commonwealth of pennsylvania department of transportation · 2019-09-12 · commonwealth of...
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COMMONWEALTH OF PENNSYLVANIADEPARTMENT OF TRANSPORTATION
STANDARD
WITH REFINED METHODS OF ANALYSIS
CROSS FRAME AND SOLID PLATE
DIAPHRAGMS FOR STEEL BEAM/GIRDER
BRIDGES DESIGNED
BD-619M
SHEET 1 OF 5
CHIEF BRIDGE ENGINEER
RECOMMENDEDRECOMMENDED
BUREAU OF PROJECT DELIVERY
S
ANY SPAN LENGTH
RECOMMENDED ACCEPTABLE AVOID
ANY NONE
ANY SPAN LENGTH
RECOMMENDED ACCEPTABLE AVOID
NLF
S
TDLF OR SDLF
RECOMMENDED ACCEPTABLE AVOID
NLF
S
SPAN LENGTHS 200 FEET
SPAN LENGTHS 200 FEET
TDLFSDLF
SDLF TDLF & NLF
MAX
RECOMMENDED ACCEPTABLE AVOID
SDLF
BRIDGES WITH RADIAL OR SKEWED SUPPORTS
MAX
ALL OTHER CASES NLF TDLF
(INCLUDING BRIDGES WITH L/R IN ALL SPANS LESS THAN 0.03 +/-)
RECOMMENDED FIT CONDITIONS FOR STRAIGHT I-GIRDER BRIDGES1
TDLFSDLFNLF
SKEWED BRIDGES WITH SKEW 70 DEGREES +/- AND I 0.30 +/-
SKEWED BRIDGES WITH SKEW 70 DEGREES +/- AND I 0.30 +/-
NON-SKEWED BRIDGES AND SKEWED BRIDGES WITH SKEW 70 DEGREES +/-
1
2
[(L/R) 0.03 +/-]
RECOMMENDED FIT CONDITIONS FOR HORIZONTALLY CURVED I-GIRDER BRIDGES
AND (L/R) 0.1 +/-
LARGE SPAN LENGTHS 250 FEET +/-
NOTES FOR DESIGNING AND DETAILING DIAPHRAGMS
S
NOTES FOR DESIGNING AND DETAILING DIAPHRAGMS, CONTINUED ON SHEET 2* *
REFERENCE DRAWINGS
BC-753M STEEL GIRDER DETAILS
STRUCTURES (STRAIGHT GIRDERS ONLY )
BC-754M STEEL DIAPHRAGMS FOR STEEL BEAM/GIRDER
CONNECTION LOCATION. PROVIDE ROTATION VALUES FOR EACH GIRDER.
DEAD LOAD OUT-OF-PLANE GIRDER ROTATIONS AT THE GIRDER TENTH POINTS AND AT EACH DIAPHRAGM
SURFACE EXCEEDS 0.005 RADIANS, PROVIDE A TABLE IN THE CONSTRUCTION DRAWINGS SHOWING THE TOTAL
b) WHERE THE MAXIMUM OUT-OF-PLANE GIRDER ROTATIONS DUE TO ALL DEAD LOADS, EXCLUDING FUTURE WEARING
SUCCESSFULLY ERECTED IF THE FIT-UP FORCES ARE MANAGEABLE.
ERECTED USING SOME FORM OF TEMPORARY SHORING CAN BE DETAILED FOR SDLF OR TDLF AND
ERECTED IF THE FIT-UP FORCES ARE MANAGEABLE. LIKEWISE, BRIDGES WHICH ARE TO BE
BRIDGES ERECTED WITHOUT TEMPORARY SHORING CAN BE DETAILED FOR NLF AND SUCCESSFULLY
AND MAGNITUDE OF THESE FORCES ARE ALSO INFLUENCED BY THE USE OF TEMPORARY SHORING.
WHICH THE ERECTOR MAY NEED TO APPLY TO ASSEMBLE THE STRUCTURAL STEEL. THE NATURE
MAGNITUDE OF THE BRIDGE'S INTERNAL DEAD LOAD FORCES AND OF THE "FIT-UP" FORCES
SECTION 6, APPENDIX E6, THE CHOICE OF DETAILING METHOD AFFECTS THE NATURE AND
SHORING CANNOT BE USED. AS DISCUSSED IN THE DESIGN AND ANALYSIS SECTION OF DM-4
TEMPORARY SHORING, NOR DOES THE USE OF SDLF OR TDLF DETAILING IMPLY THAT TEMPORARY
2 THE RECOMMENDATION TO USE NLF DETAILING DOES NOT NECESSARILY IMPLY THE NEED TO USE
DISPLACEMENTS BECOME LARGE.
BETWEEN PREDICTED FORCES AND DISPLACEMENTS THAN SDLF WHEN THE STEEL DEAD LOAD
THE NORMAL ANALYSIS METHODS USED IN THE DESIGN AND WILL PROVIDE A BETTER MATCH
FORCES CAN BECOME SIGNIFICANT AS SPANS GET LONGER AND RADII GET SMALLER. NLF MATCHES
NLF ABOVE THIS LENGTH BECAUSE A LIMITED STUDY OF THESE BRIDGES SHOWS CROSS FRAME
UNIVERSAL FOR LONG SPAN CURVED I-GIRDER BRIDGES. THE RECOMMENDATION TRANSITIONS TO
CURVED BRIDGES IS BASED ON MANY YEARS OF PRACTICE: USE OF SDLF HAS BEEN ALMOST
OF THE GIVEN BRIDGE. THE RECOMMENDATION OF SDLF UP TO ABOUT 250' FOR HORIZONTALLY
SHOULD BE EVALUATED IN THE FULL CONTEXT OF THE GEOMETRIC AND STRUCTURAL COMPLEXITY
LENGTH, SKEW, AND CURVATURE LIMITS SHOULD BE CONSIDERED APPROXIMATE GUIDELINES AND
1 FOR THE VARIOUS RECOMMENDED FIT CONDITIONS PRESENTED IN THE TABLES ABOVE, THE SPAN
I = SKEW INDEX, SEE NOTE 7 OF THIS STANDARD FOR DEFINITION.
R = RADIUS OF CURVATURE AT BRIDGE CENTERLINE.
L = ACTUAL SPAN LENGTH, BEARING TO BEARING ALONG THE CENTERLINE OF THE GIRDER.
FUTURE WEARING SURFACE ).
WEIGHT OF STEEL, WEIGHT OF DECK SLAB AND WEIGHT OF SUPERIMPOSED DEAD LOADS, BUT NOT INCLUDING
TDLF = TOTAL DEAD LOAD FIT. GIRDER WEBS VERTICAL (PLUMB ) AFTER ALL DEAD LOADS ARE APPLIED (INCLUDING
GIRDER WEBS VERTICAL (PLUMB ) WITH ALL TEMPORARY SHORING REMOVED.
OF STRUCTURAL STEEL ) BUT PRIOR TO DECK PLACEMENT. IF TEMPORARY SHORING WAS USED, SDLF IMPLIES
SDLF = STEEL DEAD LOAD FIT. GIRDER WEBS VERTICAL (PLUMB ) WHEN STEEL DEAD LOADS ARE APPLIED (WEIGHT
SHORING IS PROVIDED TO ACHIEVE OR APPROXIMATE ZERO VERTICAL DEFLECTIONS )
NLF = NO LOAD FIT. GIRDER WEBS VERTICAL (PLUMB ) UNDER NO LOAD CONDITIONS (I.E., WHEN TEMPORARY
DEFINITIONS:
IN THE TABLES BELOW.
a) GIRDERS SHALL BE DESIGNED AND DETAILED SUCH THAT THE GIRDER WEBS ARE VERTICAL (PLUMB ) AS SPECIFIED
3. DETAILING REQUIREMENTS
PUBLICATION NO. FHWA-IF-12-052-VOL 13, NOVEMBER 2012 (FHWA SBDH).
b) FEDERAL HIGHWAY ADMINISTRATION, STEEL BRIDGE DESIGN HANDBOOK, VOLUME 13, BRACING DESIGN,
a) AISC SPECIFICATION FOR STRUCTURAL STEEL BUILDINGS, ANSI/AISC 360-10, JUNE 22, 2010 (AISC SPEC ).
