102 - Bridge Design Submission Requirements
102.1 Plan Presentation
102.1.1 Drafting Standards
Standard line widths, lettering sizes, fonts, and symbols have been established to promote uniformity in the preparation of bridge design plans. Refer to the CADD Standards Manual (Wiki Format) for Department drafting standards. Example plans are located on the DRC – Example Plans Tab and demonstrate proper application of the Department’s drafting standards and plan presentation.
Drawings must be concise and without repetitious notes, dimensions, and details. Plans, sections, elevations, and details must be drawn accurately to scale. Scales must be large enough to show clearly all dimensions and details necessary for construction of the structure. Preferably, plans, sections and elevations should be drawn to a scale not less than ¼"= 1'-0" and details to a scale not less than 3/8"= 1'-0".
A north arrow symbol should be placed on all plan views.
When describing directions or locations of various elements of a highway project, the construction baseline and stationing should be used as a basis for these directions and locations. Elements are located either left or right of the construction baseline and near and far with respect to station progression (e.g., near abutment, left side, right railing, left far corner).
Elevation views of piers and the far abutment should be shown looking forward along the stationing of the project. The near abutment should be viewed in the reverse direction. Near and far abutments should be detailed on separate plan sheets for staged construction projects or for other geometric conditions that produce asymmetry between abutments.
For each substructure unit, the skew angle should be shown with respect to the construction baseline or, for curved structures, to a reference chord. See Section 103 – Bridge Geometry and Structure Type Selection for the definition of bridge skew.
In placing dimensions on the drawings, sufficient overall dimensions must be provided so it is not necessary for a person reading the drawings to add up dimensions in order to determine the length, width, or height of an abutment, pier, or other element of a structure.
In general, the designer should avoid showing a detail or dimension in more than one place on the plans. Duplication is usually unnecessary and always increases the risk of errors, particularly when revisions are made.
If a view or a section must be placed on another sheet, both sheets should be clearly cross-referenced.
When misinterpretation is possible, the limits of pay items must be clearly indicated on the corresponding details of a structure.
Abbreviation of words should generally be avoided. Abbreviations, unless they are common use, may cause uncertainty in interpreting the drawings. If abbreviations are used, they should be defined on the notes sheet.
102.1.2 Plan Sheet Sequence
Bridge project plans shall be assembled in the following order:
- Title sheet
- Index of sheets
- Addenda and revisions sheet
- Legend sheet
- Notes sheet
- Roadway detail and geometry sheets
- Construction details
- Bridge sheets
- Environmental compliance sheets
- Erosion control plan sheets
- Traffic control plan sheets
- Traffic sheets
- Utility sheets (if applicable)
- Right-of-way sheets (if applicable)
- Quantity sheets (as required)
Quantity sheets must provide a separate quantity summary for each bridge as well as a total project quantity summary. Quantity sheets are used when a bridge or bridges are incorporated into a project development project or when multiple bridges are included in one bridge project. When bridges are part of a project development project, a separate quantity summary for each bridge is required.
Bridge sheets are assembled in the order of construction as follows:
- Bridge notes, including bridge quantities and index of bridge sheets
- Bridge plan, section, and elevation (including key plan where applicable)
- Lay-out plan
- Foundation layout
- Pile details
- Abutment details
- Pier details
- Bearing details
- Framing details
- Beam details
- Diaphragm details
- Camber details
- Moment and shear diagrams (required for complex bridges or as directed by the Bridge Design Engineer)
- Deck and bridge railing details
- Finished deck elevations
- Expansion joint details
- Approach slab details
- Miscellaneous details
- Reinforcing bar list
- Soil borings
It is preferred that sheets be combined on smaller projects to reduce the number of sheets.
102.1.3 Bridge Sheet Preparation
In preparing bridge plans, the designer should fully implement the plan development checklists, which are available on the DRC – Bridges and Structures Tab and Project Management Tab. Bridge sheets should generally be arranged in the order the bridge will be constructed.
The number of bridge sheets will vary with the size and complexity of the structure. At a minimum, the bridge sheets must show:
- A general plan view and elevation view
- Typical bridge sections
- Substructure details
- Superstructure details
- Bearing details
- Railing and parapet details
- Reinforcement and reinforcement schedules
- Soil borings
A separate sheet is typically used for each abutment and pier. Where piles are used, a pile layout should be provided for each substructure unit.
