Chapter 2
Chapter 2
Chapter 2
FHWA expects specific information on scour and backwater elevations for the
permanent bridge piers, as well as, for any temporary falsework bents placed in the
waterway opening.
After the piers have been located, a memo requesting a Hydraulics Report should be sent
to the HQ Hydraulics Unit. The HQ Hydraulics Unit will submit a report for inclusion as an
appendix to the TS&L report.
The State Bridge and Structures Architect should be consulted early in the TS&L study
period. “Notes to the File” should be made documenting the aesthetic requirements and
recommendations of the State Bridge and Structures Architect.
Cost backup data is needed for any costs used in the TS&L study. FHWA expects TS&L
costs to be based on estimated quantities. This cost data is to be included in an appendix
to the TS&L report. The quantities should be compatible with the S&E Engineer’s cost
breakdown method. The Specifications & Estimates Engineers will check the designer's
estimated costs included in TS&L reports. In the case of consultant prepared TS&L
reports, the designer shall have the S&E Engineers check the construction costs.
2.1.5.B.2 Photographs
There should be enough color photographs to provide the look and feel of the bridge site.
The prints should be numbered and labeled and the location indicated on a diagram.
2.1.5.B.3 Introduction
The introduction describes the report, references, and other reports used to prepare the
TS&L study. The following reports should be listed, if used.
• Design Reports and Supplements
• Environmental Reports
• Architectural Visual Assessment or Corridor Theme Reports
• Hydraulic Report
• Geotechnical Reports
2.1.5.B.8 Drawings
Preliminary plan drawings of the recommended alternative are included in an appendix.
The drawings show the plan, elevation, and typical section. For projects where alternative
designs are specified as recommended alternatives, preliminary plan drawings for each of
the different structure types shall be included. Supplemental drawings showing special
features, such as complex piers, are often included to clearly define the project.
2.2.1.A.1 Schedule
Development of the Preliminary Plan is the first milestone in the Structure design process.
The Scope Of Work (SOW) agreement negotiated between the Region Design PEO
and the Bridge and Structures Office at or shortly after the project kickoff establishes
the deliverables (design submittals) to be produced and the due dates for the various
deliverable review milestones for the specific project.
The Structural Submittal Expectations Matrix at www.wsdot.wa.gov/publications/fulltext/
ProjectMgmt/DEM/Bridge.pdf outlines the expected content of the design submittal
deliverables at specific stages of design development.
2.2.1.B Responsibilities
In general, the responsibilities of the designer, checker, detailer, and Design Unit
Manager are described in Section 1.2.2. The Preliminary Plan designer as defined in
Section 2.2.1.A.3 is responsible for developing a Preliminary Plan for the bridge or buried
structure. The Preliminary Plan must be compatible with the geometric, aesthetic, staging,
geotechnical, hydraulic, and structural requirements and conditions at the bridge site as
presented by the Structure Site Data.
The Structural Design Unit Manager shall be kept informed of progress on the Preliminary
Plan so that the schedule can be monitored. If problems develop, the Structural Design
Unit Manager can request adjustments to the schedule or allocate additional manpower
to meet the schedule.
The Preliminary Plan designer keeps the job file up-to-date by documenting all
conversations, meetings, requests, questions, and approvals concerning the project.
Notes-to-the-designer, and details not shown in the preliminary plan shall be documented
in the job file.
The checker, as defined in Section 2-2.1.A.5, shall provide an independent review of the
plan, verifying that it is in compliance with the Structure Site Data as provided by the
Region and as corrected in the job file. The plan shall be compared against the Preliminary
Plan checklist (see Appendix 2.2-A4) to ensure that all necessary information is shown.
The checker reviews the plan for consistency with office design practice, detailing
practice, and for constructability.
The Preliminary Plan shall be detailed using current office CAD equipment and software.
2.2.1.D Coordination
The designer is responsible for coordinating the design and review process throughout
the project. This includes seeking input from various WSDOT Offices and outside
agencies. The designer should consult with State Geotechnical Office, HQ Hydraulics
Office, Bridge Preservation Office, and Region design and maintenance, and other
resources for their input..
