JOINTS TABLE OF CONTENTS CHAPTER 14

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1 TABLE OF CONTENTS CHAPTER 14 FILE NO. TITLE DATE TABLE OF CONTENTS, INTRODUCTION 14.TOC-1 Table of Contents Chapter May Introduction Chapter May2018 GENERAL INFORMATION Design Requirements... 03May Design Requirements and Longitudinal Deck Expansion Joints... 03May Joint Selection Criteria... 03May2018 ADHESIVE BASED JOINT SEALERS General Information... 03May Class I Adhesive Based Joint Sealers... 03May Class II Adhesive Based Joint Sealers... 03May Class III Adhesive Based Joint Sealers... 03May2018 ELASTOMERIC EXPANSION DAMS General Information... 03May General Information... 03May Design Example... 03May2018 TOOTH EXPANSION General Information... 03May Design Example... 03May Design Example... 03May Design Example... 03May Design Example... 03May Design Example... 03May Design Example... 03May2018 ASPHALT PLUG General Information... 03May2018 FLEXIBLE CONCRETE PLUG General Information... 03May2018 TABLE OF CONTENTS CHAPTER 14 SHEET 1 of 1 FILE NO. 14.TOC-1

2 INTRODUCTION The purpose of this chapter is to establish the practices and specific requirements of the Structure and Bridge Division for the design and detailing of bridge deck expansion joints, hereafter referred to as expansion joints. It also provides design aids and references to other parts of this manual to assist in the design and preparation of plans. References to the AASHTO LRFD Specifications in this chapter refer to the AASHTO LRFD Bridge Design Specifications, 7 th Edition, 2014, including the current VDOT Modifications (IIM- S&B-80). The practices and specific requirements contained in this chapter have been established based on the Structure and Bridge Division s experience, industry standards and recommendations, and technological advancements made over the years. The practices and requirements set forth herein are intended to supplement or clarify the requirements of the AASHTO LRFD Specifications, and to provide additional information to assist the designer. In the event of conflict(s) between the practices and requirements set forth herein and those contained in the AASHTO LRFD Specifications, the more stringent requirements shall govern. Standards for joints, BDEJ series, are located in Part 3 of this manual. It is expected that the users of this chapter will adhere to the practices and requirements stated herein. The current chapter will be void and replaced as written herein. NOTE: Due to various restrictions on placing files in this manual onto the internet, portions of the drawings shown do not necessarily reflect the correct line weights, line types, fonts, arrowheads, etc. Wherever discrepancies occur, the written text shall take precedence over any of the drawn view. INTRODUCTION - CHAPTER 14 SHEET 1 of 1 FILE NO

3 GENERAL INFORMATION Expansion joints shall not be placed on new bridge decks without a design waiver approved by the State Structure and Bridge Engineer (see Chapters 15 and 17). In the event that expansion joint(s) are approved for use on a new bridge structure, they must meet the following requirements: Size joints to meet the thermal, live load movement and shrinkage requirements (translation and rotation) in accordance with the current AASHTO LRFD Bridge Design Specifications. Joints shall be either the Tooth Expansion Joint ( finger joint ) or Elastomeric Expansion Dam. Class I Adhesive Based Joint Sealer can be used for approach slab to sleeper pad applications. Class II and III Adhesive Based Joint Sealers can be used under nonvehicular traffic applications. Design Requirements: The design thermal movement range associated with a uniform temperature change shall be calculated using Procedure A Temperature Ranges, AASHTO LRFD Table The moderate climate range shall be used for steel or aluminum superstructures and cold climate range shall be used for concrete superstructures. The full design thermal movement range associated with a uniform temperature change shall be used for joint design. Shrinkage shall also be considered for joint design of concrete superstructures using a shrinkage coefficient of except for segmentally constructed bridges which shall be estimated in accordance with Article For typical multi-beam/girder prestressed concrete superstructures not integral with the substructure, the shrinkage coefficient can be considered to include superstructure creep effects. All joints shall be sized and designed for the corresponding movement [deformation] with shrinkage and girder end rotation where applicable in the service limit state: LF TU x ( T) + LF SH x (shrinkage) + LF LL x (rotation) = 1.2 x (α x T R x L exp ) x (L exp x ) x (D R x sin Θ) where: LF TU = Load Factor from Table for TU deformation = 1.2 LF SH = Load Factor from Table for shrinkage = 1.0 LF LL = Load Factor from Table for LL+IM = 1.0 T = α x TR x L exp = the design thermal movement range, in. α = coefficient of thermal expansion, in./in./ F T R = temperature range, F L exp = expansion length, in. D R = rotation depth measured from top of deck slab to center of rotation at bearing Θ = design girder rotation at bearing due to live load plus impact GENERAL INFORMATION DESIGN REQUIREMENTS SHEET 1 of 3 FILE NO