2. REFERENCES
c) PENNDOT SPECIFICATIONS, PUBLICATION 408 (PUB 408 ).
b) PENNDOT DESIGN MANUAL, PART 4 (PENNDOT DM4 ).
a) AASHTO LRFD BRIDGE DESIGN SPECIFICATIONS (AASHTO LRFD ).
1. DESIGN SPECIFICATIONS
HORIZONTAL (CHORD ) MEMBERS WOULD OTHERWISE BE REQUIRED FOR A TYPE X DIAPHRAGM.
FORCE EFFECTS AND/OR IN CASES WHERE GIRDERS ARE TIGHTLY SPACED AND LARGE DIAGONAL AND
SOLID PLATE: SOLID PLATE DIAPHRAGMS SHOULD BE USED WHEN REQUIRED TO ADDRESS HIGH DIAPHRAGM
REMOVED FROM THEIR FABRICATION JIG AND INVERTED TO WELD THE SECOND DIAGONAL.
ii. MINIMIZING SHOP HANDLING OF DIAPHRAGMS BY USING TYPE K DIAPHRAGMS WHICH DO NOT NEED TO BE
MEMBERS AS CLOSE TO 45° AS POSSIBLE.
i. ACHIEVING A GENERAL EFFICIENT ANGLE BETWEEN DIAPHRAGM DIAGONAL AND HORIZONTAL (CHORD )
TYPE X OR TYPE K DIAPHRAGMS MAY BE USED. SECONDARY CONSIDERATIONS INCLUDE:
IN CASES WHERE THE RATIO OF GIRDER SPACING "S" TO GIRDER DEPTH "D" IS BETWEEN 1.0 AND 1.5, EITHER
DEPTH "D" IS 1.5 OR GREATER (S/D 1.5 ).
TYPE K: TYPE K DIAPHRAGMS SHOULD BE USED IN CASES WHERE THE RATIO OF GIRDER SPACING "S" TO GIRDER
DEPTH "D" IS 1.0 OR LESS (S/D 1.0 ).
TYPE X: TYPE X DIAPHRAGMS SHOULD BE USED IN CASES WHERE THE RATIO OF GIRDER SPACING (S) TO GIRDER
INTERMEDIATE DIAPHRAGMS
SKEW, VARIABLE GIRDER SPACING, ETC.) MAY WARRANT A DEPARTURE FROM THESE GUIDELINES.
DIAPHRAGM TYPES SHOULD BE SELECTED BASED ON THE FOLLOWING GUIDELINES. SPECIAL CONDITIONS (VARIABLE
5. SELECTION OF DIAPHRAGM TYPE
LOCATIONS FOR TWO AND THREE GIRDER SYSTEMS.
m) PROVIDE CONNECTION PLATES ON THE OUTSIDE FACE OF FASCIA GIRDERS AT INTERMEDIATE DIAPHRAGM
SPECIAL DETAILS FOR SKEW ANGLES LESS THAN 25°.
l) THE DIAPHRAGM CONNECTION PLATE DETAILS SHOWN ARE VALID FOR SKEW ANGLES 25° TO 90°. PROVIDE
GEOMETRY. REFER TO SECTION 1105.03(t) OF PENNDOT PUB 408 FOR MINIMUM BENT RADII.
k) FOR SKEWED CONNECTIONS, THE DESIGNER SHOULD VERIFY THE PRACTICALITY OF BENT CONNECTION PLATE
j) COORDINATE BEARING STIFFENER AND CONNECTION PLATE LOCATIONS WITH DETAILS OF BEARING TO GIRDER CONNECTIONS.
CONNECTION PLATE MAY BE PLACED BEHIND THE BEARING STIFFENER TO MINIMIZE THE OFFSET.
CONNECTION COMPONENTS SO AS TO CREATE MINIMUM OFFSET FROM THE CENTERLINE OF BEARINGS. DIAPHRAGM
i) PLACE END DIAPHRAGMS APPROXIMATELY PARALLEL TO THE CENTERLINE OF BEARINGS. POSITION END DIAPHRAGM
OTHER ACCEPTABLE PROVISIONS FOR JACKING ARE INCORPORATED INTO THE DESIGN.
h) END DIAPHRAGMS SHOULD BE DESIGNED TO ACCOMODATE JACKING OF THE GIRDERS FOR BEARING REPLACEMENT UNLESS
g) END DIAPHRAGMS ARE REQUIRED AT THE ENDS OF GIRDERS TO SUPPORT THE EDGE OF DECK AND THE EXPANSION JOINTS.
OF PROJECT DELIVERY, BRIDGE DESIGN AND TECHNOLOGY DIVISION FOR REVIEW PRIOR TO BEGINNING FINAL DESIGN.
f) FOR CASES OF UNUSUALLY COMPLEX FRAMING AND/OR SEVERE GEOMETRY, SUBMIT A PROPOSED FRAMING PLAN TO THE BUREAU
SKEWS LESS THAN 70°.
PLACE PIER DIAPHRAGMS PARALLEL TO THE SKEW FOR SKEW ANGLES OF 70° TO 90°, OR NORMAL TO THE GIRDER FOR
INTO THE SUPPORT; RESUME PLACEMENT OF CONTIGUOUS RADIAL DIAPHRAGMS IN THE NEXT ADJACENT BAY. GENERALLY
IN THE IMMEDIATE VICINITY OF THE SKEWED SUPPORTS TO OMIT DIAPHRAGMS THAT WOULD OTHERWISE FRAME DIRECTLY
e) WHEN DIAPHRAGMS ARE PLACED RADIAL TO THE GIRDER IN CURVED AND/OR SKEWED BRIDGES, IT MAY BE ADVANTAGEOUS
GIRDERS AND IN CONTIGUOUS LINES.
d) FOR CURVED GIRDER BRIDGES WITH SKEWED SUPPORTS, GENERALLY PLACE INTERMEDIATE DIAPHRAGMS RADIAL TO THE
AND IN CONTIGUOUS LINES.
c) FOR CURVED GIRDER BRIDGES WITH RADIAL SUPPORTS, PLACE INTERMEDIATE AND PIER DIAPHRAGMS RADIAL TO THE GIRDERS
ORIENT CROSS FRAMES PARALLEL TO THE SKEW ANGLES OF 70° TO 90°, OR NORMAL TO THE GIRDER FOR SKEWS LESS THAN 70°.
THE GIRDERS FOR FUTURE BEARING REPLACEMENT IS INCORPORATED INTO THE DESIGN. IF PIER DIAPHRAGMS ARE USED,
ARE MADE TO TRANSMIT HORIZONTAL SUPERSTRUCTURE FORCES INTO THE BEARINGS, AND AN ACCEPTABLE METHOD FOR JACKING
b) FOR STRAIGHT BRIDGES, PIER DIAPHRAGMS (DIAPHRAGMS AT INTERMEDIATE BEARINGS ) MAY BE OMITTED IF PROVISIONS
(WITHOUT COMPROMISING THE BRACING OF GIRDERS ) TYPICALLY RESULTS IN A MORE ECONOMICAL DESIGN.
