Railway Continuous Prestressed Concrete Bridge Design In Ballastless .
technologies Article Railway Continuous Prestressed Concrete Bridge Design in Ballastless Track Turnout Zones Wen-Kuei Hsu 1, *, Neng-Hao Shih 2,† and Yu-Lin Lee 3,† 1 2 3 * † Southern Region Engineering Office, Railway Reconstruction Bureau, Ministry of Transportation and Communications, Kaohsiung 81354, Taiwan Central Region Engineering Office, Railway Reconstruction Bureau, Ministry of Transportation and Communications, Taichung 40143, Taiwan; mnhshin@rrbceo.gov.tw Department of Civil Engineering, Chung Hua University, Hsinchu 30012, Taiwan; rosalee@chu.edu.tw Correspondence: mwk hsu@rrbseo.gov.tw These authors contributed equally to this work. Academic Editors: Frédéric Lebon, Raffaella Rizzoni and Manoj Gupta Received: 31 December 2016; Accepted: 23 March 2017; Published: 30 March 2017 Abstract: Laying ballastless track on railway bridges has the advantages of reducing the train noise problem, improving passenger comfort, and reducing track maintenance costs. Therefore, railway bridges with ballastless track have gradually turned into a major trend in railway systems all over the world. In Taiwan, railway bridges with ballastless track have been in use for many years, with ballastless track turnouts also starting to be constructed in recent years. Where railway bridges with ballastless track turnouts are located in urban areas, special consideration must be given to the road crossings and the use of continuous bridges in the turnout zones. Accordingly, there arise a number of difficulties related to the bridge configurations or the continuous length of bridges being excessively long. Often, such situations necessitate the use of extremely large-sized bridge piers in the bridge design, or create the risk of serious damage to the pier structure should insufficient attention be given to any of the factors. This article will take a continuous prestressed concrete bridge as an example. The prestressed concrete bridge must be absolutely continuous, be able to include ballastless track turnout zones, and meet the needs of crossing roads. For this example, the length of the continuous prestressed concrete bridge is over 300 m. This article will also discuss the configuration of a continuous prestressed concrete bridge of railway, and—through the analysis of track–bridge interaction and temperature detection—provides suggestions on the optimal configuration model of the continuous prestressed concrete bridges, which should allow improper configuration and possible structural damage to be avoided. Keywords: railway bridge; continuous prestressed concrete bridge; ballastless track; turnout zone; track buckling 1. Introduction To effectively use urban land and address various urban transport problems, in recent years the government of Taiwan has been promoting the use of elevated railway systems in urban areas, as shown in Figure 1. Since most urban railways are located adjacent to densely-populated residential and commercial areas, noise and vibration reduction becomes an important issue after the commencement of railway viaduct operation. Laying ballastless track has become a basic need in railway viaduct projects due to the importance of train noise reduction, improvement of passenger comfort, and the need to minimize the track maintenance costs. Technologies 2017, 5, 11; doi:10.3390/technologies5020011 www.mdpi.com/journal/technologies
Technologies 2017, 5, 11 2 of 9 Technologies 2017, 5, 11 2 of 9 Figure 1. Urban elevated railway project in Taiwan. Figure 1. Urban elevated railway project in Taiwan. An elevated urban railway system usually contains general railway bridges, elevated railway stations, andurban turnoutrailway zone bridges both ends of the general elevated railway railway station. Aselevated previously An elevated systematusually contains bridges, railway mentioned, when configuring continuous prestressed concrete bridges, we must consider crossing stations, and turnout zone bridges at both ends of the elevated railway station. As previously roads and adopting continuous bridge prestressed in the turnout zone. This oftenwe leads to consider bridge span mentioned, when configuring continuous concrete bridges, must crossing configuration issues and problems related to the bridge length being too long. These situations roads and adopting continuous bridge in the turnout zone. This often leads to bridge span necessitate the use of very large-sized bridge piers in the railway bridge design, and create the risk configuration issues and problems related to the bridge length being too long. These situations of structural damage. necessitateThis the use of will verytherefore large-sized bridge piers in theforrailway bridge design, and create the risk of article recommend solutions continuous prestressed concrete bridge structural damage. design in turnout zones, and continuous length over 300 m. It will suggest the configuration essentials continuous prestressed concrete bridgefor design in