In addition, as appropriate, the bridge sheets should show the following:
- Deck details including grades
- Joint details
- Camber diagrams
- Deck placement sequence
- One feasible bridge erection scheme (as applicable for major and/or complex structures)
- Other details necessary for constructing the bridge
General instructions for completing specific bridge sheets are presented below.
188.8.131.52 General and Project Notes
General notes include items that are applicable to all projects. Standard general notes and legend sheets are available on the DRC – CADD Tab. The most recent versions of these sheets shall be used on all projects. General notes include such items as:
- Design specifications
- Standard construction specifications
- Other notes not addressed by the Standard Specifications
Project notes include items that are specific or unique to the project. Bridge project notes include:
- Index of bridge sheets, including sheet titles and numbers
- Design criteria
- Design loading (e.g., special dead loads specific to the bridge, metal deck form dead loads, future wearing surface dead loads)
- Live load distribution method
- Vertical and horizontal datum
- Hydraulic and scour data (including information as noted in Section 104 –Hydrology and Hydraulics) for structures draining an area of ½ square miles or greater
- Structural steel specification and grade
- Welding specification and information
- Painting and protective coatings specification and direction
- Portland cement concrete class and/or strength
- Reinforcing steel specification and grade
- Prestressing steel specification and grade
- Foundation information
- Removal items
- Traffic control references
- Other specific project-related notes
184.108.40.206 Bridge Plan and Elevation
The bridge plan and elevation sheet generally serve as a record document, which contains critical information regarding the structure and project site and is referenced throughout the life of the structure. The following essential information shall be shown on the bridge plan and elevation sheet. If all of the following items cannot be accommodated on the bridge plan and elevation sheet, they may be shown on the next or succeeding sheets with proper reference.
- Plan: Outlines of substructure above ground and superstructure; length of spans along profile grade of roadway, skew angle(s), stations, and grade elevations at intersections of profile grade with centerline bearing at abutment and centerline piers; designation of piers, abutments, and wingwalls (e.g., Pier 5, Near Abutment, Wingwall A); horizontal distance between profile grade lines in the case of dual structures; contours for existing and final ground lines; location of points of minimum actual and required vertical clearances, scuppers, and lighting poles; minimum actual and required horizontal clearances between underpassing highways or centerline of railroad tracks and faces of adjacent parts of substructure; and normal horizontal clearances between faces of substructure for drainage structures.
- Elevation: Rate and direction of roadway grade, spacing of railing posts, spacing and mounting heights of lighting poles, protective fence location, finished ground line and approximate original ground line along centerline of bridge, Ordinary High Water (OHW) and design storm elevation, bottom of footing elevations, estimated pile tip elevations, and required and provided minimum vertical clearances together with the elevations that define the clearances provided. The type of joint and movement classification for each joint must be shown on the plans. The fixity at each substructure unit must be shown. For definition and requirements for highway vertical clearance, see Section 103 – Bridge Geometry and Structure Type Selection. For drainage structures, the minimum vertical clearance is the maximum unobstructed design flow depth under a bridge.
- Typical Normal Section(s) of Superstructure: Roadway width between curbs or sidewalks, overall dimensions, out-to-out faces of barriers, shoulder width, cross slopes of roadway, minimum slab thickness, girder spacing, girder type, girder size, and overhang. All applicable cross sections shall be shown on the bridge plan and elevation sheet.
- Grade Data: Horizontal and vertical alignment data, superelevation, run-in/run-out data, and points of rotation in accordance with the Road Design Manual.
220.127.116.11 Lay-Out Plan
A lay-out plan is essential to correctly convey the geometry of the bridge. The lay-out plan shall be prepared in accordance with the following direction.
- A lay-out sketch shall be shown, preferably on the first or second sheet of the structure drawings. There should be ample open space outside of the sketch to allow wing and barrier line extensions for lay-out point recordings. Frequently, exaggerations of curvature, angle, or other are necessary to show the information clearly.
- The sketch shall be as simple as possible, but as complete as possible so that the structures will be constructed according to the plans.
- All necessary tie-in dimensions between highway alignment, working points, lines of structure, and other control points shall be shown in feet to two decimal places on the sketch.
- A table of coordinates for all working points, a table of coordinates for the baseline, and coordinates to four decimal points must be provided. The following note should be included: Four place coordinates are for computational purposes only and do not imply a precision beyond two decimal points.
- The sketch shall show the baseline and the shape of the exterior face of the substructure (abutments and wingwalls). All corners shall be referenced by showing working points and station/offset referenced to the baseline. Wingwall angles to the front face of abutments shall be referenced. Working point coordinates may be shown on the plan.