SKEWED, VERY WIDE BRIDGES (BRIDGES WITH A HIGH SKEW INDEX, I ), OMITTING SELECT DIAPHRAGMS
RESULTS IN LOWER DIAPHRAGM FORCES, BUT MAY INCREASE GIRDER FLANGE LATERAL BENDING MOMENTS. IN SEVERELY
IN CONTIGUOUS LINES OR IN A STAGGERED ARRANGEMENT. THE USE OF A STAGGERED ARRANGEMENT TYPICALLY
FOR SKEW ANGLES OF 70° TO 90°. FOR SKEWS LESS THAN 70°, PLACE DIAPHRAGMS NORMAL TO THE GIRDER, EITHER
a) FOR STRAIGHT BRIDGES, PLACE INTERMEDIATE DIAPHRAGMS PARALLEL TO THE SKEW AND IN CONTIGUOUS LINES
4. USAGE AND ORIENTATION OF DIAPHRAGMS
(THIS STANDARD IS ONLY APPLICABLE FOR BRIDGES DESIGNED WITH A REFINED METHOD OF ANALYSIS)
DIRECTOR, BUR. OF PROJECT DELIVERY
APR.29, 2016 APR.29, 2016
COMMONWEALTH OF PENNSYLVANIADEPARTMENT OF TRANSPORTATION
STANDARD
WITH REFINED METHODS OF ANALYSIS
CROSS FRAME AND SOLID PLATE
DIAPHRAGMS FOR STEEL BEAM/GIRDER
BRIDGES DESIGNED
BD-619M
SHEET 2 OF 5
CHIEF BRIDGE ENGINEER
RECOMMENDEDRECOMMENDED
NOTES FOR DESIGNING AND DETAILING DIAPHRAGMS (CONTINUED FROM SHEET 1)
BUREAU OF PROJECT DELIVERY
STRAIGHT GIRDER BRIDGES SHOULD BE CATEGORIZED BY SKEW INDEX. THE SKEW INDEX, "I " IS
CALCULATED AS FOLLOWS:
WHERE:
SG
S
S p
7. CHARACTERIZATION OF STRAIGHT BRIDGES BY SKEW INDEX
G
S
p
L = SPAN LENGTH (FT)
CURVED GIRDER BRIDGES CANNOT BE CHARACTERIZED BY SKEW INDEX AT THIS TIME.
W = BRIDGE WIDTH PERPENDICULAR TO THE CENTERLINE, FASCIA GIRDER TO FASCIA GIRDER (FT)
GUSSET PLATES.
AXIAL FORCE EFFECTS. THE FLANGES OF W SECTIONS MAY REQUIRE COPING TO ALLOW FOR CONNECTION TO
HIGH ORTHOGONAL FORCES (SUCH AS JACKING FORCES ) CAUSING BENDING OF THE MEMBER, OR UNUSUALLY HIGH
ESPECIALLY FOR END DIAPHRAGMS. JUSTIFICATION FOR THE USE OF W SECTIONS INCLUDES THE POTENTIAL FOR
W SECTIONS: IN SPECIAL CASES WIDE FLANGE W SECTIONS (AISC WIDE FLANGE, OR "W", SHAPES ) MAY BE USED,
OR "W" SHAPES ) IN HALF LONGITUDINALLY, WHICH ADDS SIGNIFICANT FABRICATION AND STRAIGHTENING COSTS.
(AISC "WT" SHAPES ) MAY BE USED. WT SECTIONS ARE FABRICATED BY CUTTING W SECTIONS (AISC WIDE FLANGE,
WT SECTIONS: WHEN DESIGN FORCE EFFECTS EXCEED THE CAPACITY OF ANGLE SECTIONS, WT SECTIONS
SPECIAL COATINGS AND SOME REVERSE-SIDE WELDING ARE TYPICALLY REQUIRED.
DOUBLE ANGLES ARE GENERALLY MORE EXPENSIVE TO FABRICATE THAN WT SECTIONS SINCE MORE HANDLING,
(AISC "L" SHAPES ). EQUAL LEG ANGLES SHOULD BE USED. UNEQUAL LEG ANGLES SHOULD NOT BE USED.
ANGLE SECTIONS: THE MOST ECONOMICAL DIAPHRAGM MEMBERS ARE TYPICALLY SINGLE ANGLE SECTIONS
ARE LISTED BELOW.
THE MOST COMMON TYPES OF DIAPHRAGM MEMBERS FOR TYPE X, TYPE K AND TYPE K INVERTED DIAPHRAGMS
DIAPHRAGMS HAVE SIGNIFICANTLY HIGHER DESIGN LOADS THAN OTHER DIAPHRAGMS IN THE SAME BRIDGE.
GIVEN DESIGN, BUT IT IS ACCEPTABLE TO USE DIFFERENT MEMBER SIZES IN CASES WHERE A LIMITED NUMBER OF
IT IS GENERALLY DESIRABLE TO REASONABLY MINIMIZE THE NUMBER OF DIFFERENT TYPES OF MEMBERS USED IN A
SELECT THE MOST ECONOMICAL DIAPHRAGM MEMBERS WHICH MEET DESIGN STRENGTH AND DETAILING REQUIREMENTS.
6. SELECTION OF DIAPHRAGM MEMBERS
TO JACKING LOADS FOR BEARING REPLACEMENT, THE NEED FOR JACKING STIFFENERS SHOULD BE INVESTIGATED.
FOR CONNECTION TO STIFFENERS IF GUSSET PLATES ARE NOT USED. IF WELDED PLATE GIRDERS WILL BE SUBJECT
AN ECONOMICAL W SECTION IS NOT AVAILABLE. THE FLANGES OF PLATE GIRDERS MAY REQUIRE COPING TO ALLOW
WELDED PLATE GIRDERS: WELDED PLATE GIRDERS MAY BE USED FOR SOLID PLATE DIAPHRAGMS IN CASES WHERE
DIAPHRAGM APPLICATIONS AND HIGH COST/LIMITED AVAILABILITY.
ARE NOT USED. THE USE OF EXCESSIVELY HEAVY W SECTIONS IS DISCOURAGED DUE TO POOR ECONOMY IN
THE FLANGES OF W SECTIONS MAY REQUIRE COPING TO ALLOW FOR CONNECTION TO STIFFENERS IF GUSSET PLATES
CASES WHERE A CHANNEL SECTION OF THE REQUIRED SIZE IS NOT AVAILABLE (SUCH AS CASES OF DEEPER GIRDERS ).
W SECTIONS: W SECTIONS (AISC WIDE FLANGE, OR "W", SHAPES ) MAY BE USED FOR SOLID PLATE DIAPHRAGMS IN
AND WIDELY AVAILABLE CHANNEL SECTION IS NOT AVAILABLE IN THE REQUIRED SIZE.
DEPTH. BENT PLATES MAY BE MORE ECONOMICAL THAN CHANNEL SECTIONS IN CASES WHERE A COMMONLY ROLLED
BENT PLATES: COLD BENT PLATES MAY BE USED FOR SOLID PLATE DIAPHRAGMS IN CASES OF SHALLOW GIRDER
COMMONLY ROLLED AND WIDELY AVAILABLE SIZE IS USED.
IN CASES OF SHALLOW GIRDER DEPTH. CHANNEL SECTIONS ARE TYPICALLY REASONABLY ECONOMICAL IF A
CHANNEL SECTIONS: CHANNEL SECTIONS (AISC "C" AND "MC" SHAPES ) MAY BE USED FOR SOLID PLATE DIAPHRAGMS
THE MOST COMMON TYPES OF DIAPHRAGM MEMBERS FOR SOLID PLATE DIAPHRAGMS ARE LISTED BELOW.
IN CASES OF MULTIPLE SPAN UNITS, THE LARGEST SKEW INDEX OF ALL THE SPANS SHALL BE USED TO CHARACTERIZE THE UNIT.
S
REMOVAL EXCEED THE LIMITATIONS OF A TYPE K INVERTED DIAPHRAGM.
DIAPHRAGM FORCE EFFECTS FROM A REFINED ANALYSIS AND/OR IN CASES WHERE JACKING FORCES FOR BEARING
SOLID PLATE: SOLID PLATE DIAPHRAGMS SHOULD BE USED IN CASES WHERE NECESSARY TO ADDRESS HIGH
THE USE OF TYPE K INVERTED DIAPHRAGMS FACILITATES PASSAGE OF LARGER UTILITIES THROUGH THE DIAPHRAGM.
REMOVAL OCCURS AT THE END DIAPHRAGM AND JACKING LOADS DO NOT REQUIRE A SOLID PLATE DIAPHRAGM.
TYPE K INVERTED: TYPE K INVERTED DIAPHRAGMS SHOULD BE USED IN CASES WHERE JACKING FOR BEARING
WHERE GIRDER JACKING FOR BEARING REMOVAL IS PROVIDED AT A LOCATION OTHER THAN THE END DIAPHRAGM.