4 Structure Type Coefficient of thermal expansion Steel Concrete (Reinforced & Prestressed) Joint openings shall be adjusted by t for each 10º F variation from 60º F: Total expansion length at joint (feet) Temperature variation per 10º F (t) / / / / /32 The maximum roadway surface gap in a transverse deck joint, measured in the direction of travel, shall be limited to 4 inches. The opening of tooth expansion joints may be larger than 4. Longitudinal Deck Expansion Joints: Longitudinal deck expansion joints should be avoided for bridge widths under 100. To accommodate differential lateral movement, elastomeric bearings or combination bearings with the capacity for lateral movement should be used instead of longitudinal joints where practical. For widths in excess of 100, a longitudinal deck expansion joint is recommended. Where required, place longitudinal deck expansion joints at crowns or behind barriers or curbs where possible. Elastomeric expansion dams should be used for the longitudinal deck expansion joint under vehicular applications. Use of longitudinal deck expansion joint shall be approved by the District Structure and Bridge Engineer. GENERAL INFORMATION DESIGN REQUIREMENTS AND LONG. EXP. SHEET 2 of 3 FILE NO

5 JOINT SELECTION CRITERIA Movement Rating (MR): Total movement due to thermal expansion and contraction, and live load. Joint Type Class I Adhesive Based Joint Sealers Class II Adhesive Based Joint Sealers Class III Adhesive Based Joint Sealers Elastomeric Expansion Dams Tooth Expansion Joints Asphalt Plug Joints Flexible Concrete Plug Joints Silicone Joint Seals Design Movement Range (inches) 2.0* New Bridge Approach slab to sleeper pad Not under vehicular traffic Not under vehicular traffic 4.0 Virginia Abutment and VA Pier Cap Virginia Abutment and VA Pier Cap Applications Existing Bridge See Chapter 32 See Chapter 32 See Chapter 32 See Chapter 32 See Chapter N/A See Chapter N/A See Chapter N/A See Chapter 32 Limitations / Recommendations Skews < 65 MR < 1½ Minimum install surface temperature = 40 F Skews < 45 MR < 1½ Minimum install surface temperature = 40 F Skews < 45 MR < 1½ Minimum install surface temperature = 40 F Skews < 55 Skews > 55 ; consult manufacturer Tooth plate thickness shall not exceed 3 Skews < 30 Span lengths < 100 MR < 1½ MR < 1 * Larger value can be used between approach slab and sleeper pad. Compression seals and modular joints are not permitted for use in expansion joint systems except for partial in-kind replacement in the existing bridges. Asphalt Plug Joints and Flexible Concrete Plug Joints shall only be used for bridge maintenance. GENERAL INFORMATION JOINT SELECTION CRITERIA SHEET 3 of 3 FILE NO

6 GENERAL INFORMATION FOR ADHESIVE BASED JOINT SEALERS: This section discusses the use of three different adhesive-based joint sealers: Class I, Class II, and Class III. The designer shall refer to Part 3 of this manual for Standards and Notes to Designer pertaining to each class of adhesive based joint sealers. Adhesive based joint sealers are used in bridge applications for new construction, rehabilitation, maintenance and joint reconstruction. Adhesive based joint sealers are generally used to accommodate smaller joint movements, typically less than 2 ; however, Class II joint seals can accommodate larger movements if needed. Adhesive based joint sealers shall not be used if the joint s anticipated movement will exceed the system s allowable movement range. It is very important that the designer selects the proper seal size, since the waterproofing capabilities are dependent on the internal forces generated while the sealer is in compression. When skews exceed 30 degrees, reducing the allowable movement range shall be considered to reduce the stresses caused by racking. In addition to racking stresses, joint skews between 25 degrees and 35 degrees are more susceptible to snowplow damage due to the angle of the blade. As a result, it is recommended that all adhesivebased joint sealers be recessed a minimum of 3/8 below the roadway surface when installed to minimize snowplow or other vehicular impact to the sealer material.. ADHESIVE BASED JOINT SEALERS GENERAL INFORMATION SHEET 1 of 4 FILE NO

