751.18 Concrete Multicell Box Girder Bridges

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751.18.1 Reinforcement

751.18.1.1 Single Column Design

Top Slab Modifications at Intermediate Bent:

The reinforcement shown below shall be used in place of the design slab steel.


(1) designed slab steel


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SECTION AT INT. BENT
(SINGLE COLUMN)

751.18.1.2 Web Reinforcement

Top Slab Modifications at Intermediate Bent:

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TYPICAL SECTION THRU WEB & SLABS

751.18.2 Miscellaneous Details

751.18.2.1 Access Doors

ACCESS DOORS (RECTANGLE)

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PLAN


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SECTION A-A


DETAILS OF ACCESS DOORS
WEIGHT 179#


ACCESS DOORS (OVAL)

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PLAN


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SECTION A-A


DETAILS OF ACCESS DOORS


751.21 cont conc box girders oval access door details.gif

See Section 4A for painting or galvanizing note.


ACCESS DOORS LOCATION

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  • Generally, access doors shall be positioned on or near 1/4 point of span and centerline of roadway.

It is permissible to shift position of access doors when:

  1. Girder is located at centerline of bridge
  2. To prevent cutting additional slab bars
  3. To clear construction joints
  4. To maintain adequate vertical clearance

If possible, do not locate access doors over a roadway or berm.

751.21 cont conc box girders access door reinforcement.gif
PLAN OF ACCESS DOOR
SHOWING REINFORCEMENT