One aspect of coordination with the Region Design PEO is review of the Not Included
In Bridge Quantities List (NIBQ), DOT Form 230-038 - see Appendix 12.1-A1. The NIBQ
itemizes elements shown in the Preliminary Plan that are not related to the structural
design, but rather are of civil design context and as such are the design responsibility
of the Region. Creation of the NIBQ helps to ensure that responsibility for all elements
identified in the Preliminary Plan is clearly assigned and understood.
2.2.2 Documentation
2.2.2.E Notes
Notes of meetings with Regions and other project stakeholders shall be included in the
job file.
2.2.3.B Safety
Feasibility of falsework (impaired clearance and sight distance, depth requirements,
see Section 2.3.10)
Density and speed of traffic
Detours or possible elimination of detours by construction staging
Sight distance
Horizontal clearance to piers
Hazards to pedestrians, bicyclists
2.2.3.C Economic
Funding classification (federal and state funds, state funds only, local developer funds)
Funding level
Bridge preliminary cost estimate
2.2.3.D Structural
Limitation on structure depth
Requirements for future widening
Foundation and groundwater conditions
Anticipated settlement
Stage construction
Falsework limitations
2.2.3.E Environmental
Site conditions (wetlands, sensitive areas, and cultural resources)
Environmental requirements
Mitigating measures
Construction access
2.2.3.F Aesthetic
General appearance
Compatibility with surroundings and adjacent structures
Visual exposure and experience for public
2.2.3.G Construction
Ease of construction
Falsework clearances and requirements
Erection problems
Hauling difficulties and access to site
Construction season
Time limit for construction
Use of ABC methods
2.2.3.H Hydraulic
Bridge deck drainage
Stream flow conditions and drift
Passage of flood debris
Scour, effect of pier as an obstruction (shape, width, skew, number of columns)
Bank and pier protection
Consideration of a culvert as an alternate solution
Permit requirements for navigation and stream work limitations
2.2.3.I Maintenance
Concrete vs. Steel
Expansion joints
Bearings
Deck protective systems
Inspection and Maintenance Access (UBIT clearances) (see Figure 2.3.11-1)
2.2.3.K Alternatives
Process of developing alternative designs as described I Section 2.2.1-E.
2.2.3.L Other
Prior commitments made to other agency officials and individuals of the community
Recommendations resulting from preliminary studies
2.2.4 Permits
2.2.4.A Coast Guard Waterway Jurisdiction and Navigation Permits for New
Construction
For all waterway crossings, the US Coast Guard shall be contacted for determination
and confirmation of waterway jurisdiction and any associated permit requirements or
categorical assignment. When the Structural Clear Span parallel to the roadway centerline
is less than or equal to 30 feet, this action is the responsibility of the Region, whether by
the Region Design Project Office or the associated Region Environmental Services Office
(ESO).
When the Structural Clear Span parallel to the roadway centerline is greater than 30 feet,
this action is the responsibility of either the Region ESO, ideally as part of the project
scoping phase, or the Bridge and Structures Office as part of the preliminary plan process.
Based on the response provided by the US Coast Guard, whether through the Region or
through the Coast Guard Liaison Engineer, the preliminary plan identifies the waterway
jurisdiction status in the left margin of the plan. The USCG block specifies whether the
USCG has jurisdiction or not, along with the date that the USCG made the determination,
and indicates whether a USCG navigation permit is required.
When the response received from the US Coast Guard indicates that a navigation permit
is required, the Bridge and Structures Office is responsible for coordinating and applying
for this permit, in accordance with Design Manual M 22.01 Section 710.03. The Coast
Guard Liaison Engineer in the Bridge Project Support Unit of the Bridge and Structures
Office is responsible for this.
See the Design Manual M 22-01, chapter covering Environmental Permits and Approvals,
or the Environmental Manual Chapter 500 for general permitting information.
Section 9 Coast Guard Permit – Information and Permitting procedures can be found
at www.dco.uscg.mil/Our-Organization/Assistant-Commandant-for-Prevention-
Policy-CG-5P/Marine-Transportation-Systems-CG-5PW/Office-of-Bridge-Programs/
Bridge-Permit-Application-Process.
