

Even though medium and long span bridges only cover a small por-

tion of a HSR line, it plays a key role in the completion of the entire

line, crossing over physical barrier such as existing highway, HSR

lines and rivers, etc.

The selection of a rational and cost-effective structural form is

the main assignment in bridge design. Structural forms for long-

span railway bridges have evolved during the past two centuries,

primarily featuring with longer span and more diverse forms. On

the heel of the birth of the steam railways, iron truss bridges

were widely constructed to support these earliest railway trains.

In the late 19th century, three milestone railway bridges were

successively built to support the larger live load of trains, includ-

ing the Eads Bridge (1874, 158 m), the Brooklyn Bridge (1883,

486.3 m), and the Firth of Forth Rail Bridge (1889, 521 m). These

bridges represented the advanced building techniques used on an

arch bridge, a suspension bridge and a cantilever truss. The devel-

opment of those well-recognized spans relied on the use of steel

rather than iron which reduced the dead load weight. As railroads

expanded throughout the world in the early 20th century, engi-

neers raced to design bridges that were stronger and longer,

without adding too much weight. A number of longer spans weredeveloped, such as the Hell Gate Bridge in New York (1916), and

the Sydney Harbor Bridge (1932). In the 1970s, Japan began the

construction of the Honshu-Shikoku Bridge Project, connecting

Honshu and Shikoku islands. The link between Okayama and

Kagawa is the only one with railroad connections. A total of six

long-span bridges were built to support both the highway and

the railway, including a continuous truss bridge, two cable stayed

bridges, and three suspension bridges. Currently, China is the

leading country in the large number of regular rail upgrades

and new HSR constructions.

The development of railway bridges in China began with the

completion of the Qiantang River Bridge in 1937. Two milestone

steel truss bridges were built subsequently across the Yangtze

River in Wuhan (1957) and in Nanjing (1968). Since then, the steeltruss bridge was used as the main structural form for the railway

bridges in China until the first cable-stayed bridge with a main

span of 312 m was completed in Wuhu over the Yangtze River in

2000. Then, a series of cable-stayed bridges were planned and con-

structed [7]. Similar to the design of standard spans for HSR, the

design of special spans also require a strict service limit due to

the need for smoothness of the track and the stability of the high

speed train. For a certain span range and site condition, several

options of structural form are available [8,9]. Special spans in

HSR of China can be divided into two categories by the length of

the main span: medium length (100200 m) and large length

(200500 m). Several cable-stayed bridges with a longer main span

more than 500 m are also included in the long spans. No

suspension bridges are currently used in the HSR of China. The sus-pension bridge is too flexible to maintain low deflection on main

girder and tracks such that it is not easy to meet the service limits

of HSR. Further studies on the use of HSR suspension bridge in

China is still in progress.

The objective of this paper is to present an up-to-date review of

the emerging design and construction techniques on medium and

long spans on the HSR of China, including the key design

philosophies, the main structural dimensions and the construction

methods. For medium length bridges, three forms are discussed,

including steel arch, rigid frame and hybrid arch-girder. For large

length bridges, the discussion focuses on steel truss arches and

truss cable-stayed bridges. This paper summarizes the structural

options for special spans for future HSR constructions.

2. Deflection control

HSR requires high deflection limits to ensure track smoothness.

No matter what structural forms selected for the special spans, the

control of the deflection on the main girder is still a key design

issue because the average design speed of trains on those spans

is more than 250 km/h[10]. The threshold limits on bridges with

a ballastless track bed are higher than bridges with ballast track

bed, because it is difficult to adjust the smoothness on the ballast-

less deck. Thus, all the long-span HSR bridges in China used ballast

track. However, no detailed requirements are applied to long-span

bridges, since the design and analysis of those bridges are usually

carried out case by case, which at least should satisfy those mini-

mum limits of small span HSR bridges. Four key aspects on the

deflection control on small span are as follows: (1) Vertical deflec-

tion of the beam, smaller than 2.0 mm; (2) the rotation at the beam

end, smaller than 0.4%; (3) long-term deflections (for example,

creep effects), smaller than L/1000 (L in m and result in mm); (4)

longitudinal deflection of the substructure. All those requirements

must be met in order to ensure the smoothness of the track and the

safety of the trains.