turnout zones through an analysis This articleofwill therefore recommend solutions continuous prestressed concrete bridgeofdesign temperature and various typesover of bridge load. willthe alsoconfiguration discuss the structural in turnout zones, changes and continuous length 300 m. It The willarticle suggest essentials of characteristics of continuous bridges, the effects of various loading types on continuous bridges, continuous prestressed concrete bridge design in turnout zones through an analysis of temperature and will consider some important points on continuous bridge design which allow structure changes and various types of bridge load. The article will also discuss the structural characteristics damage problems to be minimized. of continuous bridges, the effects of various loading types on continuous bridges, and will consider some 2. important on continuous bridge design which allow structure damage problems to Ballastlesspoints Track Turnout Layout Theory be minimized. 2.1. Turnouts and Bridge Configuration 2. Ballastless Track Turnout Layout Theory As the train speed increases, the viaduct railway with a ballastless track becomes an increasingly important factor in the safety and stability of railway operation, and the deformation 2.1. Turnouts and Bridge Configuration requirements of ballastless track turnout structure become more and more stringent. Therefore, there a number of strict rules restrictions when it comes to the configuration of an ballastless As the are train speed increases, theand viaduct railway with a ballastless track becomes increasingly track turnouts on the railway viaduct. important factor in the safety and stability of railway operation, and the deformation requirements of ballastless track turnout structure become more and more stringent. Therefore, there are a number 2.1.1. Avoid the Bridge Expansion Joint on Ballastless Track Turnout Zone of strict rules and restrictions when it comes to the configuration of ballastless track turnouts on the Bridge expansion joints should not be installed in the railway viaduct’s ballastless track railway viaduct. turnout zone, and continuous bridge configuration in the ballastless track turnout zone must conducted. If the configuration be Ballastless performed for the continuous bridge, design of the bridge 2.1.1. Avoid the Bridge Expansion cannot Joint on Track Turnout Zone expansion plate should contain a hinge at the bridge expansion joints in order to meet the Bridge expansion joints should benot installed viaduct’sjoints. ballastless track turnout requirement that the turnout zone not must be set upinatthe therailway bridge expansion In addition, the relative displacement a bridge expansion can cause zone, and continuous bridge configuration inof the ballastless track joint turnout zone track mustdisplacement conducted. If the or turnout damage, so the bridge expansion joint with turnout switch blades must be kept at a plate configuration cannot be performed for the continuous bridge, design of the bridge expansion certain distance (denoted as “d” in Table 1 below). The d values are recommended in Table 1, in should contain a hinge at the bridge expansion joints in order to meet the requirement that the turnout which L indicates the expansion length of the bridge [1]. zone must not be set up at the bridge expansion joints. In addition, the relative displacement of a bridge expansion joint can cause track displacement or turnout damage, so the bridge expansion joint with turnout switch blades must be kept at a certain distance (denoted as “d” in Table 1 below). The d values are recommended in Table 1, in which L indicates the expansion length of the bridge [1].
Technologies 2017, 5, 11 3 of 9 Table 1. Relationship of bridge expansion length L and d values. Technologies 2017, 5, 11 3 of 9 L 60 m d 7m Table 1. Relationship bridge 60 m of L 90 mexpansion d length 17 mL and d values. dd 7 27 mm 60 m L 90 m d 17 m L d larger 27 m values are required: For the bridge expansion length (L), 90 themfollowing 90 m Lm L 60 (1) (2) Forfixed the bridge lengthsupport (L), the following are required: Bridge pointexpansion and movable of simplelarger spanvalues or multi-span bridge. The distance between two adjacent bridges of bridge fixed points. In short, a complex bridge (1) Bridge fixed point and movable support of simple span or multi-span bridge. type candistance be simplified a simple to determine bridge expansion length L. (2) The betweento two adjacent beam bridgesmodel of bridge fixed points.the In short, a complex bridge type can be to a simple beam model on to determine the bridge expansion length L.to axial The decision of simplified a simple beam model depends the main bridge structure subjected The decision of a simple beam model depends on mainaxial bridge structure subjected to axial deformation of temperature change. According to the bridge deformation restraints, decide the deformation of temperature change. According to bridge axial deformation restraints, decide fixed bearing positions