Common Design Omissions

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Common Design Omissions

• Design Stage
• Affect on Quantities Post-Bid
• Affect on Contractor
• Affect on Relationships
• Enhancement of Construction Plans

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Common Design OmissionsDesign Phase

• Survey
• Subsurface Investigation
• In-House construction of plans

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Common Design Omissions Design Phase - Survey

• Control was not tied down
• Used bad control information
• Acquired insufficient or erroneous information
• Topo all tie in points
• Survey the existing crowns
• Use of companies with poor past history
• Same issues that contractors see
• Flight Data Use
• Accuracy

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Common Design Omissions Design Phase
Subsurface Investigation

• Insufficient or incomplete boring information
• Verification of information received

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Common Design Omissions Design Phase In House

• Plan sheets
• Construction Layout
• Missing data
• Profiles do not tie together
• Side streets tied in wrong
• Typicals Plan Sheets Cross Sections
• Different information
• Superelevations
• Missing typical sections
• Guardrail flares
• ROW
• Drainage ditches
• Drainage
• Incorrectly located
• Superelevations
• Low point
• Missing structures

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Common Design Omissions Design Phase In House

• Plan sheets
• Structures
• Alignments and elevations
• Sloping caps and abutments
• Boxouts
• Wall profiles
• Utilities
• Not shown on the plans
• Not depicted correctly
• How do we design around this information?

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Common Design OmissionsDesign Phase In House

• Plan sheets
• Erosion
• Areas are overwrought/untouched
• Silt Fence at cut slopes and shoulders
• Staging
• Site visits
• Staging
• Drainage
• Tapers
• Widths
• ROW
• Drainage
• Cost to cure information

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Common Design Omissions Affect On Quantities
Post Bid

• To the owner
• To the contractor
• To the designer

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Common Design OmissionsAffect on Contractor

• Resurvey
• Office calculations
• Project delay
• Quantity overrun
• Cost
• Quality
• Public Opinion

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Right now, your project would have to be
considered a disaster. I could have walked from
the fire station to Abernathy faster that was
able to drive. Yet once past Abernathy, I was
able to drive between 40 and 50 mph. There is a
major flaw in your design that I can't believe.
Just before Johnson's Ferry hits Abernathy coming
from Sandy Springs, the road used to expand into
two outbound lanes. That allowed you to queue up
twice the number of cars waiting for the next
green light. When that light turned green, those
cars were able to take off in a straight line,
rather than having to make a left turn. In other
words, your new intersection is about 40 as
efficient for all those commuters coming down
Johnson's Ferry. If this abysmal design is not
fixed, you will see accidents and potentially
violent behavior at Sandy Springs Circle and and
Johnson's Ferry road. Commuters will be furious
if today's experience is truly representative of
what you have created. I mean tar and feather,
fire someone furious. I hope there is better to
come. If not, someone in your office should
experience career consequences for such an
obviously horrible design. Regards,
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Common Design OmissionsAffect on Relationships

• Contractor is not a designer
• Understanding Design Intentions
• Adversarial Relationships
• How do we resolve problems?
• Time to review and absorb plans
• Building survey files
• Resolve discovered omissions/errors or correct
  the contractor
• Begin construction
• Stake the project and absorb the stakes
• Resolve omissions/errors discovered in the field
  (for the life of the project)
• The superiority of the three dimensional field

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Common Design OmissionsEnhancement of
Construction Plans

• Survey is the key
• Attention to detail
• Incorporate knowledge from past mistakes
• Neat and visible
• Willingness to listen and help
• No designer is perfect no contractor is perfect
• Compliment of views
• Give and take (Total cooperation from
  owner/designer/contractor)

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Common design omissions

• Questions or Comments