The work on developing the permit application should be started early in the preliminary
plan process so that it is ready to be sent to the US Coast Guard at least eight months
prior to the project ad date. The Coast Guard Liaison Engineer should be included in
all distributions of the Preliminary Plan as outlined in Sections 2.2.1.A.5, 2.2.1.A.8, and
2.2.1.A.9. The Coast Guard Liaison Engineer uses these Preliminary Plans to develop the
Coast Guard Application plan sheets, which become part of the permit.
2.2.4.C Other
All other permits will be the responsibility of the Region (see the Design Manual M 22-01).
The Bridge and Structures Office may be asked to provide information to the Region to
assist them in making applications for these permits.
Plan, prepares, signs, and dates a cost estimate summary sheet, and returns the package
to the designer.
When the Preliminary Plan is presented to the State Bridge Design Engineer for signature
(see Section 2.2.6.B), the submittal shall include the summary sheet prepared by the
Bridge Project Support Engineer or designee. The summary sheet and backup data is then
placed in the job file. Do not send the summary sheet to the Region.
After submittal of the Preliminary Plan to the Region, the Region shall be notified
immediately of any increases in the preliminary cost estimate during the structural design.
2.2.6 Approvals
2.2.6.C Region
The Region Project Office reviews the Preliminary Plan for compliance and agreement
with the Structure Site Data. The Region Project Office answers any “Notes to the Region”
that have been listed on the plan. When this review is complete, the Regional Project
Development Engineer/Engineering Manager or equivalent position, or designee, signs
the plan. The Region sends back a print of the signed plan with any comments noted in
red (additions) and green (deletions) along with responses to the questions raised in the
“Notes to the Region.”
2.2.6.D Railroad
When a railroad is involved with a structure on a Preliminary Plan, the HQ Design Office
Railroad Liaison must be involved during the plan preparation process. A copy of the
Preliminary Plan is sent to the HQ Design Office Railroad Liaison, who then sends a copy
to the railroad involved for their review and comments.
The railroad will respond with comments to the HQ Design Office Railroad Liaison. The
comment form or email is then routed to the Project Office for coordination with the
Bridge and Structures Office for a response to the railroad. The review process continues
with the railroad until 100% plans have been accepted by the railroad as “No Exceptions
Taken”. Railroads do not approve WSDOT bridge plans, but the notation allows the
project to continue with an agreement and right of entry onto railroad property for
construction. Please consult the Union Pacific Railroad-BNSF Railway Guidelines for Railroad
Grade Separation Projects for additional requirements.
For design plans prepared within the Bridge and Structures Office, the Design Unit
Manager or lead designer will be responsible for coordinating and providing shoring plans
for structures adjacent to railroads. Shoring plans on railroad property or adjacent to
track must conform to the railroads Guidelines for Temporary Shoring (UPRR and BNSF).
It is recommended that the Construction Support Unit design, prepare, stamp, and sign
shoring plans. However, the design unit may elect to design, prepare, stamp, and sign
shoring plans.
For consultant prepared design plans, the Design Unit Manager or lead reviewer will be
responsible for coordinating and having the consultant design shoring plans for structures
adjacent to railroads. The Construction Support Unit has design criteria and sample plan
details which can be used by the design units and consultants.
A Construction Support engineer is available to attend design project kick-off meetings
if there is a need for railroad shoring plans or other constructability issues associated
with the project. Regardless of who prepares the bridge plans, all shoring plans should be
reviewed by the Construction Support Unit before they are submitted for railroad review
and approval at the Constructability Review stage.
At the Constructability Review stage or sooner if possible, especially for seismic retrofit
project, the S&E Engineer will send copies of the layout, foundation plan, temporary
shoring plans, and appropriate special provision section for structures adjacent to
railroads to the HQ Design Office Railroad Liaison, who will submit this package to the
appropriate railroad for review. The shoring plans shall show the pressure loading diagram
and calculations to expedite the railroad’s review.
2.3.1.A General
A highway crossing is defined as a grade separation between two intersecting roadways.
Naming convention varies slightly between mainline highway crossings and ramp
highway crossings, but essentially, all bridges carry one highway, road, or street over the
intersecting highway, road, or street.