and movable bearing positions, shown in Figure 2. the fixed bearing positions and movable bearing positions, shown in Figure 2. Bridge expansion joint length L1 L2 L3 90m L2 L3 L1 Bridge span Turnout Zone 7 FF M 27 MF M Bridge fixed point L1 L2 /2 60m Bridge expansion joint length L1 Bridge span L2 /2 L3 60m L2 L3 Turnout Zone 7 FM F 7 F MF Bridge fixed point Bridge expansion joint length L1 L2/2 60m L1 Bridge span 7 FM L2/2 L3 L4 L5/2 90m L2 L3 Turnout Zone F L4 27 F L5 L6 Turnout Zone 27 F MM Bridge fixed point L5/2 L6 60m F 7 M F Bridge fixed point Figure 2. Expansionlengths lengths Calculation Calculation ofofdifferent bridge configurations. Figure 2. Expansion different bridge configurations. Avoid Configuring Continuous Long-Span Bridges 2.1.2. 2.1.2. Avoid Configuring Continuous Long-Span Bridges Usually, laying ballastless track is accompanied by the adoption of continuous welded rail. For Usually, laying ballastless track is accompanied by the adoption of continuous welded rail. continuous long-span bridges, it is easy to cause resistance to rail longitudinal accumulation force For continuous bridges, it is resistance to raillong-span longitudinal accumulation and exceed long-span the allowable limits of theeasy rail.to So,cause configured continuous bridges should be force and exceed of the rail. So,Ifconfigured continuous long-span should be avoidedthe in allowable ballastless limits track turnout zone. these cannot be avoided, the rails bridges under high temperature axial track force or the fractured openings at low be temperature beunder reviewed, rail avoided in ballastless turnout zone. If these cannot avoided, should the rails highand temperature expansion joints must beopenings set if necessary axial force or the fractured at low[2,3]. temperature should be reviewed, and rail expansion joints must be set if necessary [2,3]. 2.2. Effect of Temperature Difference between Bridge and Track System 2.2. Effect For of Temperature between and Track System concrete bridge, it should be ballastless Difference track turnout on aBridge continuous prestressed remembered that changes of temperature, rails, and bridges may be restricted by boundary For ballastless track turnout on a continuous prestressed concrete bridge, it should be remembered that changes of temperature, rails, and bridges may be restricted by boundary conditions. Due to the
Technologies 2017, 5, 11 4 of 9 difference in the coefficients of thermal expansion of rails and bridges, track longitudinal forces are created between rails and bridges. For ballastless track, the strength of longitudinal force between Technologies 2017, 5, 11 4 of 9 rails and bridges is determined by the rail fastening clip. In addition, bridges produce contraction by temperature variation the restraint bridge supports. interaction between conditions. Due to and the difference in theofcoefficients of thermalThe expansion of railsbehavior and bridges, track rails and bridges becomes complicated. It is important that tracks and bridge structures must be longitudinal forces are created between rails and bridges. For ballastless track, the strengthcarefully of longitudinal force between rails andrail bridges is determined by track’s the rail longitudinal fastening clip.direction In addition, configured in order to properly control axis forces along the to avoid bridges problems produce contraction by temperature variation and the restraint of bridge supports. The rail buckling [4]. interaction behavior between rails and bridges complicated. It isthe important thatof tracks and Accordingly, when laying ballastless trackbecomes on railway bridges, influence track–bridge bridge structures must be carefully configured in order to properly control rail axis forces along the interaction must be carefully evaluated and reviewed, including the following aspects [5]: track’s longitudinal direction to avoid rail buckling problems [4]. (1) (2) (3) (4) (5) Accordingly, whenoflaying railway bridges, the influence of track–bridge Proper configuration bridgeballastless supportstrack and on bridge spans. interaction must be carefully evaluated and reviewed, including the following aspects [5]: Inspection of fixed support of bridge while continuous welded rails produce maximum (1) Proper configuration of bridge supports and bridge spans. longitudinal force. (2) Inspection of fixed support of bridge while continuous welded rails produce maximum Inspection of track buckling stability at maximum temperature. longitudinal force. Inspection of track fractured opening at minimum temperature. (3) Inspection of track buckling stability at maximum temperature. The up of requirements ofopening rail expansion joints or protective device. (4) setting Inspection track fractured at minimum temperature. (5) The setting up requirements of rail expansion joints or protective device. 