- At intermediates piers, the skew angle between the centerline of the pier and the baseline is required. The location of the intersection of the pier centerline with the baseline shall be tied to other parts of the substructure by baseline dimensions. The distance from the baseline to the centerline of roadway along the centerline of the pier shall be provided. The station of the intersection points at the baseline shall be shown. Distances between the outside faces of each barrier shall be shown.
- For multi-level structures, each level shall be sketched separately, but referenced to the same baseline.
- The lay-outs sketch for box culverts shall include inside faces of walls, ends of the culvert, and the front face of the wingwalls. Reinforced concrete arch culverts, concrete rigid frames, and metal culverts shall be treated similarly.
18.104.22.168 Other Plans
The following shall be followed by the designer in the development of specific plan types that may be required:
- Proprietary Retaining Walls: When proprietary retaining walls are included in a project, provisions must be included in the contract documents to guide the suppliers of the walls. The contract documents will illustrate the general lines and grades of the proposed retaining wall along with any dead, live and earth loading which the wall design must support as well as geotechnical properties of the fill material and foundation material. During construction, the contractor will submit, through the shop drawing review process, the completed drawings and calculations of the wall design for review by the designer.
- Reinforcement Bar Schedules: A reinforcement bar schedule must be prepared whenever reinforcement is required on the project. The reinforcement bar schedule will be prepared in sufficient detail by the designer such that it can be directly utilized for construction without need for additional detailing efforts by the contractor. The preparation of the schedule shall utilize the Department’s Bridge Rebar Sheet Program (BR-10-001, 2010), which is located on the DRC – Bridges and Structures Tab. Bar marks should not be repeated. For bar marks that cover varying lengths of bar, the minimum and maximum lengths of bar shall be denoted in the schedules, along with the varying distance per number of bars. For example: S601, 9'-0" to 12'-0", vary 2 EA. by 6".
- Soil Boring Logs: The soil boring log sheet shall be prepared using the DelDOT Bridge Boring Log Program (BO-01-001, 2012). Further instructions on the use of the program are located on the DRC – Bridges and Structures Tab.
102.1.4 Bridge Number
The bridge number is a unique identification number assigned to each bridge (e.g., 1-393-441, 3-152-13A). The bridge number is assigned by the Bridge Management Engineer. The bridge number consists of the county identification number (1 = New Castle County, 2 = Kent County, and 3 = Sussex County), the unique bridge number, and finally the roadway designation number. For a new bridge, the designer should request the bridge number from the Bridge Management Engineer at the time of the TS&L submission. On bridge plans, the bridge number may omit the roadway designation number for a shorter presentation.
102.2 Special Provisions Development
Special provisions should be used to pay for an item of work if:
- There is no standard specification that covers the type of work; or
- The work is substantially different from the Standard Specifications and the differences will have a cost effect.
The use of special provisions should be minimized. Efforts should first be made to use a standard specification. However, the use of a special provision is appropriate when introducing new products or construction techniques.
The DelDOT Engineering Support is responsible for maintaining standard or modified specifications. Any special provisions needed for bid items not covered by standard or previously prepared special provisions must be prepared by the designer. The designer must coordinate the preparation and use of all project special provisions with Engineering Support.
Prior to the Semi-Final Construction Plans submission, the designer must transmit electronic drafts (in MS Word format) of all project special provisions to the Bridge Design Engineer, who will determine whether special provisions are needed or if the work can be specified via notes while using standard pay items. The Bridge Design Engineer will forward the approved special provisions to Engineering Support. Engineering Support will review the draft special provisions; correct format, context and language; and compile the special provisions book. Engineering Support will circulate the special provisions book to DelDOT Design and Construction at the time of the Semi-Final Plans Submission. Once comments received following the Semi-Final Construction Plans review are incorporated into the special provisions book by the designer, as assisted by Engineering Support, the special provisions are considered final.
Additional guidance on the preparation and formatting of special provisions is located on the DRC – Project Management Tab.
102.3 Quantities and Cost Estimates
The calculation of quantities and creation of a cost estimate is required at every stage of the design process. The project cost drives numerous decisions during the development of the design and quantity calculations and cost estimates must be prepared in a diligent manner with accurate results.
The calculation of project quantities should be developed in accordance with the DelDOT Quantity Calculations Guidelines, which is located on the DRC – Cost Estimating & Project Timing Tab. This document provides guidance on the calculation of several standard items that are commonly encountered on DelDOT projects.