TYPE K: TYPE K DIAPHRAGMS ARE TYPICALLY THE MOST ECONOMICAL DESIGN AND SHOULD BE USED IN CASES
END DIAPHRAGMS
5. SELECTION OF DIAPHRAGM TYPE (CONTINUED FROM SHEET 1 )
f
FROM THE DECK TO THE BEARINGS.
AND END DIAPHRAGMS, THE PIER AND END DIAPHRAGMS SHOULD BE DESIGNED TO TRANSFER THE RESULTING WIND LOAD
THE RESULTING WIND LOAD IN THE DECK CAN BE ASSUMED TO BE TRANSFERRED BY AND THROUGH THE DECK TO THE PIER
TRIBUTARY SPAN ASSUMPTION. THE DIAPHRAGMS SHOULD BE DESIGNED TO TRANSFER THIS LOAD INTO THE DECK.
BY MEANS OF FLANGE LATERAL BENDING. THE LOAD IN EACH INTERMEDIATE DIAPHRAGM CAN BE DETERMINED BY MEANS OF A
THE BOTTOM FLANGE CAN BE ASSUMED TO TRANSFER THE RESULTING WIND LOAD TO INDIVIDUAL INTERMEDIATE DIAPRAGMS
WIND PRESSURE ON THE BOTTOM 50% OF THE DEPTH OF FASCIA GIRDER CAN BE APPORTIONED TO THE BOTTOM FLANGE.
ASSUMED TO BE TRANSFERRED DIRECTLY INTO THE DECK.
WIND PRESSURE ON TOP 50% OF THE DEPTH OF THE FASCIA GIRDER CAN BE APPORTIONED TO THE TOP FLANGE AND CAN BE
LRFD. WIND PRESSURE APPLIED TO THE FASCIA GIRDER CAN BE APPORTIONED AS FOLLOWS:
PRESSURES AND ASSOCIATED FACTORS SHOULD BE CALCULATED FOLLOWING THE GUIDANCE IN SECTION 3 OF THE AASHTO
WIND LOAD EFFECTS SHOULD BE INCLUDED IN THE CALCULATION OF DIAPHRAGM DESIGN FORCES. APPROPRIATE WIND
c) WIND LOAD EFFECTS:
GRAVITY LOAD EFFECTS SHOULD BE DETERMINED FROM THE REFINED ANALYSIS.
FOR BRIDGES WITH SKEW INDEX GREATER THAN 0.30 (I 0.30 ) WHERE REFINED ANALYSIS METHODS ARE USED, DIAPHRAGM
GRAVITY LOADS MAY BE NEGLECTED WHEN DETERMINING DIAPHRAGM DESIGN LOADS.
FOR BRIDGES WITH SKEW INDEX LESS THAN 0.30 (I 0.30 ) WHERE SIMPLIFIED ANALYSIS METHODS ARE USED, THE EFFECTS OF
b) GRAVITY LOAD (DEAD LOAD AND LIVE LOAD) EFFECTS:
I = W / { L TAN ( ) }
f
S
S
NOTES FOR DESIGNING AND DETAILING DIAPHRAGMS, CONTINUED ON SHEET 3* *
obb
2
effb fbr
2
f
2
eff bb
2
TB
A LINE PARALLEL TO THE CENTERLINE OF THE SUPPORT (90 DEGREES = NONSKEWED ).
= THE SMALLER ANGLE BETWEEN THE HIGHWAY CENTERLINE (OR A TANGENT THERETO) AND
PRESENTED IN SECTION 3 OF THE AASHTO LRFD, WITH THE FOLLOWING ADDITIONS:
PART OF THE DIAPHRAGM DESIGN. LOAD FACTORS FOR THE LOAD COMBINATIONS FOR EACH LIMIT STATE SHALL BE AS
ALL APPLICABLE LIMIT STATES, AS IDENTIFIED IN SECTION 3 OF THE AASHTO LRFD, SHALL BE INVESTIGATED AS
a) LIMIT STATES AND LOAD FACTORS:
9. DETERMINATION OF DESIGN LOADS
DM-4 SECTION 4.6.1.2.1.
REFINED ANALYSIS IS REQUIRED FOR KINKED GIRDER BRIDGES MEETING THE DEFINITION OF CURVED GIRDERS AS OUTLINED IN
REFINED ANALYSIS IS REQUIRED FOR ALL CURVED GIRDER BRIDGES.
SKEW ANGLE 70 DEGREES.
REFINED ANALYSIS IS GENERALLY REQUIRED FOR STRAIGHT GIRDER BRIDGES WITH SKEW INDEX GREATER THAN 0.30 (I 0.30 ) AND
(TIMOSHENKO BEAM ) AND IN ACCORDANCE WITH THE REFINED ANALYSIS REQUIREMENTS OF DM-4 SECTION 4.6.3
ii. A COMPLETE REPRESENTATION OF THE STIFFNESS OF DIAPHRAGMS BY MEANS OF A SHEAR-DEFORMABLE BEAM ELEMENT
i. CONSIDERATION OF WARPING STIFFNESS WHEN MODELING THE TORSIONAL STIFFNESS OF I-SHAPED GIRDERS.
THE 2D ANALYSIS INCLUDES BOTH OF THE FOLLOWING FEATURES:
a) REFINED ANALYSIS: REFINED ANALYSIS TYPICALLY CONSISTS OF 3D ANALYSIS, OR MAY CONSIST OF AN ENHANCED 2D ANALYSIS IF
8. LEVEL OF REFINED ANALYSIS
f
DIRECTOR, BUR. OF PROJECT DELIVERY
EFFECTS IN THE APPROPRIATE LIMIT STATES WHEN EVALUATING BRACING STRENGTH AND STIFFNESS REQUIREMENTS.
MOMENT (M ) VALUES, THEY SHOULD BE MULTIPLIED BY A 1.0 LOAD FACTOR FOR COMBINATION WITH OTHER FORCE
ONCE THE STABILITY BRACING FORCES HAVE BEEN CALCULATED USING THESE APPROPRIATELY FACTORED ULTIMATE
ANY APPLICABLE UTILITY LOADS, BUT NOT FUTURE WEARING SURFACE LOADING.
IN THE ABOVE-LISTED LIMIT STATES, FOR CONSTRUCTION CONDITION LIMIT STATE CHECKS, DW SHOULD ONLY INCLUDE
CHECKED FOR DECK PLACEMENT CONDITIONS (THE STRENGTH I LIMIT STATE COVERS THIS CONDITION ).
MATERIALS WITH NO CONSTRUCTION LIVE LOAD ). THE STRENGTH III, CONSTRUCTION CONDITION, NEED NOT BE
WIND LOADING AND REDUCED CONSTRUCTION LOADS (SUCH AS WEIGHT OF STATIC CONSTRUCTION EQUIPMENT AND STORED
IN THE ABOVE-LISTED LIMIT STATES, THE STRENGTH III, CONSTRUCTION CONDITION, LIMIT STATE SHOULD INCLUDE
OF CONSTRUCTION LIVE LOADS AND DYNAMIC EFFECTS AS APPLICABLE.