7 CLASS I JOINT SEALERS: Class I joint sealers consist of an extruded polychloroprene (neoprene) material, which is air pressurized and bonded in place with a structural epoxy adhesive. A typical sealer cross section is shown below. Class I joint sealers are recommended for bridge applications requiring straight, skewed, or curved joint systems. Class I joint sealers can accommodate new joint construction for approach slab to sleeper pad configurations. Class I joint sealers can provide up to +/- 50% movement, allow for multi-directional movement, and shall be installed at the nominal seal widths provided below. The following table reflects the typical seal widths to be used for the associated joint openings: Nominal Seal Installation Dimensions Joint Width (b) Depth Below Deck / Slab (h + 3/8 ) Joint Opening (w) Movement Range Min. Max. Total Movement Note: Shaded rows reflect seal sizes that should only be used between approach slab and sleeper pad for new bridge construction. Class I joint sealers allow up to 50% of the total movement range normal to the joint for racking. ADHESIVE BASED JOINT SEALERS CLASS I JOINT SEALERS SHEET 2 of 4 FILE NO

8 CLASS II JOINT SEALERS: Class II joint sealers consist of an inverted V shaped, preformed, extruded silicone rubber or EPDM seal, with a structural adhesive. A typical sealer cross section is shown below. Class II joint sealers are utilized for new joint construction under non-vehicular traffic or existing bridge maintenance applications. For more information, refer to Chapter 32. Class II joint sealers shall be installed at the minimum seal widths provided below. The following table reflects the typical seal widths to be used for the associated joint openings: Nominal Seal Installation Dimensions Width (b) Depth Below Deck (h + 3/8 ) Joint Opening (w) Movement Range Min. Max. Total Movement Class II joint sealers allow up to 20% of the total movement range normal to the joint for racking. ADHESIVE BASED JOINT SEALERS CLASS II JOINT SEALERS SHEET 3 of 4 FILE NO

9 CLASS III JOINT SEALERS: Class III joint sealers consist of a preformed, pre-compressed, self-expanding joint seal with silicone pre-coated surface bonded in place with a structural epoxy adhesive. A typical sealer cross section is shown below. Class III joint sealers are utilized for new joint construction under non-vehicular traffic or existing bridge maintenance applications. For more information, refer to Chapter 32. Class III joint sealers can provide up to +/- 50% movement and accommodate variations in joint size, and shall be installed at the nominal seal widths noted below. The following table reflects the typical seal widths to be used for the associated joint openings: Nominal Seal Installation Dimensions Width (b) Depth Below Deck (h + 3/8 ) Joint Opening (w) Movement Range Min. Max. Total Movement Class III joint sealers allow up to 40% of the total movement range normal to the joint for racking. ADHESIVE BASED JOINT SEALERS CLASS III JOINT SEALERS SHEET 4 of 4 FILE NO

10 GENERAL INFORMATION FOR ELASTOMERIC EXPANSION DAMS: Elastomeric expansion dam joint systems consist of an elastomeric gland mechanically locked between two steel edge members (typically rolled shapes) providing a watertight seal. A typical elastomeric expansion dam cross section is shown below. Elastomeric expansion dams can accommodate new joint construction for Virginia Abutments and Virginia Pier Caps or repair and maintenance of existing expansion joint systems. Elastomeric expansion dams are used to accommodate intermediate joint movement ranges, typically 2 to 4. Consideration shall be given to the racking movement on the neoprene gland as the skew of the structure increases. For skew angles > 30 degrees, but 45 degrees; racking displacement shall be 60 percent of the seal s rated capacity, or select the next larger size neoprene gland to reduce the stresses caused by racking. For skew angles > 45 degrees; racking displacement shall be 50 percent of the seal s rated capacity. When skews exceed 55 degrees, the designer shall consult the manufacturer for recommended installation requirements. Horizontal angle changes in the expansion joint greater than 35 degrees should be avoided when possible, otherwise shop vulcanization is required. ELASTOMERIC EXPANSION DAMS GENERAL INFORMATION SHEET 1 of 3 FILE NO

11 Seals should not be used if the joint s anticipated movement will exceed the system s movement range. The seals shall be placed in one continuous piece. Since the seal must be installed after the armor or steel rail is set in concrete, a minimum installation opening must be provided. The following table reflects the typical seal widths on market to be used for the associated joint openings: Seal Type Nominal Seal Width Recommended Minimum Seal Installation Width (A) Joint Opening (A) Movement Range Min. Max. Total Type Type Type Type The designer shall refer to Part 3 of this manual for Standards and Notes to Designer pertaining to Elastomeric Expansion Dams. ELASTOMERIC EXPANSION DAMS GENERAL INFORMATION SHEET 2 of 3 FILE NO