Track stability and smoothness of the HSR is highly dependent

on the control of the vertical and lateral deflection of the maingirder. Design specifications by the former Ministry of Railways

(MOR) of China have certain requirements on short-term and

long-term deflection on short length continuous beams [11]:

the vertical deflection must be smaller than 1.1 L/1000 (L is the

main span); lateral deflection must be smaller than L/4000; and

beam end rotation must be smaller than 0.2% in a ballast track

bed and 0.1% in a ballastless track bed. However, no such

requirements in the design specifications have been proposed

for special spans, including the medium length continuous beam,

the arch bridge and the cable-stayed bridge. Deflection limits on

similar bridges from international examples were studied and

compared to develop a recommended range for the long-span

designs [12].

Due to higher serviceability limits compared to conventionalrailway bridge design, other technical issues associated with

dynamic response of HSR bridges have been studied by many pre-

vious studies, such as seismic performance [1317], trackstruc-

ture interaction[1820], creep effect[21,22], thermal effect [23],

etc. In the development of HSR bridge in China, those special issues

(such as thermal expansion, seismic design, wind effect and creep

effect) have been considered and additional analysis may be

required for multiple loading cases that may cause large deflection.

(1) A single span over 100 m long requires measures to control the

thermal expansion and contraction of the rail, because the contin-

uous welded tracks could become distorted in hot weather and

cause the derailment of a train. Clips and anchors were widely used

in the HSR on multiple span bridges[24]. Zhu[25] compared the

multiple combinations of expansion devices on a cable-stayedbridge. It were found that the optimal way to control the thermal

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effect on the track is through the use of the small clips in certain

spots along the main girder and large expansion devices at both

end of the girder. Yan [26] carried out a numerical analysis on a

single-tower 112 m long cable-stayed bridge and proved that

longitudinal movement and the stress level of the rail canbe signif-

icantly reduced through using expansion device at the joint seg-

ment of the tower and the girder. Performance-based

requirements on seismic hazards are mentioned on the HSR design

code of China, but those general requirements are only applied to

small span bridges (i.e. main span smaller than 48 m). (2) Seismic

design and analysis is required for long-span HSR bridges in China

yet varied case by case. For example, Yue[27]showed that most of

the long-span HSR bridges did install dampers along the

longitudinal direction to reduce the large dynamic response under

earthquake or emergency braking of the trains. (3) Similar to the

seismic design issue, the aerodynamic effect of long-span bridges

is also considered case by case, but the design process of most

long-span bridges in China have went through dynamic analysis

along with multi-scale wind tunnel tests. Li et al. [28]and Wang

et al. [29] found that the deflection of the main girder can be

affected by train speed and wind speed. Li [30]carried out a wind

tunnel test on a twin girder linked by a cross-beam to identify the

optimal pattern of depth-width ratio for a better aerodynamic

performance. (4) Excessive long-term deflection (creep effect)

may result in an uneven track surface, which could threaten the

operation of HSR trains. For the medium and large-span of HSR

bridges, all the long span HSR bridges currently used ballast track,

which the creep effect was easier to adjust than ballastless track.

From structural design point of view, the creep effect is controlled

by increasing the depth of beam and lowering the difference of

stress between beam top and beam bottom under long-term

loading combination. In addition, the train speed has been

restricted to lower than 250 km/h to reduce the induced vibration.

It should be noted that the design philosophy of considering creep

effect in the Chinese design code is very conservative and

improvement on the requirement of the long-term effect is

undergoing.Overall, three most important limits for designing HSR bridges

in the future is to ensure the vertical stiffness, beam end rotation

and longitudinal stiffness of piers. It is note that no large structural

health monitoring system has been reported to record the deflec-

tion history on the HSR bridges in China, but there are undergoing

studies on the optimal arrangement of sensors, the use of different

monitoring system and the fast diagnose of damage, etc.