3. Continuous Prestressed Concrete Bridge Design in Ballastless Track Turnout Zone 3. Continuous Prestressed Concrete Bridge Design in Ballastless Track Turnout Zone 3.1. Configuration of the Continuous Prestressed Concrete Bridges 3.1. Configuration of the Continuous Prestressed Concrete Bridges The article takes a continuous prestressed concrete bridge as an example. The bridge configuration The article takes a continuous prestressed concrete bridge as an example. The bridge satisfies both the requirements of having street-level road crossings and of adopting an absolutely configuration satisfies both the requirements of having street-level road crossings and of adopting continuous bridge in the turnout zone conditions. Figure 3 represents a common case of railway an absolutely continuous bridge in the turnout zone conditions. Figure 3 represents a common case viaduct bothviaduct ends ofonthe railway station. of on railway both ends ofviaduct the railway viaduct station. Figure 3. The span configurations of continuous prestressed concrete bridges consider with the Figureturnout 3. The group span configurations continuous prestressed concrete bridges consider with the turnout and crossing theof road. group and crossing the road. The plan of Figure 3 shows the turnout group installed continuously, the space is too close to appropriately set bridge expansion joints. Ingroup addition, the profile diagram shows that the The plan of Figure 3 shows the turnout installed continuously, the space is bridge too close to must step over the intersection road and configure a large-span bridge by demand. The above appropriately set bridge expansion joints. In addition, the profile diagram shows that the bridge factors make this section of prestressed concrete continuous bridge longer than 300 m, and it has an must step over the intersection road and configure a large-span bridge by demand. The above factors irregular configuration of bridge structures. For this configuration type of continuous prestressed make this section of prestressed bridge longer than 300 m, and it has an irregular concrete bridge, the followingconcrete situationscontinuous should be considered: configuration of bridge structures. For this configuration type of continuous prestressed concrete bridge, the following situations should be considered:
Technologies 2017, 5, 11 5 of 9 3.1.1. Bridge Expansion Joint Setting, the Turnout Layout Requirements Technologies 2017, 5, 11 5 of 9 Because the train load is larger, the depth-to-span ratio of continuous prestressed concrete bridges 3.1.1. Bridge Expansionwith Joint the Setting, thelong-span Turnout Layout Requirements is about 1/12. Compared same highway bridge, the depth of the railway bridge beam is twice as the large. the railway viaduct goes through downtown areas, concrete to avoid the Because trainBecause load is larger, the depth-to-span ratio of continuous prestressed bridge volume causing much pressure, in addition to the considerations of crossing intersection bridges is about 1/12.too Compared with the same long-span highway bridge, the depth of the railway bridge beam is twice as large. Because the railway viaduct goes downtown areas, to avoid roads, general bridge spans should be configured in 25–35 m.through In addition to the reason that the the bridge volume causing too much pressure, in addition to the considerations of crossing bridge superstructure size is large and the bridge section stiffness is relatively large. For the bridge intersectionspecial roads, general bridge spans should in 25–35 m. (1) In addition to the reason configurations, attention needs to be paid be to configured the following issues. The length of continuous that the bridge superstructure size is large and the bridge section stiffness is relatively large. For the the bridges should not be too long, as it creates prestress losses and is difficult to design. (2) With bridge configurations, special attention needs to be paid to the following issues. (1) The length of influence of temperature (which causes great force to be applied to the pier), the pier design becomes continuous bridges should not be too long, as it creates prestress losses and is difficult to design. (2) especially difficult. Therefore, when the continuous length of the railway bridge is too long, it must be With the influence of temperature (which causes great force to be applied to the pier), the pier design divided into different thesewhen bridge mustlength be connected at the bridge’s becomes especially bridge difficult.units; Therefore, thedecks continuous of the railway bridge is tooexpansion long, joints.it Our suggestions for the support of the continuous bridge configuration are shown in Figure 2; must be divided into different bridge units; these bridge decks must be connected at the bridge’s the suggestions are provided in orderfortothe match the of requirements that turnout does not set a bridge expansion joints. Our suggestions support the continuous bridge configuration are up shown in Figure 2; the suggestions are provided in order to match the requirements that turnout does not expansion joint. set up a bridge expansion joint. 