Difference between revisions of "903.3 Ground-Mounted Sign Supports"

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m (Form TR-15 added)
m (Per TS, updated to current practices. Eliminated outdated reference to sign production center and reclamation of old signs by the prison. Added guidance for the use of the Sign Management System. )
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[[image:903.2 Ground-Mounted Signs.jpg|right|300px]]
 
[[image:903.2 Ground-Mounted Signs.jpg|right|300px]]
  
Signs are ground-mounted whenever possible unless mounting overhead is justified. All ground-mounted structural and sheet signs are mounted on pipe posts, wide flange (WF) fabricated steel posts, u-channel posts, perforated square steel tube posts or wood posts as shown in the standard plans.
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==903.3.1 Post-Mounted Sign Installation==
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'''Guidance.''' Signs should be post-mounted whenever possible unless mounting overhead is justified.  
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'''Standard.''' All post-mounted structural signs and sheet signs shall be mounted on pipe posts, wide flange (WF) fabricated steel posts, u-channel posts, perforated square steel tube posts or wood posts as shown in the standard plans.  
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|'''Forms'''
 
|'''Forms'''
 
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|[[Media:903.2a Signpost Selection Guide.xls|Signpost Selection Guide]]
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|[[Media:903.2a Signpost Selection Guide 2014.xls|Signpost Selection Guide]]
 
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|[http://epg.modot.mo.gov/documents/903.2aPrintableSignpostSelectionGuide.xls Printable Signpost Selection Guide for use in the field]
 
|[http://epg.modot.mo.gov/documents/903.2aPrintableSignpostSelectionGuide.xls Printable Signpost Selection Guide for use in the field]
 
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Cross-sections of relocated or new signs are drawn and included in the final plans. The cross-sections are drawn to a 1" = 5' (1:50) scale to allow for scaling of quantities. The following information is shown for each sign:  sign number, station, edge of travelway, edge of shoulder, sign dimensions, guardrail and curb locations, post configuration, all non-standard horizontal and vertical clearances, backing bars and post lengths.  Random grid lines are used to draw the cross-section and elevations are not shown. For multiple post designs, number the posts from left to right, and use only one post design type per sign.  All cross-sections are drawn as the driver views the sign face. Existing signs relocated to new posts and posts being used in place are shown with dashed lines.  All back-to-back signs are noted, and the far sign is shown with dashed lines.  It is not necessary to outline the foundation size since this information is noted in the standard plans.  A note is added to the cross-section if the foundation depth is greater than the minimum shown in the standard plans. See [http://www.modot.mo.gov/business/standards_and_specs/documents/90303.pdf Standard Plan 903.03] for recommended foundation depths for various post designs and slopes.  The post stub length is shown below the finished ground line in order to scale the correct post pay length.  [[media:903.2 Example Cross Sections Apr 10.pdf|Acceptable examples of ground-mounted cross-sections]] are available.
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Cross-sections of relocated or new signs shall be drawn and included in the final plans. The cross-sections are drawn to a scale of 1 in. = 5 ft. (1:50) to allow for scaling of quantities. Random grid lines shall be used to draw the cross-section and elevations are not shown. All cross-sections shall be drawn as the driver views the sign face. A note shall be added to the cross-section if the footing depth is greater than the minimum shown in the standard plans.
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The following information shall be shown for each sign:
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:* Sign number
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:* Station
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:* Edge of traveled way
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:* Edge of shoulder
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:* Sign dimensions
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:* Guardrail and curb locations
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:* Post configuration
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:* All non-standard horizontal and vertical clearances
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:* Backing bars and post lengths
  
Whenever possible, available overhead sign support structure columns, signal poles, etc. are used to mount sheet signs.  This is less expensive and encourages cross comparisons of signal and signing plans.  Utility poles are not used to mount signs.
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For multiple post designs, the posts shall be numbered from left to right, and only one post design type per sign shall be used.  
  
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Existing signs relocated to new posts and posts being used in place shall be shown with dashed lines.
  
==903.2.1 Horizontal Clearances (MUTCD Section 2A.19)==
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All signs that are back-to-back shall be noted and the far sign shall be shown with dashed lines.
  
'''Standard.'''  For [[903.3 Overhead Guide Sign Mounting|overhead sign]] supports, the minimum lateral offset from the edge of the shoulder (or, if no shoulder exists, from the edge of pavement) to the near edge of overhead sign supports (cantilever or sign bridges) shall be 6 ft.  Overhead sign supports shall have a barrier or crash cushion to shield them if they are within the clear zone.  
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It is not necessary to outline the footing width and depth since this information is noted in the standard plans.
  
Ground-mounted sign supports shall be breakaway, yielding, or shielded with a longitudinal barrier or crash cushion if within the clear zone.
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The post stub length shall be shown below the finished ground line in order to scale the correct post pay length.  
  
'''Guidance.'''  For ground-mounted signs, the minimum lateral offset should be 6 ft. from the edge of the travelway.  If an existing shoulder is wider than 6 ft., the minimum lateral offset for ground-mounted signs should be 6 ft. from the edge of the shoulder or front face of curb.   
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'''Guidance.''' Utility and light poles should not be used to mount signs as they are either not the property and maintenance responsibly of MoDOT or are not designed to carry the additional wind loading a sign adds to the structure.
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'''Option.'''  In areas with space restrictions, available sign truss columns, signal poles, bridge columns or other significant MoDOT structures, excluding roadway lighting structures, may be used to mount flat sheet aluminum signs.
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'''Support.''' See [https://www.modot.org/media/16921 Standard Plan 903.03] for recommended footing depths for various post designs and slopes.
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==903.3.2 Lateral Offset (MUTCD Section 2A.19)==
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'''Standard.'''  Post-mounted sign supports shall be crashworthy (breakaway, yielding or shielded with a longitudinal barrier or crash cushion) if within the clear zone.
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'''Guidance.'''  For post-mounted signs, the minimum lateral offset should be 12 ft. from the edge of the travelway.  If an existing shoulder is wider than 6 ft., the minimum lateral offset for post-mounted signs should be 6 ft. from the edge of the shoulder or front face of curb.   
  
 
Where existing signs are located within 6 ft. of a utility pole, they should be relocated to provide a minimum distance of 12 ft. where practical through normal sign replacement.   
 
Where existing signs are located within 6 ft. of a utility pole, they should be relocated to provide a minimum distance of 12 ft. where practical through normal sign replacement.   
  
EXIT signs placed in the gore only require a 2 ft. horizontal clearance from both edges of shoulder or front face of curbs.
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EXIT signs placed in the gore only require a 2 ft. lateral offset from both edges of shoulder or front face of curbs.
  
For divisional and channelizing islands, a 2 ft. offset should be maintained between the edge of sign and the front face of curb.  For islands with restricted width the sign should not extend beyond the curb.  When signing at the nose of a 4 ft.