DelDOT also maintains a unit cost history for all bid items that should be referenced in the development of cost estimates. Unit costs from the DelDOT history can be used as a starting point and should be adjusted to reflect project-specific characteristics, such as quantity size, project location, and site conditions. The unit cost history can be obtained on the DRC – Cost Estimating & Project Timing Tab.
102.4 Construction Schedule
A detailed construction schedule shall be prepared for each bridge project. Preparation of the construction schedule must be coordinated with Engineering Support. Specific requirements related to the development of the construction schedule, including historic production rates for various construction activities, are located on the DRC – Cost Estimating & Project Timing Tab.
For Department-designed projects, the designer should request the preparation of a Critical Path Method (CPM) schedule from Engineering Support. For consultant-designed projects, the consultant is responsible for the preparation of the Critical Path Method schedule, which must be submitted for review by Engineering Support. A draft CPM schedule should be included with the Semi-Final and Final Plan submissions and finalized for the Timing Statement for the PS&E submission.
102.5 Bridge Design Procedures
102.5.1 Quality Assurance and Quality Control
In designing bridges and other highway structures, the designer’s mission is to prepare safe, durable, and economical design solutions, produce a quality set of plans that meet the project requirements, and use details that are consistent with DelDOT practices and suitable for bidding and construction.
The development of all bridge projects should adhere to the requirements of DelDOT's current QC/QA Manual and the Bridge Design Project Development Process (see DRC - Bridges and Structures and EI-BR-21-001). The plan development checklists are also a vital element of DelDOT’s Quality Assurance / Quality Control (QA/QC) process and should be utilized for each submission. The checklists include:
- Plan Submission Checklist (DRC – Project Management)
- Concrete Girder Bridge Plan Checklist (DRC – Bridges and Structures)
- Steel Girder Bridge Plan Checklist (DRC – Bridges and Structures)
- Precast Concrete Arch or Rigid Frame Bridge Plan Checklist (DRC – Bridges and Structures)
- Precast Concrete Box Culvert (DRC – Bridges and Structures)
In accordance with the QC/QA Manual, consultants must submit a project-specific QC/QA Plan prior to commencing work on a project. The consultant QC/QA plan will be reviewed by and mutually agreed upon by DelDOT’s project manager and the consultant.
102.5.2 Designed-In Value
22.214.171.124 Alternatives Analysis
For structures requiring a TS&L submission as outlined in Section 126.96.36.199 – Type, Size, and Location Submission Requirements, the designer should evaluate several alternative bridge types. This will aid in the selection of the most appropriate structure type. At least three bridge types that pass the logical selection process should be submitted in the alternatives study included with the TS&L submission, together with a preliminary first cost/construction cost or life-cycle cost analysis (LCCA) and a final recommended bridge type.
For major and complex bridges, as defined in Section 101 – Introduction herein, a minimum of two bridge types should be studied for each: a steel and concrete alternate design. One bridge type may be accepted if a reasonable explanation is provided.
188.8.131.52 Life-Cycle Cost Analyses
For beam-type structures and structures that require a TS&L submission as outlined in Section 184.108.40.206 – Type, Size, and Location Submission Requirements, the selection of a recommended structural alternative shall be based on a first cost / construction cost or LCCA. For most structures, a first cost / construction cost analysis is used. An LCCA is used for major and complex bridges, as defined in Section 101 – Introduction herein, or as directed by the Bridge Design Engineer.
LCCAs shall be performed for bridge projects or project elements to assist in determining the best alternative. An LCCA should be included with the TS&L submission to compare the costs of each considered alternative. The following should be considered:
- Design costs
- Construction costs
- Right-of-way costs
- Routine maintenance costs
- Periodic maintenance and rehabilitation costs
- Service life (typically 100 years)
- Operating costs
- Accident costs
- User costs
An LCCA shall be performed in studying alternate design concepts to compare the benefits and costs at different times in a bridge structure’s life span. Future benefits and costs over the proposed time span of each alternative should be evaluated. A long-term perspective should be considered in programming improvements and selecting among alternative design, maintenance, rehabilitation, and reconstruction strategies in designing bridge structures. Refer to FHWA publication Life-Cycle Cost Analysis Primer (2002) available from the Office of Asset Management for more information (http://www.fhwa.dot.gov/infrastructure/asstmgmt/lcca.cfm).
