Joint-less Continuous Curved Steel Girder Structure

Harold Fink, PE

New York City Region

New York State Department of Transportation

47-40 21st Street

Long Island City, NY 11101

T) 718-482-4725

F) 718-482-6319

Harold.Fink@dot.ny.gov

Richard Wenke, PE

New York State Department of Transportation

50 Wolf Road

Albany, NY 12232

T) 518-457-9166

F) 518-457-6827

Richard.Wenke@dot.ny.gov

Michael D. Liona, PE

Hardesty and Hanover

1501 Broadway

New York, NY 10036

T) 212-944-1150

F) 212-391-0297

mliona@hardesty-hanover.com

Rasmin Kharva, PE

Hardesty and Hanover

1501 Broadway

New York, NY 10036

T) 212-944-1150

F) 212-391-0297

rkharva@hardesty-hanover.com

Harold Fink and Richard Wenke are the corresponding authors

Submission Date: November 14, 2013

2,114 words (not including Title Page) plus 8 figures @ 250 words each = 4,114

TRB 2014 Annual Meeting Paper revised from original submittal.

P a g e | 1

ABSTRACT

A new structure was designed to be fully joint-less to eliminate typical deck joints which are costly to

maintain and are a main cause of superstructure and substructure deterioration. At a length of

approximately 800 feet, this 4-span continuous curved steel girder bridge will be the longest fully joint-

less structure owned by NYSDOT when completed. Finite element modeling was used to determine the

full range of thermal movements of the structure taking into account thermal gradients. Specific details

were developed to accommodate these movements. The details included use of an asphalt pressure relief

joint, sleeper slab and grade beams.

Introduction

The New York State Department of Transportation (NYSDOT) is progressing a series of construction

contracts to address highway operational, structural, and safety deficiencies in the Kew Gardens

Interchange of Queens, New York. This interchange contains several major highways including – the Van

Wyck Expressway (VWE), Union Turnpike (UTP), the Grand Central Parkway (GCP) and the Jackie

Robinson Parkway (JRP). These facilities handle a combined traffic volume of over 250,000 vehicles

each day. Due to the complexity of the Kew Gardens Interchange, the project is split into four

construction contracts.

The contract described herein is the second contract within the interchange and is designated as Contract

2A. This contract encompasses the segment of the Northbound Van Wyck Expressway (VWE) between

Hoover Avenue and Jewel Avenue. The third planned contract, designated Contract 2B, includes the

Southbound VWE and associated ramps.

Hoover

Ave.

AVE

TRB 2014 Annual Meeting Paper revised from original submittal.

P a g e | 2

Figure 1 – Project Area

The structures within Contracts 2A & 2B project limits are:

Mainline

-NB Van Wyck Expressway Viaduct (BIN 1-05575-C)

-SB Van Wyck Expressway Viaduct (BIN 1-05575-9)

Ramps

-EB Union Turnpike/Jackie Robinson Parkway to NB Van Wyck Exp.- Ramp KB (BIN 1-05575-B)

-SB Van Wyck Expressway to WB Union Turnpike- Ramp KA (BIN 1-07609-0)

-EB Union Turnpike/Jackie Robinson merge to Ramp KB (BIN 1-07373-0)

Figure 2 – Aerial View Kew Gardens Interchange

The Van Wyck Expressway Mainline Viaducts will be replaced on a new alignment, along with two ramp

structures to the VWE. The superstructure of the merge to KB ramp will be replaced. The Mainline VWE

approaches and Grand Central Parkway (GCP) connection ramps to the VWE will be replaced. The

westbound Union Turnpike (UTP) at-grade ramp to the WB GCP will be replaced on a new alignment.

The existing NYCDOT Arterial Maintenance Yard and existing MTA Jamaica Subway Yard access road

which passes under the viaduct structures at the north abutment will be realigned. The geometric

deficiencies, operational conditions, and load capacity of the structures will be improved as part of the

project.

TRB 2014 Annual Meeting Paper revised from original submittal.