3. Medium length (100200 m)

Medium length spans are usually adopted to cross over the

existing highways or railroads. Most of the standard spans have a

main span smaller than 100 m and the maximum span is only

128 m. Even though the prestressed concrete continuous beam is

still one of the options, alternative forms can be chosen for HSR

special spans.Table 1lists a total of 19 medium length spans thathave been completed in the past five years. It can be seen that the

tied steel arch bridge and the rigid frame bridge are two commonly

used structural forms. The hybrid system of these two forms also

offered new solutions for the design of special spans. The detailed

description on each form will be discussed in this section using

design examples.

3.1. Tied steel arch

Commonly used steel arch bridges can be divided into tubular

arch and box arch by the cross-section of the arch rib.

The tubular arch, also known as the concrete filled steel tube

(CFST) arch, has been used in the Wuhan-Guangzhou segment of

the BeijingGuangzhou line [31]. Tian et al. [32]proved that thisarch type with inclined hangers has better dynamic characteristics

including greater vertical and lateral stiffness than other arch

types. It is noted that the 112 m long tubular arch with inclined

hangers was standardized as shown in Fig. 1a such that this design

can be used in similar conditions for spanning existing lines. The

rise to span ratio of the main arch is 1/5 with a rise of 22.4 m from

the top of deck [33]. The uniform-depth arch ribs have a twin

circular tube connected by cross links filled with low shrinkage

concrete. Each tube has a diameter of 1.28 m with a wall thickness

of 18 mm. Two main arch ribs are inclined inward about 9, which

has better dynamic characteristics including greater vertical and

larger lateral stiffness. The spacing of the hangers is 8 m. The arch

was designed without horizontal thrust due to the use of prestress-

ing tendons as tied bars in the main girder. The main girder is a sin-

gle box prestressed concrete structure with a depth of 2.5 m and a

width of 17.8 m. The estimated structural responses under the

dead load are a vertical deflection of 19.4 mm and a beamend rota-

tion of 0.0705%. Estimated material costs per unit length (one

meter) are 37.2 m3 of concrete, 8.9 tons of steel and 2.1 tons of

the prestressing tendons. Small clips on the main girder and large

expansion devices at both ends of the girder are used to meet the

smoothness requirements. The construction of this bridge started

Table 1

Recent completed medium length special span in the HSR of China.

Structural type Bridge name Main span (m) HSR segment Built

Tied steel arch East Lake 112 Wuhan-Guangzhou 2008

Hujiawan 112 Wuhan-Guangzhou 2008Liangjiawan 112 Wuhan-Guangzhou 2008

Tingsihe 140 Wuhan-Guangzhou 2008

Yandangshan 2 90 Ningbo-Wenzhou 2009

Mulanxi 128 Fuzhou-Xiamen 2009

Xinkaihe 138 Harbin-Dalian 2012

Rigid frame Tianluo 160 Wenzhou-Fuzhou 2008

Baimahe 3 145 Wenzhou-Fuzhou 2008

Liuxihe 168 Wuhan-Guangzhou 2009

Zinihe 2 168 Guangzhou-Shenzhen 2010

Hybrid steel arch with concrete girder Kunyang 136 Wenzhou-Fuzhou 2007

Yichang Yangzte 2 275 Yichang-Wanzhou 2008

Shawan Channel 160 Guangzhou- Shenzhen 2009

Liugangyong 160 Guangzhou- Hong Kong 2010

Xiaolan Channel 220 Guangzhou-Zhuhai 2010

Zhenjiang Channel 180 Beijing-Shanghai 2010

Xianyang West 136 Xian-Baoji 2012

Songhuajiang Channel 3 156.8 Harbin-Qiqihar 2013

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with the fabrication of the arch ribs along with concrete cast as a

tied beam. Then, the ribs are vertically rotated to the positions at

the temporary hinges that are installed at four spring lines [34].