102.5.3 Documentation of Design
The design of each bridge must be documented to provide a permanent reference for future use. Documentation of the design should follow the requirements of the DelDOT QC/QA Manual, which is available on the DRC – Project Management - Manuals Tab and, at a minimum, should include the following:
- Design computations
- Specific references to specifications
- Specific design criteria
- Hydraulic and hydrologic reports
- Foundation reports
- Quantity calculations
- Material properties
- Computer printouts, if the design was prepared using a computer (include the input, output, and the name and version of the software used)
- Design checklists
- Plan submission checklists
- Any design exceptions and/or design variances
The above noted items are in addition to those materials required for inclusion in the “Design Document Binder” as defined by DelDOT’s QC/QA Manual.
The documentation should be kept in notebooks or folders for permanent storage in the contract file (alternatively, electronic files, in PDF format, may be retained). Each plan submission must include a copy of the design computations and printouts for review; they must include the date and the name/initials of the designer who performed the computations and the person who checked them on each sheet. The date and the name/initials of the DelDOT reviewer will be added following review of the computations. The cover sheet for the calculations shall have signature lines for the designer, checker, and reviewer to recommend what is contained therein. In the final plan submission, consultant designers should submit all of the original documentation to the Bridge Design Engineer. Any changes to the documentation should be submitted by the time construction is completed.
102.5.4 Design Exceptions and Design Variances
Typically, designs will meet or exceed the minimum Department-governing criteria and AASHTO new construction criteria for the 13 Controlling Design Elements. Occasionally, unusual conditions may warrant consideration of a lower standard. The need for design exceptions and design variances must be identified early in the design phase, so approval or denials do not delay completion of the design or require extensive redesign. In such cases, the proposed design must be thoroughly documented for review and approval by the Department and, if required, by FHWA.
Sufficient detail and explanation must be provided to build a strong case to those reviewing design exception and design variance requests. The 13 Controlling Design Elements are considered safety related and the strongest case must be made to accept a reduction in the stated standards. At some point, this justification may be required to defend the Department’s and/or the designer’s design decisions. All deviations must be uniquely identified, located, and justified. Blanket approvals will not be granted.
Generally, a design exception or design variance can be justified if it can be shown that:
- The required criteria are not applicable to the site specific conditions.
- The project can be as safe by not following the criteria.
- The environmental or community needs prohibit meeting criteria.
Most often a case for approval of a design exception or design variance is made by showing the required criteria are impractical and the proposed design wisely balances all design impacts. The impacts usually compared are:
- Operational impacts
- Impacts on adjacent section
- Level of service
- Safety impacts
- Long term effects
- Cumulative effects
A justification should not be made solely on the basis that:
- The Department can save money.
- The Department can save time.
- The proposed design is similar to other designs.
The Design Exception and Design Variance Request Forms (Figure 102‑1 and Figure 102‑2) shall be used to document requests for deviations. The designer must provide all the supporting rationale (e.g., the necessary design criteria, figures, calculations, cost analyses, accident records, mitigation costs, photographs, plan sheets) for each request in sufficient detail to document the request. The Design Control Checklist (Figure 102‑3) and the Design Criteria Form (Figure 102‑4) should be included in the documentation, if applicable. The Design Criteria Form applies to new construction or 4R projects. A project note shall be included in the plans listing the items that have approved design exceptions and/or design variances.
The FHWA has delegated the responsibility for the review of design exceptions and/or design variances for designs both on and off the NHS to DelDOT. FHWA will review only for projects meeting the following criteria:
- A project that is identified as a PoDI and for which the design has been chosen for oversight; or
- The project is unique and the Department requests FHWA involvement.
102.5.5 Chronology of Submissions
The chronology of the bridge-related submissions for approval shall be made as indicated on the Plans Submission Checklist (DRC – Project Management), as detailed in the Bridge Design Project Development Process (DRC - Bridges and Structures), and as follows:
- Preliminary Design
- Draft hydrologic and hydraulic (H&H) report (if applicable) (see Section 104 – Hydrology and Hydraulics)
- Draft scour evaluation report (if applicable) (see Section 104 – Hydrology and Hydraulics)
- Conceptual TS&L plans
- Draft foundation report (see Section 105 – Geotechnical Investigations)
- Concept Plans (interim submission)
- Preliminary Construction Plans
- Final H&H report
- Final scour evaluation report
- Final foundation report
- Semi-Final Construction Plans
- Final Construction Plans
102.6 Preliminary Design
102.6.1 Hydrologic and Hydraulic Report
An H&H report is required for any bridge over a stream or tidal area. The report must provide a hydraulic analysis, flood profiles for the various design years, and recommendations. Preparation of the H&H report and design year criteria are covered in Section 104 – Hydrology and Hydraulics.