NO WIND LOADING, BUT FULL CONSTRUCTION LOADS ASSOCIATED WITH DECK PLACEMENT, INCLUDING CONSIDERATION
IN THE ABOVE-LISTED LIMIT STATES, THE STRENGTH I, CONSTRUCTION CONDITION, LIMIT STATE SHOULD INCLUDE
EFFECTS IF APPLICABLE )
SPECIAL STEEL CONSTRUCTION LIMIT STATE: 1.4 DC + 1.4 CONSTRUCTION LOADS (INCLUDING DYNAMIC
0.4 WS + 1.0 WL
STRENGTH V, FINAL CONDITION, COMPOSITE, NEGATIVE MOMENT REGIONS: 1.25 DC + 1.5 DW + 1.35 LL +
1.25 DW + 1.4 WS +1.25 CONSTRUCTION LOADS (DC IS DEAD LOAD OF STEEL ONLY)
STRENGTH III, CONSTRUCTION CONDITION, NONCOMPOSITE, POSITIVE OR NEGATIVE MOMENT REGIONS: 1.25 DC +
STRENGTH III, FINAL CONDITION, COMPOSITE, NEGATIVE MOMENT REGIONS: 1.25 DC + 1.5 DW + 0 LL + 1.4 WS
1.25 DW + 1.5 CONSTRUCTION LOADS (INCLUDING DYNAMIC EFFECTS IF APPLICABLE )
STRENGTH I, CONSTRUCTION CONDITION, NONCOMPOSITE, POSITIVE OR NEGATIVE MOMENT REGIONS: 1.25 DC +
STRENGTH I, FINAL CONDITION, COMPOSITE, NEGATIVE MOMENT REGIONS: 1.25 DC + 1.5 DW + 1.75 LL
SHOULD BE BASED ON THE FOLLOWING LOAD COMBINATIONS FOR THE GIVEN LIMIT STATE UNDER INVESTIGATION:
(IN ACCORDANCE WITH THE PROVISIONS OF THE AISC SPEC APPENDIX 6.3 AND/OR THE FHWA SBDH VOL. 13 )
THE ULTIMATE MOMENT (M ) USED TO CALCULATE STABILITY BRACING STRENGTH AND STIFFNESS REQUIREMENTS
DEFINITION OF THE ULTIMATE MOMENT (M ).
SEE PENNDOT DM-4, APPENDIX E6P, SECTION E6.5P FOR BASIC DEFINITION OF ALL VARIABLES. SEE BELOW FOR ADDITIONAL
M = ( 0.005 L L M ) / ( n E I C h )
THE STRENGTH REQUIREMENT (AS PRESENTED IN THE FHWA SBDH, VOL. 13 ) IS:
= ( 2.4 L M ) / ( 0 n E I C )
THE STIFFNESS REQUIREMENT (AS PRESENTED IN THE FHWA SBDH, VOL. 13 ) IS:
AND/OR THE FHWA SBDH, VOL. 13 ) MUST BE SATISFIED.
BOTH THE STRENGTH AND STIFFNESS REQUIREMENTS FOR STABILITY BRACING (AS SPECIFIED IN THE AISC SPEC APPENDIX 6.3
APR.29, 2016 APR.29, 2016
COMMONWEALTH OF PENNSYLVANIADEPARTMENT OF TRANSPORTATION
STANDARD
WITH REFINED METHODS OF ANALYSIS
CROSS FRAME AND SOLID PLATE
DIAPHRAGMS FOR STEEL BEAM/GIRDER
BRIDGES DESIGNED
BD-619M
SHEET 3 OF 5
CHIEF BRIDGE ENGINEER
RECOMMENDEDRECOMMENDED
BUREAU OF PROJECT DELIVERY
10. DETAILED DESIGN PROCEDURES FOR TYPE X AND TYPE K INTERMEDIATE DIAPHRAGMS
TO THE ECCENTRICITY OF CONNECTIONS (BEAM-COLUMN INTERACTION), AND SHALL CONSIDER SECOND-ORDER MOMENT
FATIGUE DESIGN: EVALUATE FATIGUE OF THE BASE METAL IN THE CONNECTION OF DIAPHRAGM MEMBERS TO GUSSET PLATES USING
b) DESIGN OF GUSSET PLATES
c) DESIGN OF WELDED CONNECTION OF DIAPHRAGM MEMBERS TO GUSSET PLATES
d) DESIGN OF BOLTED CONNECTION OF GUSSET PLATES TO CONNECTION PLATES AND/OR BEARING STIFFENERS
ALL APPLICABLE COMBINATIONS OF TENSION AND COMPRESSION LOADS IN INDIVIDUAL MEMBERS SHOULD BE CONSIDERED;
EITHER INVESTIGATE ALL TRUE CONCURRENT COMBINATIONS OF LOADS, OR DESIGN FOR CONSERVATIVE ENVELOPING
COMBINATIONS OF THE MAXIMUM COMPRESSION AND TENSION FORCES IN EACH MEMBER CONNECTED TO THE GUSSET PLATE.
INVESTIGATE SHEAR IN THE BOLTS AND BEARING IN THE CONNECTED MATERIALS (BOTH THE GUSSET PLATE AND THE
CONNECTION PLATE OR BEARING STIFFENER) UNDER ALL APPLICABLE STRENGTH LIMIT STATES. INVESTIGATE SLIP OF
BOLTED CONNECTIONS UNDER THE SERVICE II LIMIT STATE.
USE ‡" DIAMETER ASTM A325 BOLTS WHENEVER POSSIBLE. 1" DIAMETER ASTM A325 BOLTS MAY BE USED IN SITUATIONS
WHERE THE USE OF ‡" DIAMETER BOLTS WOULD RESULT IN AN EXCESSIVE NUMBER OF BOLTS IN THE CONNECTION. THE
USE OF ASTM A325 BOLTS LARGER THAN 1" DIAMETER, OR THE USE OF ANY SIZE ASTM A490 BOLTS, REQUIRES APPROVAL
FROM THE CHIEF BRIDGE ENGINEER.
DESIGN BOLTED CONNECTIONS ASSUMING A CLASS B CONSTANT SURFACE SLIP RESISTANCE.
NOTES FOR DESIGNING AND DETAILING DIAPHRAGMS (CONTINUED FROM SHEET 2)
S
S
AMPLIFICATION IN THE CASE OF COMPRESSION LOADING IN ACCORDANCE WITH THE AASHTO LRFD (SECTION 6.9.2.2 ).
AASHTO LRFD (SECTION 6.9.4.4 ) SHALL BE USED. FOR OTHER SECTIONS SUCH AS WT, W, AND CHANNEL SECTIONS
PROVISIONS (SECTION 6 ). FOR ANGLE SECTIONS (AISC "L" SHAPES ) THE EFFECTIVE SLENDERNESS RATIO METHOD IN THE
STRENGTH DESIGN: STRENGTH DESIGN SHALL BE PERFORMED IN ACCORDANCE WITH THE APPROPRIATE AASHTO LRFD
(AISC "WT", "WIDE FLANGE", "C", AND "MC" SHAPES ), THE DESIGN SHALL CONSIDER BOTH AXIAL LOAD AND FLEXURE DUE
THE EFFECTIVE LENGTH OF TOP CHORD, BOTTOM CHORD AND DIAGONAL MEMBERS SHALL BE DETERMINED IN ACCORDANCE WITH THE
APPLICABLE PROVISIONS OF THE AASHTO LRFD. FOR DIAGONAL MEMBERS IN TYPE X DIAPHRAGMS WHICH ARE CONNECTED AT THEIR
EFFECTIVE LENGTH CALCULATIONS.
POINTS OF INTERSECTION, SEE SECTION 2.7 OF THE FHWA SBDH, VOL. 13, FOR PROVISIONS REGARDING THE USE OF 0.5L IN
LONGITUDINAL WELDS AS A CATEGORY E DETAIL, AS SPECIFIED IN THE AASHTO LRFD (TABLE 6.6.1.2.3.-1 ). FOR INTERSTATE
AND NATIONAL HIGHWAY SYSTEM (NHS) BRIDGES, DESIGN DIAPHRAGMS FOR THE FATIGUE I LIMIT STATE AS DEFINED IN THE AASHTO
FOR A 100-YEAR SERVICE LIFE.
LRFD. FOR OTHER BRIDGES, DESIGN DIAPHRAGMS FOR THE FATIGUE II LIMIT STATE AS DEFINED IN THE AASHTO LRFD; DESIGNED
STRENGTH OF THE WELDED CONNECTIONS IN ACCORDANCE WITH THE PROVISIONS OF THE AASHTO LRFD (SECTION 6 ).
DESIGNED WITH ADEQUATE STRENGTH TO TRANSMIT THE DIAPHRAGM FORCES INTO THE GIRDERS. INVESTIGATE THE
THE WELDS CONNECTING THE CONNECTION PLATE (OR BEARING STIFFENER ) TO THE GIRDER WEB AND FLANGES SHOULD BE
e) DESIGN OF CONNECTION PLATES
THE BOLTED CONNECTIONS OF GUSSET PLATES TO CONNECTION PLATES AND/OR BEARING STIFFENERS SHOULD BE DESIGNED
IN ACCORDANCE WITH THE PROVISIONS OF THE AASHTO LRFD (SECTION 6 ). IN-PLANE ECCENTRICITY OF LOADING APPLIED
TO THE BOLT GROUP (RESULTANT OF LOAD NOT ACTING THROUGH THE CENTRIOD OF THE BOLT GROUP ) SHALL BE CONSIDERED.