Bridge piers and abutments ideally should be placed such that the minimum clearances
can be satisfied. However, if for structural or economic reasons, the best span
arrangement requires a pier to be within clear zone or recovery area, and then guardrail or
barrier can be used to mitigate the hazard.
There are instances where it may not be possible to provide the minimum horizontal
clearance even with guardrail or barrier. An example would be placement of a bridge pier
in a narrow median. The required column size may be such that it would infringe on the
shoulder of the roadway. In such cases, the barrier safety shape would be incorporated
into the shape of the column. Barrier or guardrail would need to taper into the pier at a
flare rate satisfying the criteria in the Design Manual M 22-01. See Figure 2.3.1-2. The
reduced clearance to the pier would need to be approved by the Region. Horizontal
clearances, reduced temporarily for construction, are covered in Section 2.3.9.
For the general case of bridges on wall type abutments or “closed” abutments, the
controlling factors are the required horizontal clearance and the size of the abutment.
This situation would most likely occur in an urban setting or where right of way or span
length is limited.
2.3.2.B Criteria
The initial Preliminary Plan shall be prepared in accordance with the criteria of this section
to apply uniformly to all railroads. Variance from these criteria will be negotiated with the
railroad, when necessary, after a Preliminary Plan has been provided for their review.
Figure 2.3.2-1 Determination of Bridge Length For a Highway Over Railway Grade
Separation
2.3.3.I Buried structures that qualify as a bridge per National Bridge Inspection
Standards (NBIS) shall be designed to meet above requirements for Water
Crossings.
4 x 4 joists
6″ depth for segmental falsework release
2.3.10.B Falsework Spans > 36′ or Spans with Skews or Limited Falsework Depth
While the falsework or construction openings are measured normal to the alignment
which the falsework spans, the falsework span is measured parallel to the bridge
alignment.
The Preliminary Plan designer shall perform preliminary design of the falsework
sufficiently to determine its geometric and structural feasibility. Shallow, heavy, close-
spaced wide-flange steel beams may be required to meet the span requirements
within the available depth. The preliminary design shall be based on design guides in
the Standard Specifications Section 6-02.3(17). Beams shall be designed parallel to the
longitudinal axis of the bridge. The falsework span deflection shall be limited according to
the Standard Specifications Section 6-02.3(17)B: generally span/360 for a single concrete
placement, such as a slab, and span/500 for successive concrete placement forming a
composite structure. This limits the stresses in the new structure from the construction
and concrete placement sequences. Beam sizes shall be shown in the final plans (and in
the Preliminary Plans as required) with the Contractor having the option of submitting
an alternate design. The designer shall verify availability of the beam sizes shown in
the plans.
2.3.11.A General
FHWA mandates that bridges be inspected every 24 months. The BPO inspectors are
required to access bridge components to within 3′ for visual inspection and to access
bearings close enough to measure movement. Maintenance personnel need to access
damaged members and locations that may collect debris. This is accomplished by using
many methods. Safety cables, ladders, bucket trucks, Under Bridge Inspection Truck
(UBIT), (see Figure 2.3.11-1), and under bridge travelers are just a few of the most
common methods. Preliminary Plan designers need to be aware of these requirements
and prepare designs that allow access for bridge inspectors and maintenance personnel
throughout the Preliminary Plan and TS&L planning phases.
8'-6"
2.3.11.C Travelers
Under bridge travelers, placed on rails that remain permanently on the bridge, can
be considered on large steel structures. This is an expensive option, but it should be
evaluated for large bridges with high average daily traffic (ADT) because access to the
bridge would be limited by traffic windows that specify when a lane can be closed. Some
bridges are restricted to weekend UBIT inspection for this reason.
2.4.1.A.1 Application
Used for simple and continuous spans up to 60′.
2.4.1.A.2 Characteristics
Design details and falsework relatively simple. Shortest construction time for any cast-in-
place structure. Correction for anticipated falsework settlement must be included in the
dead load camber curve because of the single concrete placement sequence.
2.4.1.B.1 Application
This type of Super Structure is not recommended for new bridges. It could only be used
for bridge widening and bridges with tight curvature or unusual geometry.