102.6.2 Scour Evaluation Report
A scour analysis is required for any structure over a stream or tidal area. The report must include the scour calculations and recommended countermeasures, as well as include other details of the evaluation. Preparation of the scour evaluation report and analysis procedure is covered in Section 104 – Hydrology and Hydraulics. The scour analysis and recommendations are typically included with the Hydrologic and Hydraulic Report.
102.6.3 Foundation Reports
Foundation reports are required for all structures. Geotechnical investigations and the foundation report preparation must be completed in accordance with Section 105 – Geotechnical Investigations. Following the completion of a subsurface exploration program, the DelDOT Geotechnical Engineer will prepare a geotechnical data report for use by the designer in developing the foundation design. The foundation report must be prepared to evaluate and recommend foundation design parameters and a foundation type. Among other items, the foundation report shall include the soil bearing capacity, the type of foundation, and, if piles are recommended, the type and size of piles.
102.6.4 Conceptual Type, Size, and Location Plans
Conceptual plans prior to the submission of TS&L plans are only required on major or complex bridge projects or at the discretion of the Bridge Design Engineer. When conceptual TS&L plan submissions are required, the following items must be submitted:
- Conceptual TS&L Plan(s) that include:
- Plan and elevation
- Typical Sections
- Structure type
- Span lengths
- Conceptual TS&L Report that includes:
- Beam design calculation (can be based on available design charts)
- Basic bridge geometry (to demonstrate required clearances within 6 inches)
- Cost comparison of considered alternatives
- Subsurface investigation requirements (i.e., geotechnical data report per Section 105 – Geotechnical Investigations)
- Preliminary hydraulics and hydrologic report (if applicable) (see Section 104 – Hydrology and Hydraulics)
102.6.5 Type, Size, and Location Submission
The investigation of a proposed structure shall be sufficiently thorough to objectively select and justify the TS&L on the basis of the information available from the various phases of study, including any foundation information obtained. Preliminary cost comparisons shall be made to support the TS&L recommendations. The TS&L submission must be forwarded to the FHWA for review when required for PoDI oversight projects.
220.127.116.11 Type, Size, and Location Submission Requirements
Structures with an estimated cost of $1 million or greater require a formal TS&L submission. TS&L plans may be required on other projects at the discretion of the Bridge Design Engineer. For design of state-funded projects and smaller Federal-aid projects, the TS&L submission and approval process is incorporated into the standard Preliminary Construction Plans submission and review procedures.
The TS&L submission consists of a TS&L plan(s) and a TS&L alternatives study report. The following information shall be included for a TS&L submission:
- TS&L Plans: The following information shall be shown on the TS&L plan(s):
- Plan view, including controlling clearances, span length, skew, existing contours and finished contours, scupper locations, and end structure drainage, where required;
- Elevation view showing controlling clearance, span length, existing and finished ground line, continuity, support condition (fix/expansion), type and movement classification of expansion dams, type of bearings, and protective fence locations;
- Cross-section showing out-to-out dimension, traffic lanes, shoulder widths, beam type, size and spacing, overhangs, cross-slope, superelevation, minimum slab thickness, type of traffic or pedestrian barrier, thickness of wearing surface, and protective fence;
- Typical sections showing limits of individual construction stages, for cases where construction of the bridge is required to be performed in stages; locations of longitudinal joints in the deck; locations and the type of temporary barriers; and traffic lane locations and widths;
- Elevation view of pier(s) showing proposed configuration, where required;
- Deck protective system (for rehabilitation projects only);
- Loading, design, and analysis method; and non-standard details;
- Soil boring locations;
- Hydraulic information, including design flood data, flood of record and date, slope protection, where required, and preliminary scour information;
- Horizontal and vertical curve data for all roadways (and railroads as applicable);
- For retaining walls, the length and height for each segment (note that the TS&L for walls will not be approved until the foundation recommendation is provided);
- Bridge-mounted lighting poles, sound barriers, and signs, if required.