SHOULD BE DESIGNED IN ACCORDANCE WITH THE PROVISIONS OF THE AASHTO LRFD (SECTION 6 ).
THE WELDED CONNECTION OF DIAPHRAGM MEMBERS (TOP CHORD, BOTTOM CHORD, DIAGONALS ) TO THE GUSSET PLATES
GUSSET PLATES SHALL BE DESIGNED IN ACCORDANCE WITH THE APPROPRIATE PROVISIONS OF THE AASHTO LRFD (SECTION 6,
INCLUDING SECTIONS 6.13.4 AND 6.13.5 ), ADDRESSING TENSION, COMPRESSION AND SHEAR AS APPLICABLE.
REGION SHOULD BE USED FOR CALCULATION OF STABILITY BRACING FORCES IN THAT PARTICULAR REGION.
IF DIAPHRAGM SPACING IS DIFFERENT IN THE POSITIVE AND NEGATIVE MOMENT REGIONS, THE DIAPHRAGM SPACING IN EACH
DIAPHRAGM AWAY FROM THE PIER SHOULD BE USED TO CALCULATE STABILITY BRACING FORCES.
REGIONS (IN MULTIPLE SPAN CONTINUOUS BRIDGES ). THE ULTIMATE NEGATIVE MOMENT AT THE LOCATION OF THE FIRST
STABILITY BRACING FORCES SHOULD BE CALCULATED FOR DIAPHRAGMS BRACING BOTTOM FLANGES IN NEGATIVE MOMENT
REGION; ONCE THE DECK IS CURED, THE TOP FLANGE IN COMPRESSION IS CONTINUOUSLY BRACED BY THE DECK.
EFFECTS SHOULD BE CONSIDERED IN CALCULATING STABILITY BRACING FORCES FOR DIAPHRAGMS IN THE POSITIVE MOMENT
MOMENT LOCATION ) SHOULD BE USED TO CALCULATE STABILITY BRACING FORCES. ONLY NON-COMPOSITE DEAD LOAD
REGIONS. THE MAXIMUM POSITIVE MOMENT AND ASSOCIATED DIAPHRAGM SPACING (IN THE VICINITY OF THE MAXIMUM POSITIVE
STABILITY BRACING FORCES SHOULD BE CALCULATED FOR DIAPHRAGMS BRACING TOP FLANGES IN POSITIVE MOMENT
SPECIFIED ABOVE IN THIS STANDARD.
(APPENDIX 6.3 ) AND THE FHWA SBDH (VOL 13 ). STABILITY BRACING FORCES SHOULD BE COMBINED WITH OTHER LOADS AS
STABILITY BRACING STRENGTH AND STIFFNESS REQUIREMENTS SHOULD BE SATISFIED, IN ACCORDANCE WITH THE AISC SPEC
e) STABILITY BRACING FORCES:
STRESS RANGES WHEN COMPUTED USING A REFINED ANALYSIS.
GUIDANCE PROVIDED IN THE COMMENTARY OF THE AASHTO LRFD (C6.6.1.2.1 ), REGARDING THE DETERMINATION OF FATIGUE
REQUIRED AND SHALL INCLUDE DETERMINATION OF FATIGUE STRESS RANGES IN THE DIAPHRAGM MEMBERS. FOLLOW THE
FOR CURVED GIRDER BRIDGES OR BRIDGES WITH A SKEW INDEX GREATER THAN 0.30 (I 0.30 ) A REFINED ANALYSIS IS
THE MINIMUM WELD SIZE REQUIREMENTS OF THE AASHTO LRFD SHALL BE MET.
FILLET WELDS CONNECTING DIAPHRAGM CHORD AND DIAGONAL MEMBERS TO GUSSET PLATES SHALL NOT BE LESS THAN 4".
INDEX LESS THAN 0.30 (I 0.30 ) WHERE A REFINED ANALYSIS IS NOT PERFORMED. INSTEAD THE LENGTH OF LONGITUDINAL
A DETAILED ANALYSIS OF FATIGUE LOADING IS NOT REQUIRED FOR THE DESIGN OF DIAPHRAGMS IN BRIDGES WITH A SKEW
d) FATIGUE LOADING EFFECTS:
9. DETERMINATION OF DESIGN LOADS (CONTINUED FROM SHEET 2 )
BOLT SPACINGS, END DISTANCES, AND EDGE DISTANCES SHOULD MEET AASHTO LRFD REQUIREMENTS.
a) DESIGN OF TOP CHORD, BOTTOM CHORD, AND DIAGONALS IN TYPE X AND TYPE K DIAPHRAGMS.
DIRECTOR, BUR. OF PROJECT DELIVERY
MONTHS OR MORE FOLLOWING THE INTITIAL CLEANING. {INCLUDE THIS NOTE FOR WEATHERING STEEL BRIDGES ONLY }
PUBLICATION 408 SECTION 1060.3(b)3. REBLAST UNPAINTED ELEMENTS THAT REMAIN UNASSEMBLED FOR A PERIOD OF 12
f) BLAST CLEAN THE FAYING SURFACES OF SPLICES AND CONNECTIONS OF ALL STRUCTURAL ELEMENTS IN ACCORDANCE WITH
{INCLUDE THIS NOTE FOR PAINTED BRIDGES AND WEATHERING STEEL BRIDGES }
FURNISH PAINT THAT HAS BEEN QUALIFIED AS CLASS B IN ACCORDANCE WITH SECTION 6.13.2.8 OF AASHTO LRFD SPECIFICATION. e)
CONNECTED PARTS (SHEAR PLANE ).
AN UNTHREADED SHANK OF SUFFICIENT LENGTH TO NOT ALLOW ANY THREADS TO EXIST IN THE PLANE BETWEEN THE TWO
USE {INDICATE 7/8" OR AS SPECIFIED IN THE DESIGN AND PLANS } DIAMETER ASTM DESIGNATION A325 BOLTS HAVING d)
USE STANDARD SIZE HOLES FOR ALL BOLTS. c)
STEEL DEAD LOAD FIT (SDLF ) OR TOTAL DEAD LOAD FIT (TDLF ) } CONDITION.
APPROPRIATE LOADING CONDITION, AS INDICATED IN NOTE 3.a OF THIS STANDARD, I.E., NO LOAD FIT (NLF ),
DEVELOP SHOP DRAWINGS AND ERECTION PROCEDURES THAT DETAIL ALL WEBS VERTICAL UNDER {SPECIFY THE b)
PROVIDE MATERIALS AND WORKMANSHIP IN ACCORDANCE WITH PUBLICATION 408 AND AASHTO/AWS D1.5 SPECIFICATIONS. a)
14. NOTES TO BE SHOWN ON THE CONSTRUCTION DRAWINGS
THE GOAL OF ACHIEVING A BALANCE OF ECONOMY, CONSTRUCTABILITY, AND LONG TERM SERVICEABILITY CRITERIA.
CONSTRUCTION (I.E., THE SUPPORT OF GIRDERS ON TEMPORARY BLOCKING ). BASE BEARING DESIGN DECISIONS ON
PLATES BEVELED BOTH TRANSVERSELY AND LONGITUDINALLY, OR REQUIRING THE BLOCKING OF GIRDERS DURING
CONDITIONS (DURING ALL STAGES OF CONSTRUCTION AND UNDER FINAL CONDITIONS ), CONSIDER THE USE OF SOLE
IF BEARINGS CANNOT BE ECONOMICALLY DESIGNED TO ACCOMMODATE ALL ROTATIONAL DEMANDS UNDER ALL LOADING d)
ERECTION, WITH ALL STEEL ERECTED PRIOR TO DECK PLACEMENT, AFTER DECK PLACEMENT, ETC.).
