Bridge and Structures Design Manual - Welcome to The GDOT

1 Bridge and Structures Design Manual 8/10/2018 Revision Atlanta, georgia 30308 Bridge and Structures Design Manual State of georgia department of transportation Disclaimer This Manual is intended to be an aid to designers working on projects for the georgia department of transportation . It is not to be used as a substitute for sound engineering practice and will be used at one s own risk. The georgia department of transportation and the authors of this document are not responsible for the consequences of the use and misuse of the contents of this document. The latest version of this document is available at: Other helpful links: GDOT Bridge Design Home Page: GDOT Bridge Design Software: #tab-3 GDOT Bridge Microstation Customization: #tab-2 GDOT Bridge Design Basic Drawings: #tab-1 Please send constructive comments to the Bridge Design LRFD Committee care of Stanley Kim: Page i Acknowledgement The original Bridge and Structures Design Manual was created through the public-private partnership of the georgia department of transportation and the Consulting Engineering Companies of georgia .

2 This document was modified from the original Design Manual for inclusion of LRFD material and general content by georgia department of transportation personnel. The following people have donated their time and resources to contribute to the quality of transportation engineering in georgia : LRFD Design Committee Y. Stanley Kim, PhD, GDOT Douglas D. Franks, GDOT Steven K. Gaston, GDOT Donn P. Digamon, GDOT Design Committee for Original Document Paul V. Liles, Jr., GDOT Ted Cashin, GDOT Al Bowman, The LPA Group Incorporated John Heath, Heath and Lineback Engineers Greg Grant, Wolverton and Associates Contributing Authors to Original Document Bob Mustin, GDOT John Tiernan, GDOT John Durand, Parsons Brinckerhoff Page ii Intentionally Left Blank Bridge and Structures Design Manual Page iii Revision Summary Revision Number Revision Date Revision Summary LRFD Bridge Manual Original 7/8/13 Original Release Date 10/1/13 Section - Removed after all necessary grinding from 8 overhang thickness; Removed (LRFD ) from 8 overhang thickness Section - Changed LRFD reference from Table 4A-1 to Table A4-1 Section - Modified tower bent placement directive; Added pile fixity assumption Section - Removed Commentary 6/2/14 Section - Updated LRFD Specification to 6th edition, 2012.

3 Updated georgia Standard Specification to 2013; defined all bridges as typical Section - Allowed Standard Specification widening of Existing Standard Specification bridges Section - Changed office responsible for Survey Manual Section - Added LRFD software submittal requirements for consultants Section - New section added - Set minimum beam requirement for bridges with vehicular traffic Section - Added reference to online slab Design program Section - Changed placement and spacing of temperature steel in top mat of deck Section - Clarified urban area locations Section - Edited height of fence Section - New section added limiting coping thickness to 6 Section - Check clearance between cap and PSC beam when plain pads are used Section - Added new section - Directive to minimize number of pad designs for Bridge Section - Specified use of kips in lieu of tons or pounds for foundations Section.

4 - Added maximum factored resistances and stresses for all pile types Section - Restricted use of spirals in caisson; limited ties to maximum size of #6; Stated seismic detailing at fixity is not required in caissons Section - Added limits for depth to width Bridge and Structures Design Manual Page iv ratio of intermediate caps; Changed cap width increment to 3 Section - Modified longitudinal rebar in riser of intermediate bents to # 5 Section - Removed railroad from vehicular collision consideration Bridge Design Manual Original 1/26/15 General - Incorporated Standard Specification guidance from GDOT Bridge and Structures Design Manual into LRFD Bridge Manual to produce a consolidated Manual Section - Added requirement to submit Design calculations in PDF format Section - Added guidance for when a deck section is required on preliminary layouts Section - Removed direction about railroad shoring review Section - Added reference to Section - Revised requirement for epoxy reinforcement Section - Removed requirement for grooving under medians Section - Modified description of new curved fence detail Section - Clarified directive for the use of handrail or fence on parapets Section - Removed restriction on use of

5 Diameter strands Section - Limited coping thickness to be used for composite properties Section , - Limited beam spacing to 9 -0 Section - Added the use of weathering steel Section - Added provisions for use of steel diaphragms for concrete beams Section - Revised Drainage Manual reference Section - Modified Factored Axial Load note Section - Clarified directive on use of 50 ksi H-piles versus 36 ksi H-piles Section - Removed 12 PSC piles from Table Section - Added 20 and 24 metal shell piles to Table Bridge and Structures Design Manual Page v Section - Added 5 clear spacing as minimum for stirrups and vertical bars in caissons Section - Modified wingwall length requirement Section - Increased minimum stirrup spacing to 5 Section - Added 4 minimum stirrup spacing requirement for columns Section - Revised Table to change Modular Walls to Modular Block Walls Section - Limited Modular Block Wall Design height to 20 feet Section - Modified when Bridge plans require a