- TS&L Report: The report should address alternates studied and justification for the recommended bridge type, as well as include the following:
- Cost comparison for all types considered during the TS&L study. The cost estimate shall be arranged to indicate total cost per substructure unit and major portions of superstructure (e.g., rolled beam span, plate girder span). Cost comparisons should also be prepared to consider the total project cost, which reflects non-bridge costs that may be affected for each respective bridge alternative. For bridge replacement projects, the cost data should include a cost comparison for the rehabilitation of the existing structure. Likewise, for major bridge rehabilitation projects, cost data should include a cost comparison for a replacement structure.
- Justification for recommended alternate.
- Address the need to account for future widening and future redecking requirements of the recommended bridge.
- Pedestrian count information concerning possible future development that might warrant need for sidewalks and/or pedestrian protective fence.
- For the recommended bridge type, beam design calculations for the controlling interior and fascia beam; geometry calculations sufficient to confirm the vertical and horizontal clearances; deck drainage calculations; and expansion joint movement calculations.
- Constructability discussion for major and/or complex structures.
- The preliminary foundation report and calculations.
- If applicable, preliminary H&H report and calculations, and preliminary scour analysis.
- Plan submission and girder type checklist (for the recommended structure) completed for the TS&L submission.
- Completed Project Design Control Checklist Form (Figure 102‑3) and Design Criteria Form (Figure 102‑4).
- For rehabilitation projects:
- Age of existing structure, present and cumulative average daily truck traffic (ADTT), portion to be replaced, type of steel for steel bridges, date of last inspection, type of diaphragm connections (i.e., welded or riveted), type and location of deterioration, deck drainage, expansion dam type, barrier type, and other pertinent items.
- Live load ratings of the bridge at present and after rehabilitation.
- Fatigue-prone details, such as out-of-plane bending problem areas, cover-plated beams, remaining fatigue life with and without retrofit, fatigue problems observed during inspection, recommended retrofit for existing fatigue-prone details, and other pertinent items.
- Proposed scope of work.
- For structures involving the railroad:
- Railroad right-of-way cross sections (500 feet on each side of the proposed structure), degree of track curvature, and rate of superelevation, if applicable.
- Investigation and description of existing railroad drainage facilities and conditions in the vicinity of the structure site.
- A copy of the railroad company’s letter of approval of acceptance regarding horizontal and vertical clearances as well as a request for temporary support of railroad tracks, if required.
- Demolition procedures, including a schematic plan, shall be provided for the removal of structures over or adjacent to railroads. The procedures and schematic must be coordinated with the railroad representatives.
102.7 Preliminary Construction Plans
The submissions required at the preliminary plan stage are as follows:
- Preliminary structure plans
- Preliminary structure calculations
- Preliminary structure cost estimate
- Preliminary special provisions for unique items
- Final geotechnical and foundation reports
- Final hydraulics report (if applicable)
- Final scour analysis (if applicable)
At this stage of design, core structure calculations, such as beam designs, bridge geometry, and foundation design (i.e., footing dimensions and/or pile types and sizes), should be finalized and checked.
Preliminary structure plans shall be developed to a level of detail commensurate with that required by the Plan Submission Checklist and applicable Girder Type Submission Checklist (available on the DRC – Project Management Tab and the DRC – Bridges and Structures Tab respectively). The preliminary structure plans should include the items required for a TS&L plan submission (see Section 18.104.22.168 – Type, Size, and Location Submission Requirements) in addition to the items noted below:
- Existing utilities
- Limits of construction (LOC)
- Existing right-of-way
- Proposed right-of-way
- Erosion and sediment control measures
- Environmental compliance measures
When determining the limits of construction, the designer should consider the temporary and permanent impacts due to erosion and sediment control facilities, existing and proposed utilities, and construction staging. The coordination required at the Preliminary Construction Plans stage of design is specified in the Project Development Manual (PDM; 2015) and the Plan Development Process.
The Preliminary Construction Plans submission must be forwarded to the FHWA for review when required for PoDI oversight projects.
102.8 Semi-Final Construction Plans
The Semi-Final Construction Plans are approximately 85 percent complete along with specifications, quantities, and cost estimates. The submission includes everything required for a complete design, except final quantities. At this stage of design, all structure calculations should be finalized and checked.
Semi-final structure construction plans shall be developed to a level of detail commensurate with that required by the Plan Submission Checklist and applicable Girder Type Submission Checklist.
Bridge load ratings shall be prepared and submitted at this stage of design. The load ratings and accompanying information shall be prepared in accordance with the requirements of Section 108 – Bridge Load Rating.
All bid items must be listed at this stage of design. Estimated quantities for the bid items may not be final for this submission.
Included with this submission should be a draft of all special provisions and a construction schedule.