MAGNITUDE AND DIRECTION OF GIRDER LAYOVER AT VARIOUS STAGES OF CONSTRUCTION (I.E., DURING GIRDER
ON THE VALUES OF THE GIRDER LAYOVER ROTATIONAL DEMANDS. THE CHOSEN DETAILING METHOD AFFECTS THE
OR STRAIGHT GIRDER BRIDGES ), CONSIDER THE EFFECTS OF THE CHOSEN DETAILING METHOD (NLF, SDLF, TDLF )
WHEN EVALUATING GIRDER LAYOVER ROTATIONAL DEMANDS ON BEARINGS AT SKEWED SUPPORTS (FOR EITHER CURVED c)
OF THE GIRDER ) AND GIRDER LAYOVER (ROTATION ABOUT THE LONGITUDINAL AXIS OF THE GIRDER ).
CONSIDER BOTH THE MAJOR AXIS BENDING ROTATION OF THE GIRDER (ROTATION ABOUT THE TRANSVERSE AXIS
b) WHEN EVALUATING THE ROTATIONAL DEMAND ON BEARINGS FOR CURVED OR SKEWED STEEL GIRDER BRIDGES,
AND UNDER FINAL CONDITIONS.
COMBINATIONS OF THESE DEMANDS AT EACH STAGE OF CONSTRUCTION (INCLUDING PRIOR TO DECK PLACEMENT)
HORIZONTAL MOVEMENT DEMANDS, AND ROTATIONAL DEMANDS, AS APPROPRIATE. CONSIDER THE CONCURRENT
DESIGN BEARINGS TO ACCOMMODATE APPLICABLE VERTICAL LOAD DEMANDS, HORIZONTAL LOAD DEMANDS, a)
13. BEARING DESIGN
DEFORMATIONS MUST BE CONSIDERED WHEN EVALUATING THE STRENGTH ADEQUACY OF THE DIAPHRAGM.
IN SITUATIONS WHERE THE SPAN TO DEPTH RATIO OF SOLID PLATE DIAPHRAGMS IS LESS THAN OR EQUAL TO 4.0, SHEAR d)
BOLTED CONNECTIONS UNDER THE SERVICE II LIMIT STATE.
CONNECTION PLATE OR BEARING STIFFENER ) UNDER ALL APPLICABLE STRENGTH LIMIT STATES. INVESTIGATE SLIP OF
SHEAR IN THE BOLTS AND BEARING IN THE CONNECTED MATERIALS (BOTH THE SOLID PLATE DIAPHRAGM'S WEB AND THE
LRFD (SECTION 6 ). ECCENTRICITY OF LOADING APPLIED TO THE BOLT GROUP SHALL BE CONSIDERED. INVESTIGATE
CONNECTIONS. THESE BOLTED CONNECTIONS SHOULD BE DESIGNED IN ACCORDANCE WITH THE PROVISIONS OF THE AASHTO
SOLID PLATE INTERMEDIATE OR PIER AND END DIAPHRAGMS ARE TYPICALLY CONNECTED TO STIFFENERS VIA BOLTED c)
THE APPROPRIATE PROVISIONS OF THE AASHTO LRFD (SECTION 6 ).
UNSTIFFENED WEB HAS SUFFICIENT AXIAL (BUCKLING ), WEB LOCAL YIELDING, AND WEB CRIPPLING CAPACITY, FOLLOWING
STIFFENERS SHOULD BE DESIGNED AND PROVIDED, UNLESS IT CAN BE CLEARLY SHOWN BY CALCULATION THAT THE
IF SOLID PLATE PIER OR END DIAPHRAGMS WILL BE SUBJECTED TO JACKING LOADS FOR BEARING REPLACEMENT, BEARING b)
AASHTO LRFD (SECTION 6 ).
LOAD EFFECTS IN A MANNER SIMILAR TO THE DESIGN OF OTHER STEEL GIRDERS OR BEAMS, IN ACCORDANCE WITH THE
TYPICALLY, SOLID PLATE INTERMEDIATE DIAPHRAGMS ARE DESIGNED FOR THEIR APPROPRIATE STRENGTH LIMIT STATE DESIGN a)
12. DETAILED DESIGN PROCEDURES FOR SOLID PLATE INTERMEDIATE OR PIER AND END DIAPHRAGMS
AASHTO LRFD (SECTIONS 6.9.2.1, 6.10.11.2 AND 6.13.3.2 ).
BE DESIGNED FOR BOTH DIAPHRAGM LOADS AND BEARING REACTIONS, FOLLOWING THE APPROPRIATE PROVISIONS OF THE
THE CONNECTION PLATES FOR PIER AND END DIAPHRAGMS TYPICALLY ALSO FUNCTION AS BEARING STIFFENERS AND SHOULD e)
WIND FORCE EFFECTS.
ACTION AS A BEAM STIFFENING AND STRENGTHENING THE EDGE OF THE DECK AT EXPANSION JOINTS, IN ADDITION TO ANY
THE DIAGONALS SHOULD BE DESIGNED TO CARRY DEAD LOAD AND LIVE LOAD REACTIONS FROM THE DIAPHRAGM TOP CHORD'S d)
AT THE POINT OF CONNECTION TO THE DIAGONALS ).
SUPPORTED AT ITS ENDS ANDOVER THE POINT OF CONNECTION TO THE DIAGONALS ), OR AS TWO SIMPLE SPANS (SIMPLY
EITHER A TWO SPAN CONTINUOUS BEAM (SIMPLY SUPPORTED AT ITS ENDS, CONTINUOUSTOP CHORD MAY BE TREATED AS
DECK AS WELL AS WHEEL LOADS APPLIED TO THE DECK, IN ADDITION TO ANY WIND FORCE EFFECTS. THE DIAPHRAGM
THE DIAPHRAGM TOP CHORD SHOULD BE DESIGNED TO CARRY A PORTION OF THE DEAD LOAD OF THE WET CONCRETE c)
THE USE OF OVERSIZE HOLES OR SLOTTED HOLES REQUIRES APPROVAL FROM THE CHIEF BRIDGE ENGINEER.
HOLE SHALL BE THE NOMINAL DIAMETER OF THE BOLT PLUS „".
NOMINAL DIAMETER OF THE BOLT PLUS ˆ". FOR BOLTS 1" IN DIAMETER AND LARGER, THE WIDTH OF EACH STANDARD
USE STANDARD SIZE HOLES. THE STANDARD HOLE DIAMETER FOR BOLTS SMALLER THAN 1" IN DIAMETER SHALL BE THE
DIRECTION OF THE APPLIED BEARING FORCE SHALL BE CHECKED.
CLEAR DISTANCE BETWEEN BOLT HOLES OR BETWEEN THE BOLT HOLE AND THE END OF THE MEMBER IN THE
TYPICALLY MADE TO ACT IN A COMPOSITE FASHION WITH THE DECK VIA THE USE OF SHEAR CONNECTORS.
W SECTION (AISC "C", "MC", OR WIDE FLANGE SHAPE ). THE DIAPHRAGM TOP CHORD IN THIS SITUATION IS
STIFFEN THE EDGE OF THE DECK AT EXPANSION JOINTS, THE DIAPHRAGM TOP CHORD IS TYPICALLY A CHANNEL OR
b) IN SITUATIONS WHERE TYPE K INVERTED END DIAPHRAGMS ARE USED AND THE TOP CHORD ACTS TO STRENGTHEN AND
SPECIFICALLY MODIFIED BELOW.
NOTE 10 OF THIS STANDARD FOR DESIGN OF TYPE X AND TYPE K INTERMEDIATE DIAPHRAGMS, EXCEPT AS
a) IN GENERAL, DESIGN TYPE K AND TYPE K INVERTED END DIAPHRAGMS FOLLOWING THE GUIDANCE PRESENTED IN
11. DETAILED DESIGN PROCEDURES FOR TYPE K AND TYPE K INVERTED PIER AND END DIAPHRAGMS
APR.29, 2016 APR.29, 2016
COMMONWEALTH OF PENNSYLVANIADEPARTMENT OF TRANSPORTATION
*
(TYP.)
TYPE K
(TYP.)
(TYP.)