Used for continuous spans 30′ to 60′. Has been used for longer spans with inclined
leg piers.
2.4.1.B.2 Characteristics
Forming and falsework is more complicated than for a concrete slab. Construction time is
longer than for a concrete slab.
2.4.1.C.1 Application
This type of super structure is not recommended for new bridges. It could only be used
for bridge widening and bridges with tight curvature or unusual geometry.
Used for continuous spans 50′ to 120′. Maximum simple span 100′ to limit excessive
dead load deflections.
2.4.1.C.2 Characteristics
Forming and falsework is somewhat complicated. Construction time is approximately
the same as for a tee-beam. High torsional resistance makes it desirable for
curved alignments.
2. Variable Depth
Adjust ratios to account for change in relative stiffness of positive and negative
moment sections.
*If the configuration of the exterior web is sloped and curved, a larger depth/span
ratio may be necessary.
2.4.1.D.1 Application
Normally used for continuous spans longer than 120′ or simple spans longer than 100′.
Should be considered for shorter spans if a shallower structure depth is needed or for
bridges with tight horizontal curvature.
2.4.1.D.2 Characteristics
Construction time is somewhat longer due to post-tensioning operations. High torsional
resistance makes it desirable for curved alignments.
2.4.1.E.1 Application
Local precast fabricators have several standard forms available for precast concrete
sections based on the WSDOT standard girder series. These are versatile enough to cover
a wide variety of span lengths.
WSDOT standard girders are:
1. WF100G, WF95G, WF83G, WF74G, WF58G, WF50G, WF42G, WF36G, W74G,
W58G, W50G, and W42G precast, prestressed concrete I-girders requiring a cast-in-
place reinforced concrete bridge deck used for spans less than 200-feet. The number
(eg. 95) specifies the girder depth in inches.
2.4.1.E.2 Characteristics
Superstructure design is quick for pre-tensioned girders with proven user-friendly
software (PGSuper, PGSplice, and QConBridge)
Construction details and forming are fairly simple. Construction time is less than for a
cast-in-place bridge. Little or no falsework is required. Falsework over traffic is usually not
required; construction time over existing traffic is reduced.
Precast girders usually require that the bridge roadway superelevation transitions begin
and end at or near piers; location of piers should consider this. The Region may be
requested to adjust these transition points if possible.
Fully reinforced, composite 8 inch cast-in-place deck slabs continuous over interior piers
or reinforced 5 inch cast-in-place deck slabs continuous over interior piers have been
used with e. and f.
2.4.1.G.1 Use
Used for simple spans up to 260′ and for continuous spans from 120′ to 400′. Relatively
low dead load when compared to a concrete superstructure makes this bridge type an
asset in areas where foundation materials are poor.
Inside clear height of less than 5 feet shall not be used because reasonable inspection
access cannot be provided.
2.4.1.G.2 Characteristics
Construction details and forming are more difficult than for a steel plate girder. Shipping
and erecting of large sections must be reviewed. Current cost information should be
considered because of changing steel market conditions.
2.4.1.H.1 Application
Used for simple spans up to 300′ and for continuous spans up to 1,200′. Used where
vertical clearance requirements dictate a shallow superstructure and long spans or where
terrain dictates long spans and construction by cantilever method.
2.4.1.H.2 Characteristics
Construction details are numerous and can be complex. Cantilever construction method
can facilitate construction over inaccessible areas. Through trusses are discouraged
because of the resulting restricted horizontal and vertical clearances for the roadway.
2.4.1.I.1 Application
Used for continuous spans from 200′ to 700′. Used where site dictates long spans and
construction by cantilever method.
2.4.1.I.2 Characteristics
Use of travelers for the form apparatus facilitates the cantilever construction method
enabling long-span construction without falsework. Precast concrete segments may be
used. Tight geometric control is required during construction to ensure proper alignment.
2.4.1.J.1 Use
For railway over highway grade separations, most railroad companies prefer simple span
steel construction. This is to simplify repair and reconstruction in the event of derailment
or some other damage to the structure.
2.4.1.J.2 Characteristics
The heavier loads of the railroad live load require deeper and stiffer members than for
highway bridges. Through girders can be used to reduce overall structure depth if the
railroad concurs. Piers should be normal to the railroad to eliminate skew loading effects.