6 Revision mark Section - Added direction about railroad shoring review Section - Added directive to include Seismic Zone and SD1 on General Notes sheet 5/5/15 Section - Updated LRFD Specification to 7th Edition, 2014 Section - Removed Guide Specification reference; contact Bridge Office for guidance Section - Added for vertical clearances to be satisfied for travelway Section - Added that draped strands shall not be placed in the top 8 of beam Section - Added guidance in reference to information needed in Bridge plans for field measurement of driving resistance for piles for LRFD projects. Section , - Added guidance that need not apply to side faces of bent caps less than or equal to 2 foot high. 7/31/15 Reformatted Manual to standard template 1/25/16 Section Added restriction for modifying title block Section expanded/clarified guidance for consultant QA/QC Section - Added guidance for re-request for Bridge condition surveys Section - clarified span limit for pile bents for AASHTO PSC beams only Section - Added reference to beam length limits Section - changed title and added 1 difference limit for overhang Section - Added section for beam length Bridge and Structures Design Manual Page vi guidance Section Changed to include new precast beam types Section - Added steel orientation guidance Section - Added steel orientation guidance Appendix 3B Changed beam charts for new beam length limits Section Waived LRFD for bottom of caps Section Added 6 minimum stirrup spacing Section Waived LRFD for bottom of caps Section (g)

7 Revised coping names to match pay items Fig. revised to show sloping paving Fig. 9B-1 Revised to show cross-ties for plastic hinge regions 10/26/16 Chapter 2 -Modified temporary vertical clearance for falsework Chapter 3 - Set maximum 28-day concrete strength for PSC beams to ksi. Removed with Bridge Office Approval clause. Rewrote top strand pull force guidance for clarity Chapter 4 - Added guidance to place top mat of steel in all spread footings. Added guidance to place top mat of steel in seismic pile footings Chapter 8 - Defined lap splice requirements for welded wire fabric 7/11/17 Section Added guidance for application of truck-train loading Section Updated sq. ft costs Section removed cost references for steel beams Section Added requirement for quantities on Design -build projects Section Added limit for stirrup clear spacing in anchorage zone Table Updated span limits for cored slabs and box beams Section Added need for galvanization of steel diaphragm and rearranged guidance for use Section Defined what is deemed a visible area Section Added reference for utilities through MSE walls Bridge and Structures Design Manual Page vii Section Added limits of utility pipe sizes based on beam depths Section Section added for stiffness approach and re-organized Section Modified guidance for HPC and stainless steel use in PSC piles Section Guidance for allowable settlement and keying spread footings Section Clarified zero uplift check Section Added.

8 Alternate foundation types Section Modified 2 column bent guidance to 60 ft Section Removed guidance that cap should extend beyond bottom edge of beam Section Added additional guidance for applying collision load to columns Section Added guidance for use of general note for special finish for navigable water bridges Section Section added for MSE wall Design requirements Section (d) Added reference Section wall plans to be drawn to equal vertical and horizontal scales. Section Added sentence to follow section for walls Sections and Re-organized to add subsections for information 10/13/17 Cover - Added Donn Digamon to the list of active committee members Section - Reduced gross haul weight requiring routing investigation Section - Added vertical clearance requirements for bridges over mixes use trails Section - Revised the square foot cost for PSC beams on concrete bents Section - Revised the rounding integer for pile quantities Move subsection to Section - Added directive to add note for minimum lap of 2'-2" on stirrup bars in barriers/parapets Section - Added requirement for lateral stability check by EOR when beam limits are exceeded.

9 Table - Modified to eliminate using Bridge and Structures Design Manual Page viii unreinforced pads for Type I Mod beams Section - Revised title to read Width and Length and set minimum pad length to 9inches Section - Added requirements for end bent cheek walls Section - Deleted guidance on mismatched wingwall lengths Section - Prohibited the use of single legged stirrups Section - Relocated from Section - Added requirements for wall plans Section - Added requirements for wall plans Chapter 6 - Corrected chapter title Section Fig - Revised figure to match directive 2/23/18 Chapter 2 - Added guidance regarding horizontal Bridge clearance for future lanes. - Revised the integer to which pile quantities shall be rounded. Chapter 3 - Revised statement explaining minimum slab thickness table. - Set minimum difference between initial and final concrete strength for PSC beams. - Added requirement to fill PSC strand pattern from bottom up.

10 - Revised steel diaphragm requirements Added subsection on diaphragm materials, including necessary General Notes. - Removed option of 1/2in unreinforced pads under Type 1 Mod beams. Chapter 4 Specified that Service Limit State should note control size or Design of elements. - Revised the integer to which pile quantities shall be rounded. Restricted the use of stirrups as a means to control shear in spread footing. Restricted the use of stirrups as a mean to control shear in pile footings. Chapter 5 Removed New Jersey Barrier option from Traffic Barrier H, modified Design loading, and revised figure. Bridge and Structures Design Manual Page ix Added guidance on estimating right of way need behind tie back walls. Added guidance on estimating right of way need behind soil nail walls. 6/7/18 Chapter 2 Section Corrected Hydraulics Manual Chapter Reference Chapter 3 Section guidance on payment for steel diaphragms.