Additional analysis during the rotation of the ribs was carried

out to ensure the stress concentrations at the spring line meet

specification [35].

The Tingsihe Bridge built in 2008 is a classic example of tied box

arch bridge for supporting a double track HSR line, as shown in

Fig. 1b. This 140 m-long arch bridge has a rise-span ratio of 1/5.

The 2.0 m uniform width arch ribs have a thin-wall rectangular

cross-section with a depth varying from 3.0 m at the crown to

4.5 m at the spring line. The spacing between ribs is 16 m, con-

nected with five lateral bracings. Underneath each rib, a single

box steel girder with a depth of 3.5 m and an inner width of

1.94 m is adopted as a tie to the arch rib. The hangers are designed

as rigid components with equally spaced holes to improve the

aerodynamic characteristics. The construction of this bridge con-

sumed more than 3800 tons of steel. The cantilever method was

used to erect the arch rib by segments to avoid interruption of

the highway operation and reduce costs. The segments of the rib

are hoisted by heavy duty truck cranes through temporary blocked

half lanes on the highway without using falsework during the ribinstallation [36]. The estimated structural responses under dead

load include a vertical deflection of 48.7 mm and a beam end

rotation of 0.186%[24]. Due to the high rotation at the end of tied

girder, a short length beam is adopted as a transition element

between the arch and the neighboring 32 m simply supported

beam. Tied box arch bridges among the completed bridges, include

other forms[37], as shown inFig. 1c and d.

3.2. Rigid frame

Due to the rigid connection between the beam and pier, rigid

frame bridges can span a greater length and provide better vertical

stiffness when compared to continuous beams [38]. This form ispreferable at good site conditions; otherwise it may suffer from

uneven settlement of the substructure, which leads to the

reduction of track smoothness. Completed examples on the HSR

line include the Tianluo Bridge (88 + 160 + 88) m (Fig. 2a) and

the Liuxihe Bridge (84 + 168 + 84) m [39] (Fig. 2b). These two

bridges have a similar structural configuration. Thus, only the Tian-

luo Bridge was selected for the discussion of the structural design.

The Tianluo Bridge is planned to span a shallow strait with a

design wind speed reaching 56 m/s. This prestressed concrete

structure was selected to satisfy the required clearance of

120 24 m. The cross-section of the superstructure is a varied-

depth box with a top width of 13 m and bottom width of 8.2 m.

At the rigid connection to the pier, the box girder has a depth of

(a) Hujiawan Bridge (b) Tingsihe Bridge

(c) Yandangshan Bridge (d) Xinkaihe Bridge

Fig. 1. Steel arch bridges in the HSR of China.

(a) Tianluo Bridge

(b) Liuxihe Bridge

Fig. 2. Rigid frame bridges in the HSR of China.


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9.8 m, a top wall thickness of 55 cm, a bottom wall thickness of

100 cm and a web wall thickness of 150 cm. At the two support

columns, the bottom wall thickened to 200 cm. At the mid-span

and the end of side span, the box girder has a depth of 5.0 m, a

top wall thickness of 45 cm, a bottom wall thickness of 50 cm

and a web wall thickness of 100 cm. Three additional thin walls

are added in the lateral direction of the girder to main its stability,

including two 160 cm thick walls at the end of each side span and

one 80 cm thick wall at the mid-span. Two-way drainage is used on

the bridge deck with a slope of 2%. The prestressing tendons are

used in all three directions of the girder to ensure the main struc-

ture is in a complete compressive stress state. The pulling pres-

sures in prestressing jacks are usually between 1230 and

1300 MPa. Due to high corrosion potential at the bridge site, high

performance C60 Grade concrete was used. The consumption of

materials per meter for the beam is 26.1 m3 of concrete, 3.3 t of

steel and 1.5 t of prestressing tendons.