2.4.1.K Timber
2.4.1.K.1 Use
Generally used for spans under 40′. WSDOT restricts the use of timber girders for bridge
superstructures to non-vehicle use bridges or temporary bridges.
2.4.1.K.2 Characteristics
Excellent for short-term duration as for a detour. Simple design and details.
2.4.1.L Other
Bridge types such as cable-stayed, suspension, arch, tied arch, and floating bridges have
special and limited applications. The use of these bridge types is generally dictated by
site conditions. Preliminary design studies will generally be done when these types of
structures are considered.
2.5.2.A Wingwalls
The size and exposure of the wingwall at the end pier should balance, visually, with
the depth and type of superstructure used. For example, a prestressed girder structure
fits best visually with a 15′ wingwall (or curtain wall/retaining wall). However, there
are instances where a 20′ wingwall (or curtain wall/retaining wall) may be used with a
prestressed girder (maximizing a span in a remote area, for example or with deep girders
where they are proportionally better in appearance). The use of a 20′ wingwall shall be
approved by the Bridge Design Engineer and the State Bridge and Structures Architect.
It is less expensive for bridges of greater than 40′ of overall width to be designed with
wingwalls (or curtain wall/retaining wall) than to use a longer superstructure.
2.5.5 Superstructure
The horizontal elements of the bridge are perhaps the strongest features. The sizing
of the structure depth based on the span/depth ratios in Section 2.4.1, will generally
produce a balanced relationship.
Designs rising to the level of "Art" shall be subject to the procedures outlined in the
Design Manual M 22-01.
Haunches or rounding of girders at the piers can enhance the structure’s appearance.
The use of such features should be kept within reason considering fabrication of materials
and construction of formwork. The amount of haunch should be carefully reviewed for
overall balance from the primary viewing perspective. Haunches are not limited to cast-in-
place superstructures, but may be used in special cases on precast, prestressed I girders.
They require job-specific forms which increase cost, and standard design software is not
directly applicable.
The slab overhang dimension should approach that used for the structure depth. This
dimension should be balanced between what looks good for aesthetics and what is
possible with a reasonable slab thickness and reinforcement.
For box girders, the exterior webs can be sloped, but vertical webs are preferred. The
amount of slope should not exceed l½: l for structural reasons, and should be limited
to 4:1 if sloped webs are desired. Sloped webs should only be used in locations of high
aesthetic impact.
When using precast, prestressed girders, all spans shall be the same series, unless
approved otherwise by the Bridge Design Engineer.
2.6 Miscellaneous
2.6.1 Structure Costs
See Section 12.3 for preparing cost estimates for preliminary bridge design.
2.7.1.A General
Fractured Fin Finish shall be used on the exterior face of the traffic barrier. All other
surfaces shall be Plain Surface Finish.
Exposed faces of wingwalls, columns, and abutments shall be vertical. The exterior face
of the traffic barrier and the end of the intermediate pier crossbeam and diaphragm shall
have a 1:12 backslope.
2.7.1.B Substructure
End piers use the following details:
15-foot wingwalls with prestressed concrete girders up to 74-inches in depth or a
combination of curtain wall/retaining walls.
Stub abutment wall with vertical face. Footing elevation, pile type (if required), and
setback dimension are determined from recommendations in the State Geotechnical
Office Geotechnical Report.
Intermediate piers use the following details:
“Dropped” Crossbeams – The crossbeam below the girders is designed for the girder and
bridge deck dead load, construction loads, live load, and superimposed dead loads. The
minimum depth of the crossbeam shall be 3-feet. This crossbeam may be used for simple
span continuous prestressed concrete girder bridges and continuous steel girder bridges.
“Semi-raised” Crossbeams – The crossbeam below the girders is designed for the girder
and slab dead load, and construction loads. The crossbeam and the diaphragm together
are designed for all live loads and composite dead loads. The minimum depth of the
crossbeam shall be 3-feet.
“Raised” Crossbeams – The crossbeam is at the same level as the girders are designed for
all dead and live loads.
