ARGENTINE CONNECTION BRIDGE TRIPLE TRACK CROSSING. Kansas City Terminal Railway Company

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1 James P. Hyland Page 1 ARGENTINE CONNECTION BRIDGE TRIPLE TRACK CROSSING Kansas City Terminal Railway Company James P. Hyland, P.E. Senior Bridge Engineer TranSystems Corporation

2 James P. Hyland Page 2 Argentine Connection Bridge Triple Track Crossing James P. Hyland The Argentine Connection Project will mark the completion of the second triple track crossing in the United States. The purpose of this paper is to discuss the reasons for the project, the main double track bridge, the unique cross girders and the unique geological conditions of the project. The Argentine Connection Project is a two mile rail project in a highly congested rail area utilized by several hundred trains per day. The project includes two new bridges, embankment construction, rock excavation and several retaining walls. The main bridge is a double track bridge, 2,480 feet in length, spanning two at-grade north-south Burlington Northern Santa Fe (BNSF) mainline tracks, three at-grade east-west Kansas City Terminal tracks (Low Line), two elevated east-west Kansas City Terminal tracks (High Line Bridge), and one existing double-cell 17-foot by 17-foot box culvert. The main bridge consists of eight steel deck girder spans and 23 prestressed concrete deck girder spans with cast-in-place concrete decks supported on concrete piers with steel piles or drilled shafts. Three piers required the use of steel cross girder boxes to support the superstructure. The second bridge consists of two 80-foot spans over an existing six lane road utilizing a combination of steel deck girders and prestressed concrete deck girders supporting six tracks and a maintenance road. Key Words: bridge design, steel railway bridge, triple track crossing, concrete railway bridge

3 James P. Hyland Page 3 ARGENTINE CONNECTION BRIDGE TRIPLE TRACK CROSSING Kansas City Terminal Railway Company INTRODUCTION The Kansas City Metropolitan area is the second busiest railroad center in the United States. The main crossing diamonds of the east-west mainline Kansas City Terminal (KCT) tracks and northsouth BNSF Fort Scott Subdivision mainline tracks have reached their capacity and can no longer provide efficient train operations. The result is a major bottleneck in the Kansas City Metropolitan area. The Argentine Connection Project will ease the rail congestion through this bottleneck. Over 125 train movements are made daily over the main crossing diamonds by all of the railroads in the Kansas City area. While the majority of these are BNSF movements, the Union Pacific Railroad (UPRR) also has a considerable amount of traffic. The current situation is similar to placing a four-way stop on an interstate highway. The Argentine Connection Project will enable BNSF trains that run through Kansas City to flyover the main crossing diamonds and the High Line Bridge. This will remove 60 trains daily from the choke point and enable more efficient movement of the remaining trains. The project will also reconfigure the at-grade Low Line tracks, the main crossing diamonds, and their connections. This reconfiguration will significantly improve train speeds on the Low Line tracks with speeds increasing from 15 mph to 30 mph.

4 James P. Hyland Page 4 Figure 1 Aerial Photo of Argentine Connection Bridge Picture is looking west. The High Line Bridge is the curved bridge in the photo. Left of the High Line Bridge are the three Low Line tracks. BNSF Fort Scott Subdivision tracks cross from lower left to upper right of the photo. The new Argentine Connection Bridge is under construction in the middle of the photo. Concept: The Argentine Connection Project is located at the KCT s Santa Fe Junction. Upon completion, it will be a double track alignment having a length of 9,300 feet connecting BNSF s Argentine Yard on the west, with the KCT mainline tracks on the east. The west touchdown will be located near the existing Seventh Street Bridge in Kansas City, Kansas, and the east touchdown will be located near the Southwest Boulevard Bridge in Kansas City, Missouri. The Argentine Connection Project will provide parallel double track train movements. In addition, major elements of the project include:

5 James P. Hyland Page 5 Earthen embankment approaches. A flyover bridge Argentine Connection Bridge over the existing KCT Low Line tracks, KCT High Line Bridge tracks, and BNSF Fort Scott Subdivision tracks (see Figure 1). Replacement of the existing Southwest Boulevard Bridge. Reconfiguration of the KCT Low Line and BNSF Fort Scott Subdivision tracks and associated connections. This paper focuses on only one of these major elements, the flyover bridge and its unique elements of design and construction. BRIDGE DESIGN & CONSTRUCTION Argentine Connection Bridge The Argentine Connection Bridge is a double track bridge, 2,480 feet in length, spanning two atgrade north-south Burlington Northern Santa Fe (BNSF) Fort Scott Subdivision mainline tracks, three at-grade east-west Kansas City Terminal tracks (Low Line), two elevated east-west Kansas City Terminal tracks (High Line Bridge), and one existing double-cell 17-foot by 17-foot box culvert. The bridge is divided into three units from east to west. Units 1 and 3 were originally two separate bridges with new embankment between these units. Unit 2 was added due to the anticipated excessive settlement of an existing 40-foot thick layer of clay, caused by the addition of 30 feet to 40 feet of embankment. The substantial time required for consolidation of this clay layer would have adversely affected the construction schedule.

6 James P. Hyland Page 6 The bridge superstructure consists of eight steel deck girder spans and 23 precast prestressed concrete deck girder spans with cast in-place concrete decks. Each superstructure span consists of four girders per track with metal walkways and handrails on each side of the bridge. The superstructure is typically supported on concrete piers with steel piles or drilled shafts. There are, however, three unique substructure elements consisting of steel cross girder boxes. These cross girder boxes are supported on concrete caps and columns. Two of the three cross girder boxes are supported on footings with steel piles and the other one is supported on drilled shafts. Steel Cross Girder Boxes The three steel cross girder boxes span over three main obstacles of the project. The first steel cross girder spans over the OK Creek Sewer, which is an existing double-cell 17-foot by 17-foot box culvert (see Figure 2). The OK Creek Sewer crosses the project alignment at a severe angle requiring a unique solution. The solution is a steel cross girder box normal to the main alignment spanning over the OK Creek Sewer supporting two tracks with a split superstructure. The split superstructure allows the piers up-station and back-station of the cross girder to be staggered around the existing box culvert, accommodating the severely skewed alignment. Three of the four superstructure spans supported on the cross girder are precast prestressed concrete girder spans with the fourth being a steel deck girder span. The other unique aspect of this cross girder is that the superstructure is supported on top of the cross girder box with Teflon sliding bearings. The bearings for the longitudinal girders are centered over the webs of the steel cross girder box. The cross girder itself is supported on reinforced elastomeric bearings. The cross girder bearings are supported on concrete caps, columns and footings with steel piles.

7 James P. Hyland Page 7 Figure 2 Cross Girder over OK Creek Sewer The second steel cross girder spans over the High Line Bridge, which carries east-west Kansas City Terminal traffic (see Figure 3). The Argentine Connection Bridge crosses the High Line Bridge both at a skew and requiring minimal structure depth. The small structure depth required the steel cross girder to be placed normal to the High Line Bridge and skewed to the Argentine Connection Bridge. Unlike the other steel cross girders, minimizing the structure depth of the cross girder requires the longitudinal girders to be supported on saddles bolted to the sides of the cross girder. Each saddle consists of a U-shaped bent plate with a solid block in the bottom (see Figure 4). The U-shaped bent plate is bolted to the cross girder with bent plate angles. The longitudinal girders are supported on Teflon sliding bearings. The cross girder is supported on

8 James P. Hyland Page 8 reinforced elastomeric bearings. The cross girder bearings are supported on concrete caps, columns and footings with steel piles. Figure 3 Cross Girder over High Line Bridge

9 James P. Hyland Page 9 Figure 4 Cross Girder Saddle The third steel cross girder spans over the three at-grade east-west Low Line Tracks (see Figure 5). These tracks cross under the Argentine Connection Bridge at a skew, although this pier is normal to the Argentine Connection Bridge due to the length of the spans supported. A unique aspect of this cross girder is that the superstructure is supported on top of the cross girder box with Teflon sliding bearings. Like the OK Creek Sewer cross girder, the bearings for the longitudinal girders are centered over the webs of the steel cross girder box; and the cross girder is supported on reinforced elastomeric bearings. The cross girder bearings are supported on concrete caps, columns and drilled shafts. This steel cross girder is the largest of the three cross girders weighing approximately 185,000 pounds and having a web height of 10-6 and flange widths of 5-0.