A cost estimate based on the semi-final design quantities is prepared as a check on the initial cost estimate. The designer should advise the Bridge Design Engineer of any significant changes in the estimated cost of the project.
The Semi-Final Construction Plans submission must be forwarded to the FHWA for review when required for PoDI oversight projects.
102.9 Final Construction Plans
Final Construction Plans are an update of semi-final plans and should be considered a 100 percent complete design. Final Construction Plans are distributed to the various Department units solely to collect final statements and are not generally commented upon. Final Construction Plans include:
- Final structure plans
- Final structure quantities, including checked calculations
- Prepared and checked structure design calculations
- Final bridge load ratings
- Final construction schedule
- Final special provisions
- Cost Estimate
The designer must incorporate into the plans all requirements specified in statements, agreements, and permits (e.g., towns, utilities, railroads, right-of-way, environmental). The terms of the permits and acquisitions are defined in the project agreements. Some conditions in the project agreements may affect the project design and the requirements placed on the contractor. Designers must review all project agreements to ensure that all requirements are included in the plans.
The Department maintains a unit cost history for all bid items. Unit costs from this history should be used as a starting point for the project cost estimate. These unit costs should be adjusted for project characteristics such as quantities, location, and site conditions.
One copy of the final plans, quantity calculations, and time estimate should be sent to Construction and Engineering Support for review at the final plan stage.
The Final Construction Plans submission must be forwarded to the FHWA for review when required for PoDI oversight projects.
102.10 Plans, Specifications, and Estimate
The PS&E submission is the final step before advertising the project for bid. All submissions are directed to the PS&E Coordinator in Engineering Support.
- The designer submits the final plans and estimates. Cost estimates must be submitted electronically using the Department’s engineering software, AASHTOWare.
- PS&E Plans must be submitted in PDF file format in accordance with the CADD Standards Manual (Wiki Format).
- The DelDOT Engineering Support submits the completed special provisions.
- All other DelDOT sections (Traffic, Environmental Studies, Utilities, Railroad, and Real Estate) submit their statement for advertisement.
When Engineering Support receives all of the necessary submittals, they are sent to Contract Administration for project advertisement.
102.11 Bid-Cycle Requirements
Addenda are design changes that are made between the time the project is advertised for bid and the opening of bids.
Because contractors must have time to prepare their bids, addenda cannot be accepted later than 5 calendar days, as dictated by the Department, before the bid opening date. Addendum changes of major significance after that date may require that the project bid opening be postponed or canceled and re-advertised.
Attention should be drawn to changes made to plans by way of an addendum by clouding the change and identifying the change consistent with the addendum number (e.g., ADD 1). The cloud should be accompanied by the addendum symbol, which is a triangle with the addendum number inside. Addenda should be noted in the revision block of the applicable plan sheet. This revision block notation should include the date of the addendum and initials of individual responsible for the addendum.
A new right-of-way statement is required for any addenda that require additional right-of-way.
102.11.2 Bid Opening and Bid Review
Following the bid opening, DelDOT Contract Administration reviews the bids to identify any irregularities. The bid tabulations are typically forwarded to the designer within 1 day of the bid opening. The designer must receive a copy of the bid tabulations for review. The designer shall review the bid prices and total cost against the engineer’s estimate and determine whether there are any unbalanced bids (DelDOT personnel should refer to Policy Implement Number D-08 : Bid Analysis and Recommendation to Award Procedures (DelDOT P.I. D-08), which provides the specific steps to be used in the review of bids). Refer to the Standard Specifications for criteria for unbalanced bids. Individual item bid prices that are 20 percent higher or lower than the estimated costs require analysis and possible discussion with the low bidder in the form of a pre-award meeting.
DelDOT, n.d. CADD Standards Manual, (Wiki Format).
DelDOT, n.d. Quantity Calculation Guidelines.
DelDOT, 2009. Quality Assurance/Quality Control Plan, Division of Transportation Solutions, January 2009.
DelDOT, 2010. Plan Development Process, December 22.
DelDOT, 2010. Rebar Sheet Program, Engineering Instruction BR-10-001, April 22.
DelDOT, 2012. Boring Log Program, Engineering Instruction BO-01-001, November 27.
DelDOT, 2015. Project Development Manual, July.
DelDOT, 2018. Policy Implement Number D-08: Bid Analysis and Recommendation to Award Procedures, October 19.
FHWA, 2002. Life-Cycle Cost Analysis Primer, Office of Asset Management, August.