Round Columns – Columns shall be 3-feet to 6-feet diameter. Dimensions are constant
full height with no tapers. Bridges with roadway widths of 40-feet or less will generally be
single column piers. Bridges with roadway widths of greater the 40-feet shall have two or
more columns, following the criteria established in Section 2.3.1.H. Oval or rectangular
column may be used if required for structural performance or bridge visual.
2.7.1.C Superstructure
Concrete Slab – 7½ inch minimum thickness with epoxy coated steel reinforcing bars in
general with 5 inch minimum thickness for deck girders and 8 inch minimum thickness for
steel girders.
Prestressed Concrete Girders – Girder spacing will vary depending on roadway width
and span length. The bridge deck overhang dimension is approximately half of the girder
spacing. Girder spacing typically ranges between 6-feet and 12-feet.
Intermediate Diaphragms – Locate in accordance with Table 5.6.2-1 and Section 5.6.4.C.
Provide full or partial depth in accordance with Section 5.6.4.C.4.
End Diaphragms – “End Wall on Girder” type.
Traffic Barrier – Use 3’-6” high “F-shape” or Single-sloped barrier to meet worker fall
protection requirements.
Fixed Diaphragm at Inter. Piers – Full or partial width of crossbeam between girders and
outside of the exterior girders.
Hinged Diaphragm at Inter. Piers – Partial width of crossbeam between girders.
Sloped curtain panel full width of crossbeam outside of exterior girders, fixed to ends
of crossbeam.
BP Rail – 3′–6″ overall height for pedestrian traffic. 4′–6″ overall height for
bicycle traffic.
Sidewalk – 6-inch height at curb line. Transverse slope of -0.02 feet per foot towards the
curb line.
Sidewalk barrier – Inside face is vertical. Outside face slopes 1:12 outward.
Expansion Joints – refer to table in Section 9.1.1 for guidance regarding maximum bridge
superstructure length beyond which the use of either intermediate expansion joints or
modular expansion joints at the ends is required.
2.7.1.D Examples
Appendices 2.3-A2-1 and 2.7-A1-1 detail the standard design elements of a standard
highway bridge.
The following bridges are good examples of a standard highway bridge. However, they do
have some modifications to the standard.
SR 17 Undercrossing 395/110 Contract 3785
Mullenix Road Overcrossing 16/203E&W Contract 4143
2.8.2 Design
Design is determined on a case by case basis using two strategies. These strategies are
universally accepted best practices. The first, Crime Prevention through Environmental
Design (CPTED), is a multi-disciplinary approach to deterring criminal behavior. The
second, Context Sensitive Solutions (CSS), is also multi-disciplinary and focuses on
project development methods. Multi-disciplinary teams consist of engineers and
architects but may include law enforcement, local businesses, social service providers,
and psychologists.
1. CPTED principals are based upon the theory that the proper design and effective
use of the built environment can reduce crime, reduce the fear of crime, and
improve the quality of life. Built environment implementations of CPTED seek to
dissuade offenders from committing crimes by manipulating the built environment
in which those crimes proceed from or occur. The six main concepts are territoriality,
surveillance, access control, image/maintenance, activity support and target
hardening. Applying all of these strategies is key when preventing crime in any
neighborhood or right-of-way.
Natural surveillance and access control strategies limit the opportunity for crime.
Territorial reinforcement promotes social control through a variety of measures.
These may include enhanced aesthetics or public art. Image/maintenance and activity
support provide the community with reassurance and the ability to stop crime by
themselves. Target hardening strategies may involve fencing or concrete enclosures
or they may include all techniques to resolve crime or chronic trespass into one
final step.
2. WSDOT implements FHWA’s CSS design development principles. The CSS methods
require designers to consider the physical, economic, and social setting of a project.
Stakeholder’s interests are to be accounted for; including area residents and
business owners.
Figure 2.8.3-1
Page 2-50
½" GAP (TYP. AT
VERTICAL ELEMENTS)
1" GAP (TYP. AT
GALV. STEEL WELDED HORIZONTAL ELEMENTS)
WIRE MESH FABRIC
BRIDGE SECURITY FENCE
ON TOP OF ABUTMENT
PRY RESISTANT ELEMENT WITH
DIRECT CONNECTION TO RAIL
POST (TYP.)