The supports of a rigid frame are commonly two thin wall legs.

In this case, two vertical legs with a spacing of 8 m are used with a

leg height to main span ratio of 0.2, which maintain an optimal

stress distribution on the legs and beams. The leg has a lateral

width of 10 m and a longitudinal width of 2.2 m. The use of two

legs improves the longitudinal stiffness of the beam and provides

a relatively flexible constraint for the mid-span as compared to sin-

gle leg. The two legs are supported by a cubic concrete pile cap

(14.5 m 19.7 m 5 m) and 12 drilled piles with a diameter of

2.5 m. C45 Grade concrete is used for the legs and C30 Grade

concrete is used for the pile cap.

Commonly, the cantilever method is adopted in the construc-

tion of a rigid frame. The erection of the girder starts from the sup-

ports and the closure is in the mid-span and the end of each side

span. The key issue for the cantilever method is that real-time

monitoring is required to measure the position of each segment

and maintain a theoretical line shape at the top of the girder

[38]. For the Tianluo Bridge, additional analysis was needed to

measure and control the dynamic response of the girder during

the construction phases. Gong [40] carried out the dynamicanalysis for this bridge and found that the actual response of the

structure was better than the estimate from an integrated model

of the train and the structure. It was also found that the stability

of a running train can be improved by increasing the depth of

the noise barrier.

3.3. Arch-rigid frame hybrid

As discussed previously, both the tied steel arch and the rigid

frame bridge offer certain advantages on the HSR line. The hybridsystem of these two forms is also an alternative choice when the

use of a steel arch or a rigid frame cannot satisfy the clearance

requirement. Examples in the HSR line of China include the

Kunyang Bridge in Fig. 3a and the Yichang Yangtze River Bridge

in Fig. 3b. The key structural features of this hybrid system are dis-

cussed below as related to the Kunyang Bridge.

The Kunyang Bridge supports a double-track joint passenger-

freight HSR line with a main span of (64 + 136 + 64) m. The

11.5 m wide main girder of the Kunyang Bridge has a double-box

cross section with a varied depth from 3.5 m in the mid-span to

7.0 m at the support. High performance C60 Grade concrete was

used to improve the durability of structural performance under

the environmental impact. These dimensions are smaller than a

solely rigid frame structure because the live load is partially sup-ported by the steel arch. The rise to span ratio of the main arch

is 1/5 with a 27.2 m rise from the top of deck. The uniform-depth

arch ribs have a twin circular tube filled with low shrinkage C50

Grade concrete. Each tube has a diameter of 2.8 m with wall thick-

ness of 16 mm. Two arch ribs are connected by nine lateral truss

bracings[41]. A total of 14 pair of hangers are used with a spacing

of 8 m. High stress concentration at the joint region between on

steel rib and concrete girder was reduced by using a special con-

nection[42]. The construction of such bridge per meter consumed

more than 23.6 m3 concrete and 8.8 tons of steel. The common

sequence of construction started from casting the girder segment

by the cantilever method followed by the erection of arch ribs

[43]. Huang et al. [44] estimated that the structural responses

under dead load are a vertical deflection of 35 mm, and a beamend rotation of 0.1%.

4. Long length (200500 m)

There are only a few completed long-span HSR bridges in China,

as shown Table 2. The reason is that the main girder of a long-span

bridge is known to be flexible compared to the medium spans. It

can be seen from Table 2 that two existing structural forms are

the steel truss arch and the cable-stayed bridge with truss girder.