P a g e | 3

Existing and proposed structure

The subject bridge for this paper is the NB VWE viaduct. Built in 1963, the existing viaduct is supported

upon a series of steel plate girders and rolled stringers in an eighteen (18) span configuration with an

overall length of 1329 feet. It handles two lanes of NB VWE traffic over the Kew Gardens Interchange.

The extent of structural deterioration and need for improved highway geometrics require that the bridge

be fully replaced.

The proposed viaduct will be a four-span continuous steel plate girder, with span lengths of 192’, 213’,

213’ and 179’ for an overall length of approximately 800 feet. The structure profile has a vertical curve

along with horizontal compound curvature of 1974’ and 2959’ radii. The concrete substructures are pile

supported. Elastomeric bearings are used with expansion at the abutments, piers 1 and 3, with fixity

provided at pier 2. Concrete shear blocks with steel guides have been provided at the piers and abutments

for transverse seismic forces and to provide guiding of the superstructure. The proposed structure will

feature improved highway geometry and carry three lanes with shoulders.

Figure 3 – Proposed Bridge Plan & Elevation View

TRB 2014 Annual Meeting Paper revised from original submittal.

P a g e | 4

Maintenance Concerns

A main location of bridge deterioration occurs at deck joints. Joint problems lead to the introduction of

water, debris and de-icing agents to the superstructure, bearings and substructure components at these

locations, resulting in the premature deterioration of these components. The replacement costs of these

components and the joint itself vary based upon the component types, span lengths and bridge location.

The existing NB VWE handles 85,000 vehicles per day with an expected 98,000 in the future, with 10%

truck traffic. Based on experience with similar roadways, NYSDOT has had maintenance concerns on

similar structures that have used multi-cell modular joints. As such, NYSDOT requested that the

structure be analyzed to determine if a joint-less alternative was feasible.

The high traffic volume on the VWE Bridge and on the at-grade roadways crossed by the bridge makes

future repairs/replacements of these components and the joint itself a major concern. By eliminating all

joints along the deck and at the abutments, these concerns can be addressed.

Joint-less Options

Several existing joint-less options were reviewed. These included integral abutments, semi-integral

abutments and joint-less deck details. With an overall span of 800’, expansion length of 405’ and curved

structure the integral and semi-integral options were not deemed to be feasible for the NB VWE. Based

on NYSDOT criteria, the allowed maximum expansion length of 165’ and maximum curvature criteria

were exceeded. Existing NYSDOT joint-less deck details were found to be applicable to expansion

lengths in the range of up to only 200’ with structures of less curvature. Additional analysis and

development was required for the range of movements to be experienced by the NB VWE.

Finite Element Analysis

A finite element model of the superstructure was developed to analyze the structure movements through

full thermal range based on AASHTO LRFD. The model included all primary members of the curved

structure. In addition to the uniform thermal load cases, a temperature gradient of 20 degrees Fahrenheit

was applied to each fascia to determine the thermal movements generated by this non-uniform heating

distribution.

Figure 4 – Proposed Analytical Model

TRB 2014 Annual Meeting Paper revised from original submittal.

P a g e | 5

Some assumptions for the model are as listed:

Assumed base construction temp is 68 deg. F

Assumed Max. temperature is 120 deg. F as per (AASHTO LRFD 4th Edition, Table 3.12.2.1-1)

& applicable NYSDOT guidance for NYC

Assumed Min. temperature is 0 deg. F as per (AASHTO LRFD 4th Edition, Table 3.12.2.1-1) &

applicable NYSDOT guidance for NYC

Calculated Uniform Temperature Rise is 52 deg. F

Calculated Uniform Temperature Fall is -68 deg. F

Displacements are computed along and perpendicular to chord

Cross slope and longitudinal slope were considered but were not included in the model

Average coefficient of friction for the bond breaker pad material is 0.2 and for concrete to

concrete is 0.6 per ACI Code. Analysis is based on average of 0.4 friction coefficient modeled

as springs at the locations of approach slab to grade beam, wing wall and sleeper slab contact

areas

Assumed 20 deg. F temperature gradient to account for differential thermal exposure along

fascias

Longitudinal springs to represent pressure relief joint asphalt stiffness were obtained by

increasing the estimated stiffness values by 20% from the average coefficient of friction

Both lateral restraint at bearings and no lateral restraint at bearings (except fixed pier 2) were

considered to determine max limits of transverse movements at approach slab ends.