10 James P. Hyland Page 10 Figure 5 Cross Girder over Low Line Tracks Subsurface Characteristics The project site has highly variable subsurface conditions over the two mile project length. The eastern end of the project begins in the remnants of the OK/Turkey Creek floodplains. As the project heads west, it progresses towards the Kansas River floodplain and then goes through a rock bluff that forms the south valley wall of the Kansas River, and then continues south along the edge of the Kansas River floodplain on the west end of the project. The geology in the project site is quite complex and is constantly being evaluated by geologists in the Kansas City area.

11 James P. Hyland Page 11 The OK/Turkey Creek valley is believed to be the result of glacial activity about 500,000 years ago. As the glacier pushed further south, the Missouri River was pushed south, causing lobes from the Kansas ice sheet to block both the Kansas and Missouri Rivers. This lobe acted as a dam creating large lakes. Drainage from these lakes was diverted through outlet channels that breached low divides between the Kansas River and Turkey Creek. The melting glacier formed a deep, narrow channel eroded in the existing bedrock. After the glacier melted, the Kansas River resumed its original course. The deep channel was then filled with a mixture of clays, silts, and sands/gravels to depths varying from quite shallow to over 250 feet deep within this valley. It is believed that this valley crosses the Argentine Connection Bridge in Units 1, 2 and the eastern part of Unit 3. The subsurface characteristics of the Argentine Connection Bridge consist of four distinct areas, split among the three units of the bridge. These areas typically follow the individual units, except Unit 3, which has two distinct areas. The geology of Unit 1 consists of rock varying from 100 feet to 140 feet below the ground. This geology required the use of H-piles driven to rock to support the bridge as drilled shafts would not have been economical. Unit 2 typically has rock about 140 feet from the ground except where the rock falls off to around 250 feet in the valley previously described. Another unique feature of Unit 2 is the presence of boulders about 60 feet to 70 feet below the ground. The presence of these boulders was discovered during pile driving. Once discovered, dynamic pile analysis was completed on some of the piles known to be bearing on boulders. The analysis revealed that the original pile driving criterion developed for the project, achieves the required capacity for the piles bearing on

12 James P. Hyland Page 12 boulders. However, additional pile driving criteria was required to address longer piles being driven adjacent to these short piles. The additional criteria required the contractor to retap any short driven pile if an adjacent pile was driven deeper. The original pile driving criteria is utilized when retapping any pile. The result of this unique geology was piles that varied from 60 feet to 250 feet, some of which were even within the same footing. Unit 3 is broken up into two distinct areas east and west. The east area geology consists of rock varying between 120 feet to 155 feet below the ground. This geology allows for the use of H-piles driven to rock to support the bridge. The geology of the west area is part of the south valley wall of the Kansas River and has rock around 50 feet below the ground. This geology allows for the use of drilled shafts supported on the rock. TRIPLE TRACK CROSSING Upon completion of the Kansas City Terminal Railway Company s Argentine Connection Project, the second three-level railroad crossing in the United States will be born. The other is still in use today in Richmond, Virginia supporting tracks of three railroads the Southern, the Seaboard, and the Chesapeake and Ohio intersecting at three separate levels (see Figure 6). Richmond s triple track crossing was completed in Since then the three railroads have staged trains at the crossing only three times: in 1911 and 1926 with steam engines and in 1949 with diesel engines. This staging of trains from all three railroads has been extremely difficult. In Kansas City, however, staging of trains will not be required. This is because the rail traffic on all three levels (the High Line Bridge, Low Line tracks and the Argentine Connection tracks) is controlled by the Kansas City Terminal; and the frequency of three trains

13 James P. Hyland Page 13 crossing, one at each level simultaneously, may be a daily occurrence in Kansas City. The frequency of this and the sheer volume of trains crossing the area highlight the necessity and value of the Argentine Connection Project. Completion of this project in September 2004 will significantly ease rail congestion in the Kansas City area. Figure 6 Richmond, Virginia Triple Track Crossing Used with permission by Larry Z. Daily