4.1. Steel truss arch

A cost-effective steel truss arch should have a main spanbetween 300 m and 400 m. The structural efficiency of the steel

truss arch relies on the strength of each truss member. This form

was first used at the Wuhan-Guangzhou segment in 2009 to span

over the Dongping channel as shown in Fig. 4a. The Dongping

Bridge supported a four-track railway with a span arrangement

of (99 + 242 + 99) m. This truss arch features three main trusses

in the longitudinal direction with a spacing of 14 m, integrated

joints for connecting truss members, the use of high performance

Q370qD (yield strength is 370 MPa) Grade steel and the applica-

tion of an orthogonal steel deck system. Detailed information can

be found in a paper by Liu and Dai [45]. Later, a similar truss arch

was built at the BeijingShanghai segment in 2011 with a longer

span, i.e. the Dashengguan Bridge shown in Fig. 4b. The hybrid

form of truss and arch has also be used, such as the Minjiang BridgeinFig. 4c with a span arrangement of (99 + 198 + 99) m. The key

(a) Kunyang Bridge

(b) Yichang Yangtze Bridge

Fig. 3. Hybrid arch-rigid frame bridges in the HSR of China.

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structural features of steel truss arch bridge are introduced with

the Dashengguan Bridge.

The Dashengguan Bridge supports a six-line railway, includingtwo regular rails, two HSR and two subway lines. A six-span steel

truss with (108 + 192 + 336 + 336 + 192 + 108) m was selected to

provide the large stiffness for such heavy live loads. Similar to

the Dongping Bridge, the three truss planes in the longitudinal

direction was used with a spacing of 15 m. The depth of the truss

arch rib varied from 12 m at the crown to 96 m at the spring line.

Sixteen meter depth uniform truss sections are used at both side

spans. This bridge consumed more than 20.12 tons of Q420qE

Grade steel (yield strength is 420 MPa). The use of a steel box as

the deck system is another feature in the design of this steel truss

arch. This 16 mmthick steel orthogonal plate is adopted as the bot-

tom chord of the entire truss segment to reduce uneven deflection

on the deck. A final design feature presented here is that the hang-

ers of the main span have an octagonal thin-wall cross-section toimprove the aerodynamic characteristics. A seismic analysis for

this structure can be found in a paper by Xia and Zhong[46]. More

detailed structural dimensions can be found in the paper by Gao

et al.[47]. The greatest difficulty encountered during the construc-

tion of the superstructure was the installation of the prefabricated

truss segments. The lifting of the main truss started from the sup-

ports to the mid-span and side span, which is synchronized at

three supports. Four closures for this truss arch includes two atthe end of each side span and two at the crown of the two main

Table 2

Recent completed and ongoing long-span bridges in the HSR of China.

Structural type Bridge name Main span (m) HSR segment Built

Truss arch Dongping 242 Beijing-Guangzhou 2009

Dashengguan 2 336 Beijing-Shanghai 2011

Minjiang 198 Fuzhou-Xiamen 2011

Cable-stayed with truss girder Tianxingzhou 504 Beijing-Guangzhou 2008

Zhengzhou Yellow River 5 168 Beijing-Guangzhou 2010

Yujiang 228 Nanjing-Guangzhou 2011

Tongling Yangtze 630 Hefei-Fuzhou 2013

Anqing Yangtze 580 Nanjing-Anqing 2014 (expected)

Huanggang Yangtze 567 Wuhan-Huanggang 2014 (expected)

Concrete arch Beipanjiang 445 Shanghai-Kunming 2015 (expected)

(a) Dongping Bridge

(b) Dashengguan Bridge

(c) Minjiang Bridge

Fig. 4. Steel truss arch bridges in the HSR of China.

(a) Tianxingzhou Bridge

(b) Yujiang Bridge

(c) Zhengzhou Bridge

Fig. 5. Steel truss cable-stayed bridge in the HSR lines of China.


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spans. The truss segments at the two main spans were lifted by a

cable hoisting system on temporary towers and installed by

70 tons capacity heavy cranes.

4.2. Cable-stayed bridge with truss girder

Cable-stayed bridges with truss girders have been widely used

as long-span HSR bridges in China. It can be seen in Table 2, themain span of the Anqing Bridge and the Tongling Bridge each

exceeded more than 500 m.