TYPE K INVERTED
JACKING LOCATIONS
(TYP.)
(TYP.)
(TYP.)
(TYP.)
(TYP.)
STANDARD
WITH REFINED METHODS OF ANALYSIS
CROSS FRAME AND SOLID PLATE
DIAPHRAGMS FOR STEEL BEAM/GIRDER
BRIDGES DESIGNEDSOLID PLATE
BD-619M
(TYP.)
AS REQ'D. BY DESIGN
(TYP.)
(SEE NOTE 2)
ANGLE OR WT (TYP.)
(TYP.)
BY DESIGN
AS REQ'D.
BY DESIGN (TYP.)
SIZE AS REQ'D.
CONNECTION PLATE
REQ'D. BY DESIGN
W-SECTION SIZE AS
(TYP.)
BY DESIGN
AS REQ'D.
SHEET 4 OF 5
CHIEF BRIDGE ENGINEER
RECOMMENDEDRECOMMENDED
NOTES:
1" MIN.
1" MIN.
ACCEPTABLE BY DESIGN.
ALSO BE USED. IF SHOWN
MIDSPAN OF THE DIAPHRAGM MAY
A SINGLE JACKING POINT AT THE
END DIAPHRAGMS
BUREAU OF PROJECT DELIVERY
(TYP.)
(TYP.)
BY DESIGN
AS REQ'D.
TYPE X
(TYP.)
(TYP.)
30° MIN.
FILL LP
SEE DETAIL A
BOLTED CONNECTION
FOR ALTERNATE
(SEE NOTE 2)
ANGLE OR WT (TYP.)
BY DESIGN (TYP.)
SIZE AS REQ'D.
CONNECTION PLATE
(TYP.)
BY DESIGN
AS REQ'D.
TYPE K
(TYP.)
(TYP.)
(TYP.)
W.P.
(SEE NOTE 2)
ANGLE OR WT (TYP.)
(TYP.)
BY DESIGN
AS REQ'D.
SOLID PLATE
(TYP.)
~
BY DESIGN (TYP.)
SIZE AS REQ'D.
CONNECTION PLATE
(TYP.)
BY DESIGN
AS REQ'D.
BY DESIGN (TYP.)
SIZE AS REQ'D.
CONNECTION PLATE
DETAIL A
MI
N.
FILL LP
(TYP.)
•"
‡" BOLT (TYP.)
INTERMEDIATE DIAPHRAGMS
JACKING
LOCATIONS
* AS REQ'D.
BY DESIGN
(TYP.)
(TYP.)
(TYP.)
(TYP.)
STIFFENER
BEARING
(TYP.)L
(TYP.)
SOLE P
BEVELED
(TYP.)
1" MIN.
(T
YP.)
(SEE NOTE 3)
REQ'D. BY DESIGN
W-SECTION SIZE AS
1'-0" SPACING.
AND PROVIDE A SINGLE ROW OF ƒ"| STUDS AT A NOMINAL
3. FOR END DIAPHRAGMS, SUPPORT EDGE OF DECK WITH TOP CHORD,
WEATHERING STEEL BRIDGES ONLY.
BACK TO BACK DOUBLE ANGLES ARE PERMITTED FOR UNPAINTED
SHOULD TYPICALLY CONSIST OF SINGLE ANGLES OR WT SECTIONS.
2. MEMBER TYPE AND SIZE AS REQUIRED BY DESIGN. MEMBERS
1. REFER TO NOTES ON SHEETS 1, 2 AND 3 FOR DESIGN REQUIREMENTS.
(TYP.)
1" MIN.
(SEE NOTE 3)
BY DESIGN
SIZE AS REQ'D.
W-SECTION
BY DESIGN (TYP.)
SIZE AS REQ'D.
CONNECTION PLATE
(SEE NOTE 2)
ANGLE OR WT
(TYP.)
(TYP.)
(TYP.)
STIFFENER
BEARING
(TYP.)
SOLE �
BEVELED
(SEE NOTE 3)
SIZE AS REQ'D. BY DESIGN
OR W-SECTION DIAPHRAGM
WELDED PLATE GIRDER
BY DESIGN (TYP.)
SIZE AS REQ'D.
CONNECTION PLATE
(TYP.)
1" MIN.(TYP.)
1" MIN.
SIZE AS REQ'D. BY DESIGN
W-SECTION DIAPHRAGM
WELDED PLATE GIRDER OR
DIRECTOR, BUR. OF PROJECT DELIVERY
BEAR (TYP.)
FINISH TO
BEAR
FINISH TO
•"
•"
APR.29, 2016 APR.29, 2016
BD-619M
COMMONWEALTH OF PENNSYLVANIADEPARTMENT OF TRANSPORTATION
STANDARD
WITH REFINED METHODS OF ANALYSIS
CROSS FRAME AND SOLID PLATE
DIAPHRAGMS FOR STEEL BEAM/GIRDER
BRIDGES DESIGNED
SHEET 5 OF 5
CHIEF BRIDGE ENGINEER
RECOMMENDEDRECOMMENDED
BUREAU OF PROJECT DELIVERY
LO b
O LARGER OF 1.5 D AND 0.4 Lb
LO b
NOTE:
NORMAL TO THE GIRDER TANGENTS (SKEW 70° )
CONTIGUOUS CROSS-FRAME LINES (WITHIN THE SPAN )
ENTIRE SPAN NORMAL TO THE GIRDER TANGENTS (SKEW 70° )
DISCONTINUOUS (STAGGERED ) CROSS-FRAME LINES ALONG THE
SEVERELY SKEWED SUPPORTS WITH STAGGERED CROSS-FRAME LINES
PARALLEL TO THE SKEW (SKEW 70° )
SKEWED SUPPORTS WITH CONTIGUOUS CROSS-FRAME LINES
CONCEPTUAL FRAMING PLANS
CROSS-FRAME LINE ALONG THE SKEWED INTERIOR SUPPORT
SKEWED AND CURVED WITH DISCONTINUOUS CROSS-FRAME LINES
NO CROSS-FRAME LINE ALONG THE SKEWED INTERIOR SUPPORT
SKEWED AND CURVED WITH CONTIGUOUS CROSS-FRAME LINES
GIRDER BOTTOM FLANGE IS ADEQUATELY BRACED.
- WHERE A BEARING DOES NOT RESIST LATERAL FORCE,
THAT RESISTS LATERAL FORCE
- A CROSS-FRAME IS MATCHED WITH EACH BEARING
NEAR INTERIOR SUPPORTS, ENSURE THAT:
WHERE DISCONTINUOUS CROSS-FRAMES ARE UTILIZED
OF FABRICATION AND CONSTRUCTION AS WELL AS CONTROL OF FORCE EFFECTS.
DESIGNERS SHALL ESTABLISH A STRUCTURE SPECIFIC FRAMING PLAN, CONSIDERING ECONOMY
POTENTIAL FRAMING ARRANGEMENTS FOR VARIOUS CURVED AND/OR SKEWED BRIDGE GEOMETRIES.
THESE FRAMING PLANS ARE CONCEPTUAL ONLY AND ARE PROVIDED ONLY TO ILLUSTRATE
SKEWED INTERIOR SUPPORT LINES:
ARE ADEQUATELY BRACED.
AT BEARINGS THAT RESIST LATERAL FORCES AND FLANGE
- NOT NEEDED IF CROSS-FRAMES NORMAL TO GIRDER ARE
NORMAL TO GIRDER IS COMPLEX.
- DETAILING AT INTERSECTIONS WITH CROSS-FRAMES
SUPPORT LINE ARE NOT GENERALLY RECOMMENDED.
- FOR SKEWS < 70°, CROSS-FRAMES ALONG THE SKEWED
L0 b
0 LARGER OF 1.5 D AND 0.4 Lb
Lb 0
DIRECTOR, BUR. OF PROJECT DELIVERY
L BEARINGC L BEARINGC
L BEARINGC
L BEARINGC
L BEARINGC L BEARINGC
L BEARINGC L BEARINGC
L BEARINGCC
L BEARINGC
L PIER
L BEARINGC
L BEARINGC
CL PIER
APR.29, 2016 APR.29, 2016