12 DESIGN EXAMPLE: A prestressed concrete girder structure has an expansion length of 300 feet with a 33-degree skew angle (measured from the centerline of the structure). Criteria: LF TU = Load Factor from Table for TU deformation = 1.2 LF SH = Load Factor from Table for shrinkage = 1.0 LF LL = Load Factor from Table for LL+IM = 1.0 T R = 80 (Cold climate range per AASHTO Table ) α = (in./in./ F) Shrinkage coefficient = D R = 88 inches (based on PCBT-77) Θ = 0.23 degrees (computed) A = total joint movement along CL bridge/structure A normal = movement normal to joint A parallel = movement parallel to joint Compute total movement, A max : A max = LF TU x ( T) + LF SH x (shrinkage) + LF LL x (rotation) = 1.2 x (α x T R x L exp ) x (L exp x ) x (D R x sin Θ) = 1.2 x ( x 80 x 300 x 12 / ) x (300 x 12 / x x (88 ) x sin(0.23 ) = = 3.5 Therefore, a 3½ joint seal is needed. Select Type 2 in the Table in File No Check racking due to skew angle: A normal = A x (cosθ) = 3.73 x cos(33 ) = 3.12 A parallel = A x (sinθ) = 3.73 x sin(33 ) = 2.03 Parallel racking / total joint movement range = 2.03 / 4.0 = 51% < 60% (for 30 o < skew 45 o ). So 4-inch seal, Type2, is OK. ELASTOMERIC EXPANSION DAMS DESIGN EXAMPLE SHEET 3 of 3 FILE NO

13 GENERAL INFORMATION FOR TOOTH EXPANSION : Tooth expansion joint systems consist of a pair of loosely interlocking steel plates that cantilever the joint opening. The cantilevered portion of each plate is made up of rows of tooth-shaped protrusions that fit into the rows of grooves in the opposing plate. The tooth plates are anchored into the deck slab or backwall of the abutment. Generally, the water and debris pass through the tooth joint opening and are taken away by a trough system. Tooth expansion joints are normally used for new joint construction with Virginia Abutments or Virginia Pier Caps. Tooth expansion joints are used to accommodate medium and larger movement ranges, typically greater than 4. Bridge decks that require greater than 10 inches of movement require design approval from the District Structure and Bridge Engineer. The steel teeth are designed to support live loads in accordance with AASHTO LRFD 3.6. At the Strength I Limit State, a load factor of 1.75, as well as an impact factor of 1.75, shall be applied to the tooth load. The capacity of the cantilever steel tooth shall be checked against the ultimate load. Tooth thickness shall not exceed 3 inches. When pedestrian or bicycle facilities are used on a bridge, the portion of the tooth expansion joints in the bike path or shoulder area should be covered with special floor plates. Additionally, tooth joint surface openings should be limited to permit safe operation of motorcycles. When the maximum longitudinal openings in the direction of traffic exceed 8 inches, the transverse opening shall not exceed 2 inches. For the maximum longitudinal openings are 8 inches or less, the transverse opening may be increased to 3 inches. The designer shall refer to Part 3 of this manual for Standards and Notes to Designer pertaining to Tooth Expansion Joints. TOOTH EXPANSION DESIGN EXAMPLE SHEET 1 of 7 FILE NO

14 DESIGN EXAMPLE: The Tooth Expansion Joint may be designed using the following values and formulas: Criteria and Assumptions: TOOTH EXPANSION DESIGN EXAMPLE SHEET 2 of 7 FILE NO

15 DESIGN EXAMPLE (CONT D) α = in/in/ F α = in/in/ F T = 120 F T = 80 F A min = 1 B min = 1.5 TL min = TL Coefficient of thermal expansion for steel beams/girders Coefficient of thermal expansion for concrete beams Temperature range for steel beams/girders Temperature range for concrete beams Minimum tooth opening Minimum tooth lap Minimum tooth length LRFD Uniform Temperature Load Factor Total thermal movement distance Tooth length CLR CLR min ϕ = skew angle Clear distance between end plates Minimum clear distance between end plates 9 abutment; 7 for pier 3 1 cos 60, 40,, C C min = 1½ 0.2, 1/8" 2" 3/16" for 2 3" 1/4" 3" Tooth opening at 60 F for steel beams/girders Tooth opening at 60 F for concrete beams Tooth lap Thickness of tooth Minimum thickness of tooth Bevel length of tooth Bevel depth of tooth F Length of 3/8 fillet weld (Category E) TOOTH EXPANSION DESIGN EXAMPLE SHEET 3 of 7 FILE NO