GALV. STEEL WELDED
WIRE MESH FABRIC SEE DETAIL 1
RAIL (TYP.)
ABUTMENT FOUNDTAION
September 2023
WSDOT Bridge Design Manual M 23-50.22
Preliminary Design
Preliminary Design Chapter 2
2.10 Appendices
Appendix 2.2-A1 Bridge Site Data General
Appendix 2.2-A2 Structure Site Data Rehabilitation
Appendix 2.2-A3 Structure Site Data Stream Crossings
Appendix 2.2-A4 Preliminary Plan Checklist
Appendix 2.2-A5 Request For Geotechnical & Hydraulic Information for Bridge
Preliminary PlanRequest For Geotechnical & Hydraulic Information
for Bridge Preliminary Plan
......
: , : Washington State
Structure Site Data
•/I Department of Transportation General
Region Made By Date
I I
Structure Information
SR Structure Name Control Section Project No.
I I I
Highway Section Section, Township & Range Datum
I I
Roadway width between curbs What are expected foundation conditions?
Are overlays planned for a contract subsequent to this contra Are there security issues, such as the presence of illegal campers, that
□ Yes □ No □ N/A require design considerations?
......
:7:
Structure Site Data Rehabilitation
Washington State
/1
'l///f Department of Transportation
Region Made By Date
I I
Structure Information
SR Structure Name Control Section Project No.
I
Highway Section Section, Township & Range
I I
Vertical Datum
I I
Existing roadway width, curb to curb Left of CL Right of CL
Existing wearing surface (concrete, HMA, HMA w /membrane, MC, epoxy, other) Thickness
Attachments
□ Video tape of project
Attachments
□ Site Contour Map (See Sect. 710.04 WSDOT Design Manual)
□ Streambed: Profile and Cross Sections defining bankfull width and bank shelf widths and slopes (See Sect. 710.03
WSDOT Design Manual)
□ Photographs
□ Other Data Relative to Selection of Type and Design of Structure, Including your Recommendations (e.g., requirements
of riprap, permission of piers in channel.)
Plan Miscellaneous
Typical Section
Left Margin
Job Number
Bridge (before/with/after) Approach Fills
Structure Depth/Prestressed Girder Type
Deck Protective System
Coast Guard Permit Status
(Requirement for all water crossing)
Railroad Agreement Status
Points of Minimum Vertical Clearance
Cast-in-Place Concrete Strength
Right Margin
Control Section
Project Number
Region
Highway Section
SR Number
Structure Name
Page 2-58
Request For Geotechnical & Hydraulics Information For Bridge Preliminary Plans
Chapter 2
September 2023
WSDOT Bridge Design Manual M 23-50.22
Preliminary Design
2.99 References
1. Federal Highway Administration (FHWA) publication Federal Aid Highway
Program Manual
FHWA Order 5520.1 (dated December 24, 1990) contains the criteria pertaining
to Type, Size, and Location studies.
Volume 6, Chapter 6, Section 2, Subsection 1, Attachment 1 (Transmittal 425)
contains the criteria pertaining to railroad undercrossings and overcrossings.
2. WAC480-60 Railroad Companies - Clearances
3. American Railway Engineering and Maintenance Association (AREMA) Manual
for Railroad Engineering
Note: This manual is used as the basic design and geometric criteria by all railroads.
Use these criteria unless superseded by FHWA or WSDOT criteria.
4. WSDOT Design Manual M 22-01
5. WSDOT Geotechnical Design Manual M 46-03
6. WSDOT Hydraulics Manual M 23-03
7. WSDOT Local Agency Guidelines M 36-63
8. American Association of State Highway and Transportation Officials AASHTO LRFD
Bridge Design Specification
9. Union Pacific Railroad-BNSF Railway Guidelines for Railroad Grade Separation Projects
10. WSDOT Context Sensitive Solutions Executive Order E 1028
11. Newman, O. Defensible Space: Crime Prevention Through Urban Design. New York:
Macmillan. 1972
12. Jacobs, Jane. The Death and Life of Great American Cities. New York: Random
House. 1961