3.1.2. Multi-Span Continuous Bridge Structural Design 3.1.2. Multi-Span Continuous Bridge Structural Design This section will discuss the bridge configuration in Figure 3 as an example. The bridge structure Thisthrough section awill discuss the bridge configuration in Figure 3 asmechanical an example.characteristics The bridge of is analyzed variety of bridge loads. The discussion of the structure is analyzed through a variety of bridge loads. The discussion of the mechanical a continuous prestressed concrete bridge and a description of bridge design includes: (1) hinged characteristics of a continuous prestressed concrete bridge and a description of bridge design plate design of continuous prestressed concrete bridge; (2) supporting configuration of continuous includes: (1) hinged plate design of continuous prestressed concrete bridge; (2) supporting prestressed concrete in turnout zone; (3) design of continuous prestressed concrete bridge piers. configuration of bridges continuous prestressed concrete bridges in turnout zone; (3) design of continuous prestressed piers. prestressed concrete bridge (1) Hinged plateconcrete design bridge of continuous (1) Hinged plate design of continuous prestressed concrete bridge To design the hinged plate of continuous prestressed concrete bridges, the bridge structure of To design the hingedfirst, plateand of continuous prestressed concrete bridges, the be bridge structure of the Figure 2 must be analyzed the requested load specification must applied. Then, Figureinternal 2 must be analyzed and plates the requested specification must be applied. Then, the maximum forces of thefirst, hinged must beload calculated. maximum of the hinged plates be calculated. For hingedinternal plates,forces temperature change on amust hinged slab has the most significant axial force effects, For hinged plates, temperature change on a hinged slab has the most significant axial force followed by creep and shrinkage (maximum axial forces caused in about 3000 days after the bridge effects, followed by creep and shrinkage (maximum axial forces caused in about 3000 days after the construction was completed). The influences of temperature, creep, and shrinkage on the overall bridge construction was completed). The influences of temperature, creep, and shrinkage on the bridge structure indicated in Figurein4.Figure Figure4. 4Figure shows that the range of maximum axial force is overall bridgeare structure are indicated 4 shows that the range of maximum axial close force to pier stiffness center or the bridge fixed point position. Hinged plate A is located in the range is close to pier stiffness center or the bridge fixed point position. Hinged plate A is located in of maximum axialofforce. It should designed to adopt the maximum axial According analysis the range maximum axialbeforce. It should be designed to adopt theforce. maximum axial to force. results, the axialtoforces ofresults, hingedthe plate are significantly smaller. According analysis axialB forces of hinged plate B are significantly smaller. Temperature, creep and shrinkage caused by contraction of the bridge Temperature, creep and shrinkage caused by contraction of the bridge Bridges maximum axial force range hinged plate A hinged plate B bridge fixed point Pier stiffness center P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 Resistance to temperature, creep and shrinkage of contractions, pier on the bridge produces reaction forces Temperature, creep and shrinkage of contractions pull, bridge pier generated force Figure 4. Temperature, creep, effectson onthe theoverall overall bridge structure. Figure 4. Temperature, creep,and andshrinkage shrinkage effects bridge structure. For hinged plate A, structural analysis results of axial force are shown in Table 2. The total For hinged plate A, structural analysis results of axial force are shown in Table 2. The total maximum axial force is 622.66 t. A detailed design drawing of hinged plate A is shown in Figure 5. maximum axial force is 622.66 t. A detailed design drawing of hinged plate A is shown in Figure 5.
Technologies 2017, 5, 11 6 of 9 Technologies 2017, 5, 11 of 9 According to the structure size and reinforcement quantity in the detailed design drawing, 6the calculation and evaluation of resistance axial force safety factor is as follows: According to the structure size and reinforcement quantity in the detailed design drawing, the calculation and evaluation of resistance axial force safety factor is as follows: Hinged plate A size: 690 cm 20 cm Hinged plate A size: 690 cm 20 cm Steel reinforcement configuration: 2-D19@12.5 cm Steel 2-D19@12.5 cm Steelreinforcement reinforcementconfiguration: quantity: 216 bars Steel reinforcement quantity: 216 bars Steel reinforcement allowed tension stress As * 0.4 * Fv 216 * 2.87 * 0.4 * 4.2 1041.46 t Steel reinforcement allowed tension stress As * 0.4 * Fv 216 * 2.87 * 0.4 * 4.2 1041.46 t Neglect concrete cracking tension. Neglect concrete cracking tension. Hinged plate A resistance axis force safety factor (SF) 1041.47/622.66 1.67 Hinged plate A resistance axis force safety factor (SF) 1041.47/622.66 1.67 Table 2. The axial force analysis of hinged plates by major bridges loading. Table 2. The axial force analysis of hinged plates by major bridges loading. 