Output results

The output of the thermal modeling demonstrated the longitudinal and transverse range of thermal

movements to be experienced by the structure. The length of the structure produces mostly longitudinal

movement, as expected, while the horizontal curvature of the structure introduces transverse

displacements which need to be accounted for in the joint-less design. The gradient temperature applied,

to the fascias of the structure demonstrated additional movement experienced in the transverse direction.

Figure 5 – Schematic View Showing Location For Tabulated Displacements

TRB 2014 Annual Meeting Paper revised from original submittal.

P a g e | 6

Table 1 – Summary of Thermal Displacements

The maximum displacement range of longitudinal and transverse movements were found to be 3.75” and

1.32”, respectively. These output results were used to develop the joint-less details. The model also

provided force components generated at the joint-less details to determine the magnitude of frictional

resistance developed by the deck approach slab to grade beam support interface. The force exerted back

into the superstructure from the joint-less slab friction was found to be approximately 7% of the force

imparted into the superstructure due to the elastomeric bearing stiffness resistance during temperature

deformations.

Final details

The final configuration of the bridge eliminated all deck joints on the structure and at the abutments. A

main concern was to allow for the longitudinal and transverse thermal movements with minimal friction

between the contact points of the structure and approach supports to avoid binding and associated forces.

The final details developed are shown in Figures 6 and 7. The deck slab was continued over the backwall

and is supported upon longitudinal grade beams within the approach. This deck slab extension thus

becomes the approach slab.

Thermal Displacements With Transverse Restraints

Load Case Loc. Absolute Max Absolute Max

Long. Disp. Trans. Disp.

1 2 3 4 5 6 7 8 1+3 2+4+Max(6,8)

Disp. Disp. Disp. Disp. Disp. Disp. Disp. Disp. Disp. Disp.

Along Chord Perp. To Chord Along Chord Perp. To Chord Along Chord Perp. To Chord Along Chord Perp. To Chord Along Chord Perp. To Chord

in. in. in. in. in. in. in. in. in. in.

South Approach Slab

East Face Corner 1 1.61 0.01 -2.11 -0.02 0.21 -0.05 0.38 0.09 3.73 0.12

West Face Corner 2 1.62 0.21 -2.11 -0.28 0.34 -0.05 0.26 0.09 3.73 0.57

North Approach Slab

East Face Corner 3 1.55 0.02 -2.03 -0.02 0.20 -0.04 0.37 0.09 3.58 0.13

West Face Corner 4 1.55 0.23 -2.03 -0.30 0.33 -0.05 0.24 0.09 3.59 0.62

Thermal Displacements without Transverse Restraints

Load Case Loc. Absolute Max Absolute Max

Long. Disp. Trans. Disp.

1 2 3 4 5 6 7 8 1+3 2+4+Max(6,8)

Disp. Disp. Disp. Disp. Disp. Disp. Disp. Disp. Disp. Disp.

Along Chord Perp. To Chord Along Chord Perp. To Chord Along Chord Perp. To Chord Along Chord Perp. To Chord Along Chord Perp. To Chord

in. in. in. in. in. in. in. in. in. in.

South Approach Slab

East Face Corner 1 1.61 -0.02 -2.10 0.03 0.13 -0.84 0.46 0.87 3.71 0.92

West Face Corner 2 1.62 0.18 -2.12 -0.23 0.46 -0.85 0.14 0.87 3.75 1.28

North Approach Slab

East Face Corner 3 1.54 -0.01 -2.01 0.01 0.12 -0.81 0.45 0.85 3.55 0.87

West Face Corner 4 1.56 0.20 -2.04 -0.26 0.45 -0.82 0.12 0.86 3.60 1.32

West Face 20 Def F East Face 20 Def F

Temperature Rise Temperature Fall Day Time Temp Change Day Time Temp Change

West Face 20 Def F East Face 20 Def F

Temperature Rise Temperature Fall Day Time Temp Change Day Time Temp Change

TRB 2014 Annual Meeting Paper revised from original submittal.