The milestone project for the HSR cable-stayed bridge in China

is the Tianxingzhou Bridge (Fig. 5a) that supported four-track traf-

fic and a six-lane highway over the Yangtze River with a span

arrangement of (98 + 196 + 504 + 196 + 98) m. Similar to the

long-span steel truss arch, three 15.2 m uniform-depth truss

planes in the longitudinal direction were used, with a spacing of

15 m in order to improve the torsional stiffness of the cross-section

and the average tensile stress in each truss member. The truss gir-

der has a total length of 1092 m, 14 m per segment for fabrication

and erection. This truss girder consumed more than 43,600 tons of

steel. At the lower level for the HSR lines, the ballast track bed was

adopted. The top chord of the truss segment served as the deck sys-

tem for the motor traffic by using 158 m long concrete plates from

each end of the side span and a 756 m long orthogonal steel plate

for the rest of the main span. The purpose of using a composite sys-

tem is to reduce the unbalanced effect on the piers at the side span

under the live load. Each truss plane on the girder is supported by a

pair of 16 cables for each of the three truss planes (a total of 192

cables) with a total consumption of 4500 tons of steel. The

reinforced concrete tower is 188.5 m tall from the top of pile cap,

consuming 11,240 tons of steel and 44,088 m3 of concrete. A

detailed description can be found in papers by Liu[48], Qin[49],

Zheng and Dai[50].

Since the completion of the Tianxingzhou Bridge, similar spans

have been designed. The Yujiang Bridge in Fig. 5b has a span

arrangement of (36 + 96 + 228 + 96 + 36) m for supporting dou-

ble-track HSR line with a design speed of 300 km/h. The 14 mdepth main girder has two truss planes with a spacing of 15 m.

Fabrication of girder was conducted using 12 m segment. The rein-

forced concrete tower has a height of 105 m. Another example with

a longer span is the Anqing Bridge over the Yangtze River that has

six-spans (101.5 + 188.5 + 580 + 217.5 + 159.5 + 116) m, using

three 15 m depth truss planes with a spacing of 14 m. Fabrication

of girder was conducted using 14.5 m segment. The reinforced con-

crete tower has a height of 210 m. The material consumption on

this bridge is 66,293 t of steel and 53,120 m3 of concrete[51,52].

Some long span bridge designs use a variation from the tradi-

tional cable-stayed bridge with truss girder. For example, the

Zhengzhou Yellow River Bridge is an eight-span extradosed bridge

with six short pylons, supporting six-lanes of motor traffic on the

upper deck and a double-track HSR on the lower deck, as shown

in Fig. 5c. A total of 1684.35 m is divided into eight spans with

(120 + 5 168 + 120) m length to satisfy the required clearance

of the channel. This 14 m depth cross-section has an inverted trap-

ezoid shape with a top width of 24 m and a bottom width of 17 m.

The truss girder is supported by a total of 60 cables. Six 37 m tall

steel pylons stand on the top of the middle truss plane and are rig-

idly connected to the main truss girder at each support. Each pylon

is fabricated in three segments and connected on the bridge site.

The consumption of material includes 26,970 t of steel and

14,109 m3 of concrete. More details on the design and construction

(incremental launching method) can be found in a paper by Gao

[53].

5. Discussion

As discussed above, a large number of long-span bridges for HSR

have been built in China during the past decade. Based on those

examples, it can be seen that the development of medium- and

long-span bridges in China relied on the use of high performance

materials, efficient structural systems and new construction

methods [49,53,54].

High strength steel and high performance concrete have been

widely used in the long-span HSR bridges in China. As discussed

in the medium span section of this paper, high performance con-

crete is commonly used to provide higher strength and durability.

For long span HSR bridges, a steel truss girder is widely used.

Heavy live loads lead to a larger internal force in truss members.

For example, the maximum member force on the Dashengguan

Bridge exceeds 10,000 tons. Thus, two types of steel were devel-

oped to meet this need, including the Q370qE (yield strength is

370 MPa) for relatively lower force members (5500 t).

Two major improvements on the structural system of HSRlong-span bridges in China are the use of a three truss planes main

girder and the use of the orthogonal steel bridge deck.Fig. 6shows

two typical cross-sections of two long-span bridges with three

truss planes. This form has been widely used because these long-

span bridges need to support multiple lines with a heavy live load.