365 Days Factors Affecting the Hinge Plate Main Load Factors Affecting the Hinge Plate Main Load Axial Force (t) Temperature Temperature Creep Creep Shrinkage Shrinkage Summation Summation 0.00 0.00 0.00 3000 Days 3000 Days Accumulated 365 Days Accumulated Axial Axial ForceForce (t) Axial Force (t) Force Axial (t) Axial (t)Force (t) 0.00 315.78 315.78 315.78 315.78 0.00 174.75 174.75 174.75 174.75 0.00 132.13 132.13 132.13 132.13 622.66 622.66 Figure5.5.Hinged Hingedplate plateAAdetailed detaileddesign. design. Figure (2) Supporting configuration of continuous prestressed concrete bridges in turnout zone (2) Supporting configuration of continuous prestressed concrete bridges in turnout zone As shown in Figure 3, for the continuous prestressed concrete bridge to satisfy the condition of As shown in Figure 3, for the continuous prestressed concrete bridge to satisfy the condition of not setting up bridge expansion joint in the turnout zone, as shown in Figure 6, it is recommended not setting up bridge expansion joint in the turnout zone, as shown in Figure 6, it is recommended that support configurations be such as indicated in Figure 2. Piers P2–P10 are configured with fixed that support configurations be such as indicated in Figure 2. Piers P2–P10 are configured with fixed support, and piers P1 and P10 are configured with movable support. At both ends of the continuous support, and piers P1 and P10 are configured with movable support. At both ends of the continuous prestressed concrete bridges of the adjacent bridge of the first support need to configure a fixed prestressed concrete bridges of the adjacent bridge of the first support need to configure a fixed support. support. In this configuration, the pier P1 in Figure 3, the bridge expansion length (L) formula is as In this configuration, the pier P1 in Figure 3, the bridge expansion length (L) formula is as follows: follows: L L 25 mm 25 mm 2525mm 3030mm 3030mm 30 25 25 30m/2 m/2 150 m 90 m Thus,ititisissuggested suggested that turnout switch blade distance pier P1 expansion Thus, that thethe turnout switch blade distance from from bridgebridge pier P1 expansion joints joints need to keep a distance of 27 m or more. The allowable bearing capacity of the support design need to keep a distance of 27 m or more. The allowable bearing capacity of the support design is is recommended above configuration order executethe theoverall overallbridge bridgestructure structureanalysis analysis recommended as as thethe above configuration in in order totoexecute andcalculate calculatethe thebearing bearingcapacity capacityof ofeach eachsupport. support. Finally, Finally,the thebridge bridgesupports supportsare aredesigned designedby bythe the and analysis results. analysis results.
Technologies 2017, 5, 11 Technologies 2017, 5, 11 Technologies 2017, 5, 11 7 of 9 7 of 9 7 of 9 Figure 6. Cannot set up bridge expansion joint in the turnout zone. Figure 6. 6. Cannot Cannot set set up up bridge bridge expansion expansion joint joint in in the the turnout turnout zone. zone. Figure (3) Design of continuous prestressed concrete bridge piers (3) Design Designofofcontinuous continuousprestressed prestressed concrete bridge piers concrete bridge piers Generally, in the structural design of the bridge, the pier design is controlled by the seismic Generally, of theofbridge, the pier is controlled by is in the structural design designcontinuous thelonger, seismic force of load combinations. When the length a prestressed concrete bridge force of load combinations. When the length of a prestressed concrete continuous bridge is the length of a prestressed concrete continuous longer, the structural stiffness of When the bridge superstructure is greater than the pier. Bothbridge ends is oflonger, the thecontinuous structuralstiffness stiffness the bridge superstructure is greater the ends of athe bridge piers may be controlled by theis temperature load and make structural of of the bridge superstructure greater than of thethan pier.combinations, Bothpier. endsBoth of the continuous continuous bridge mayends bebycontrolled by the temperature of andvisual make a largerpiers lateral force at both of bridge piers. Therefore, in load pier combinations, design, to achieve bridge may bepiers controlled thethe temperature of load combinations, and make a larger lateral consistency of the adjacent piers, isTherefore, suggested that there can b
This article will therefore recommend solutions for continuous prestressed concrete bridge design in turnout zones, and continuous length over 300 m. It will suggest the configuration essentials of continuous prestressed concrete bridge design in turnout zones through an analysis of temperature changes and various types of bridge load.
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