P a g e | 7

Figure 6 – South Approach Slab Plan

The use of longitudinal grade beams reduces the area of contact between the approach slab and this

interface. This also allows better control on the construction tolerances of these interface points. To

reduce frictional forces between the approach slab and longitudinal grade beam supports, the grade beams

will receive a steel trowel finish and will be finished to match the profile and cross slope of the roadway.

A 2-layer synthetic bond breaker sheet will be supplied between the grade beams and approach slab to

reduce friction.

Beyond the approach slab is an asphalt pressure relief joint that can contract and expand to handle the

longitudinal movements. This pressure relief joint is supported on a sleeper slab which is also supported

upon the longitudinal grade beams within the approach.

TRB 2014 Annual Meeting Paper revised from original submittal.

P a g e | 8

Figure 7 – South Approach Slab Detail

TRB 2014 Annual Meeting Paper revised from original submittal.

P a g e | 9

The subgrade below the grade beams will utilize a select structural fill compacted to 95% standard proctor

to address settlement at the approach grade beams. Weep holes and underdrains have been provided at

the sleeper slab below the pressure relief joint to address potential water.

To further reduce frictional concerns and binding, a 1” gap between the top of backwall and deck slab

was provided to avoid friction and binding at this interface. This gap is filled with a compressible foam.

To reduce potential friction/binding under the approach slab between the sub-base and approach slab, a 6”

haunch of the slab between grade beam supports was provided.

To address transverse movements the approach slab is cast above the wingwalls, with a bond breaker

supplied, so as not to restrict transverse deformations. At the sleeper slab/wingwall location, a 2”

transverse gap with compressible filler is supplied to alleviate potential stresses between the sleeper slab

to the wingwalls if future slab movement occurs.

The deck and abutment areas at the approach slab were provided with additional reinforcement to handle

potential forces transmitted back through the joint-less system. Checks of the superstructure and

substructure were performed to ensure potential forces generated by a failure of the joint could be handled

by the structure.

Conclusion

In an effort to reduce maintenance of the proposed structure, NYSDOT will utilize the proposed details as

a pilot program to ascertain its effectiveness. Typical NYSDOT joint-less details have been limited to

shorter span, less curved bridges with expansion lengths of only up to 200’. The proposed NB VWE

bridge is curved and has an expansion length of 405’ making it the longest, curved structure to be joint-

less for NYSDOT. The elimination of joints along the bridge has the potential to reduce deterioration of

the structure. Their history with multi-cell modular joints on similar length structures with high traffic

volumes has led to this pilot test. The pressure relief joint will require maintenance every 7 years or so

but this is viewed as minor, routine maintenance which can be done quickly by a highway maintenance

crew as compared to the more extensive work needed to repair or replace a multi-cell modular joint at this

high traffic location.

The project is currently in construction with the bridge to be in service in 2014. The contractor has been

made aware that maintaining quality control during construction will be essential in order to reduce the

potential frictional issues that could arise from improper installation of the proposed details.

Thermal modeling of the curved structure revealed that transverse movements can be significant and need

to be considered in joint design. A thermal gradient on the curved structure adds to the overall transverse

movement and also requires consideration in joint design. As a test program, the tracking of the in-use

results of the joint, its durability, effectiveness and the required maintenance cycles of the pressure relief

joint will be compiled and reviewed. This information will allow NYSDOT to ascertain if implementing

more joint-less details on longer span and curved structures is feasible.

Acknowledgments:

Zhi Wen, P.E., Hardesty and Hanover, New York, NY

TRB 2014 Annual Meeting Paper revised from original submittal.