Truss members in these forms can be designed with a smaller size

such that the internal force in each member is lower and the trans-

port of such members is easier. The orthogonal steel deck is also

widely used as a part of the truss system in order to maintain

smoothness on the tracks so that high speed trains can run more

than 200 km/h on the bridges.

Inter-city railwayHSR

15 15

15.

2

6 highway lanes

HSR City railway

1414

(a) Tianxingzhou Bridge (b) Dongping Bridge

Fig. 6. Three truss planes from HSR bridges.

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The construction of these long-span bridges mainly used the

cantilever method, hoisting prefabricated members into position.

The main truss girder is generally divided into segments (typically

1416 m per segment). Other construction method was also avail-

able for special circumstances, such as the incremental launching

method used in the Zhengzhou Yellow River Bridge. Auxiliary facil-

ities that ensured the safety of the bridge, as well as the high speed

trains include: (1) small clips along the main girder and large

expansion devices at the end of main girder to reduce the rotation

of the girder and thus maintain the smoothness of the track; (2)

High strength ball bearings with freedom of movement in all direc-

tions to support large live loads and control the rotation of the gir-

der; (3) a number of magnetorheological (MR) dampers were

installed along the longitudinal direction to reduce the large

dynamic response under earthquake or emergency braking of the

trains [55]; (4) Anti-collision devices and warning lights are

attached to the bridge to avoid collisions.

It is noted that the main span of these HSR bridges are shorter

than some highway bridges. For example, the main span of the

recently completed highway bridge over the Yangtze River in

China exceeded 1000 m. HSR bridges required higher serviceability

limits to ensure an average train speed of 200300 km/h with

much heavier live load than highway bridges. Nevertheless, the

development of new special spans in the future will depend on

the social need, the design competition, new concepts and experi-

ence [56]. Based on the new techniques discussed above, longer

spans have been planned in China with careful feasibility studies.

For example, a cable-stayed bridge with a main span of 1092 m

has been studied for span over the Yangtze River as part of Nan-

tong-Shanghai line that supports both highway and HSR [57]. In

addition, feasibility studies of HSR suspension bridges are being

carried out, such as a bridge at Yangzhou over the Yangtze River

with a main span of 1120 m and a bridge over the Qiongzhou Strait

with a main span of 1408 m.

6. Summary

HSR offers safe, affordable, green transportation that relieves

congestion on highways and traditional railways in China. This

paper presented a brief history of the special spans that support

HSR over rivers and existing lines with a single span more than

100 m. The construction of medium- and long-span HSR bridges

during the past decade is driven by the ongoing development of

the national HSR network. Compared to the design and construc-

tion of standard spans, special spans still require high serviceabil-

ity limits so the trains can maintain high speed on these spans. A

variety of structural forms have been used to meet the deflection

requirements. For medium length, the tied steel arch and the rigid

frame are two commonly used forms. The hybrid system of these

two forms also offers an alternative choice. For large lengths, the

steel truss arch and cable-stayed bridge with truss girder arewidely used. Such progress on the design and construction of spe-

cial spans in the HSR of China depended on the use of advanced

material and construction technologies. Further investigations are

ongoing to establish more comprehensive design specifications

for long-span HSR bridges. The fast development of the HSR

long-span bridges in China are based on learning from experience

of developed countries accumulated in the 20th century. Now, in

turn, China has provided new experience and will continually lead

the construction of HSR long-span bridges in the next decade.

Acknowledgements

The authors gratefully acknowledge the financial support and

first-hand design information provided by China Railway SiyuanSurvey and Design Group CO., LTD. The authors also would like

to acknowledge Dr. William C. Taylor, a civil engineering emeritus

professor from Michigan State University for checking the

language.

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