16 DESIGN EXAMPLE (CONT D) A two span steel plate girder bridge as shown below Total thermal movement distance Bridge skew Yield strength of tooth plate LRFD Live Load Factor LRFD Impact Factor LRFD Flexural Resistance Factor Tooth spacing Width of tooth Joint location, 0 for abutment; 1 for pier Fillet weld size 0.80 Resistance Factor of weld, AASHTO LRFD L w L wmin = 6 Weld strength Length of weld Minimum length of weld TOOTH EXPANSION DESIGN EXAMPLE SHEET 4 of 7 FILE NO

17 DESIGN EXAMPLE (CONT D) Determine Tooth Length (TL): The tooth length needs to satisfy the minimums of tooth opening, tooth lap, clear distance between end plates and thermal expansion movement. The clear distance between end plates (CLR), determined using the solved value for TL. If the minimum criterion for CLR is not achieved, then TL will be increased at increments of 1/8 until all minimums are satisfied. Calculate Initial TL: 5.31 Check minimum CLR: Since 0 (0 for abutment) 9 Check TL required to meet 1 7 TL required to satisfy all minimum requirements: max 5,, 7 Tooth Length will be rounded to up to the nearest 1/8. Clear distance between end plates: 3 1 cos Calculate Tooth Thickness (C): Tooth Thickness (C) is determined from the steel flexural capacity required to resist a 16 kip truck wheel load distributed over 20 width (AASHTO ) placed 3 from the free end of a tooth. Loading scenario assumes there is differential settlement on either side of the joint resulting in one side being higher than the other with the full wheel load to be evenly distributed over N individual teeth. Due to the round area at the base of teeth, flexural capacity is checked at a location 1 from the base of tooth. Number of teeth carrying truck wheel load: 20" 5 Load per tooth: 9.8 TOOTH EXPANSION DESIGN EXAMPLE SHEET 5 of 7 FILE NO

18 DESIGN EXAMPLE (CONT D): Moment per tooth: 1" 3" 2.45 Nominal Moment Capacity: Where, Section Modulus Check Strength I: Use 1¾ plate. Calculate remaining tooth variables: Tooth opening at 60 F: Tooth lap at 60 F: /8" 2" 3/16"for 2 3" 1/4" 3" Since D = 1.4, E = 1/8 TOOTH EXPANSION DESIGN EXAMPLE SHEET 6 of 7 FILE NO

19 DESIGN EXAMPLE (CONT D): Calculate length of weld (F): Use sufficient length of fillet weld (Category E) to resist vertical wheel load and horizontal traction load with anchors at 12 spacing. Resistance of weld: 0.6 R r = kip/in Wheel load: 16 LL = 49kip Since the wheel load is distributed over 20 width and the spacing of the anchors is 12, the wheel load is carried by each anchor or weld is " " P l = 29.4kip 3" 1.5" L w = 7.4in > L wmin = 6 So, 1.5" 9 TOOTH EXPANSION DESIGN EXAMPLE SHEET 7 of 7 FILE NO

20 GENERAL INFORMATION FOR ASPHALT PLUG : Asphalt plug joints are designed to accommodate minimal structure movements while providing a smooth transition over a joint. The system combines the use of a traffic bearing plate with special aggregate reinforced modified elastomeric material. Asphalt plug joints are only to be used for existing bridge maintenance applications. A typical joint cross section is shown below. Asphalt plug joints should not be used in applications where the adjacent pavement is subjected to significant acceleration or deceleration, such as exit ramps, as this type of loading increases the chances of the polymer modified asphalt binder to creep out of the blockout. The designer shall refer to Part 3 of this manual for Standards and Notes to Designer pertaining to Asphalt Plug Joints. ASPHALT PLUG GENERAL INFORMATION SHEET 1 of 1 FILE NO

21 GENERAL INFORMATION FOR FLEXIBLE CONCRETE PLUG : Flexible concrete plug joints are designed to accommodate minimal structure movements while providing a smooth transition over a joint. Flexible concrete plug joints are only to be used for existing bridge maintenance applications. A typical joint cross section is shown below. The designer shall refer to Part 3 of this manual for Standards and Notes to Designer pertaining to Flexible Concrete Plug Joints. FLEXIBLE CONCRETE PLUG GENERAL INFORMATION SHEET 1 of 1 FILE NO