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					             2008 FDOT/FTBA CONSTRUCTION CONFERENCE




   Critical Construction Issues
           By Rafiq Darji
QPL v/s Specification requirements.


Steel Girder Erection issues.


Picket Railing on Bridges.


Concrete Field Technician Level II
requirements.
   FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
                     2008 FDOT/FTBA CONSTRUCTION CONFERENCE



  QPL v/s Specification Requirements
 Selecting a product from the QPL does not by itself
  constitute final acceptance of that product.

 Final acceptance of a product is granted only when it is in
  full compliance with applicable specifications, which may
  require that the product be manufactured by a producer
  who is qualified by the Department and is on the State
  Materials Office (SMO) list of “Producers with Acceptable
  QC Programs” .
     The list can be obtained at the following website:
     http://www.dot.state.fl.us/statematerialsoffice/qualit
       y/programs/qualitycontrol/materialslistings/postjul
       y2002.htm
       FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
                        2008 FDOT/FTBA CONSTRUCTION CONFERENCE




     Currently SMO website has 15 lists depending on the category
      of product. The following is a summary of those items on
      the QPL by category that are required to be on an approved
      producer list of the SMO website.
 Precast Temporary Barrier Wall (Specification 521), Sound Barrier
  Panels (Specification 534), Retaining Wall Panels (Specification 548) and
  Concrete Strain Poles (Specification 641): SMO List – Concrete Sources
  –Precast Incidental, Drainage and Pipe
 Galvanizers for Guardrail (Specification 536) Roadway Sign Supports
  (Specification 700-2.3) and Light Poles (992-2.1): SMO List – Coatings
  Sources
 Steel Strain Poles, Steel Mast Arms and Monotube Assemblies
  (Specification 649) and Steel and Aluminum Light Poles (992-2): SMO
  List - Metal Fabricators
 Aluminum Pedestrian-Bicycle Railing (Index 860) and Aluminum Pipe
  Guiderail (870): SMO List – Metal Fabricators


          FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
                     2008 FDOT/FTBA CONSTRUCTION CONFERENCE




 If the component is not manufactured by a producer on the
  SMO list then even if it appears on the QPL, it may not be
  accepted for use on a Department project.


 Where required, the product must be stamped by the
  producer which signifies that the product has been
  manufactured in full compliance with the producer's QC
  Plan and the applicable specifications and the required
  certifications.




       FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
                     2008 FDOT/FTBA CONSTRUCTION CONFERENCE




 Here is an example of typical specification requirements.


 For Prestressed Concrete Poles, the Section 641-1 says,
  “Obtain precast, prestressed concrete poles from a
  manufacturing plant that is currently on the Department’s
  list of qualified precast, prestressed concrete plants and
  listed on the Departments Qualified Products List (QPL)”.


 Look out for a DCE memo that will be issued very shortly
  emphasizing this issue.




       FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
                       2008 FDOT/FTBA CONSTRUCTION CONFERENCE



               Steel Girder Erection Issues
There has been more than one incident where beams did not fit
between the end bents or beam seats after they were fabricated and
erected. Hence, the beam ends had to be cut in the field and jacking
was performed to accommodate the as-built conditions.

Do your homework prior to erecting the girders : Verify the as-built
 locations of the piers and beam seats with respect to the plans
dimensions. If there are any differences, fix them in the shop prior to
shipping or on the ground prior to erecting. Any repair work done after
the erection will be difficult, costly, risky and unsafe.

Verify backwall plumbness. Out of plumbness of the backwall
combined with geometry and temperature effects on the girder will
pose serious fitting issues.


         FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
                 2008 FDOT/FTBA CONSTRUCTION CONFERENCE


 If any jacking is required to correct the miss alignment
after the erection, place jacks at the plans specified
locations. Placing jacks at different locations may damage
the pier caps and/or girders. Communication between the
Contractor and CEI is very critical in achieving the success.
Have a meeting prior to jacking operations.

Erection during hot weather conditions may pose more
challenges especially for those girders where high skew,
steep superelevations and tight horizontal curvatures exist.
Watch out for length variations due to temperature rise/fall.

If possible, erect girders at fix bearing first. Adjustments
and fit up at the expansion bearing can easily be
accommodated due to the presence of slotted holes, sliding
surfaces, etc.



   FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
                        2008 FDOT/FTBA CONSTRUCTION CONFERENCE




 Do not apply lateral or longitudinal forces on to the girder system
without releasing all the restrains. Otherwise, you may introduce
torsional moments into the girder system.

Do not force the girders to fit in to the anchor bolt holes. Otherwise,
this may introduce locked-in forces into the girder system.

Verify that the anchor bolt block-out locations are in compliance with
the plan details prior to concrete placement.

Make sure that the anchor bolt block-out formwork is secured and
stable during concrete placement operations. if it is displaced, new holes
needs to be cored into the cap, which may damage the existing cap steel
and may affect the design. An Engineer’s approval will be required prior
to any coring.


          FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
                    2008 FDOT/FTBA CONSTRUCTION CONFERENCE



       Aluminum Pedestrian /Bicycle
       Picket Railing on Bridges
Due to some recent failures in the welded connections of
picket railings, the Department has modified the Standard
Index No. 860 (2008 version) to allow non-welded connection at
the top.

Previous Index details require welding at both top and
bottom picket connections.

Now, on Bridges only, the index requires non-welded
connection between the picket and top rail and welding
connection between the picket and bottom rail.

Non welded connection is optional for other locations; such
as for roadway applications.

      FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
              2008 FDOT/FTBA CONSTRUCTION CONFERENCE



 Here are some photographs of
 failed picket rails




FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
              2008 FDOT/FTBA CONSTRUCTION CONFERENCE




FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
              2008 FDOT/FTBA CONSTRUCTION CONFERENCE




FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
              2008 FDOT/FTBA CONSTRUCTION CONFERENCE




FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
                    2008 FDOT/FTBA CONSTRUCTION CONFERENCE

               I encourage incorporating this detail
               in all ongoing bridge projects, If this is
               possible.




Index 860 : Non welded Picket and Top Rail
Connection Detail

      FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
                        2008 FDOT/FTBA CONSTRUCTION CONFERENCE



                   Concrete Field Technician
                   Level II requirements
The Specification Section 105-5.7.2 requires a level II technician must be
present on the jobsite during all concrete placements on major bridge
projects. Prior to the placement of concrete, the technician will inspect
the element to be cast to ensure compliance with Contract Documents.

The following questions have been raised many times on the above
requirements,
    Is this indented to apply only to placements that are structural
    elements of the major bridge as opposed to all placements of
    structural concrete anywhere on a project that includes major
    bridge, e.g. inlet tops, etc.?
    Is the reference to inspection prior to casting intended to require
    that only a level II inspector is qualified to do a pre-placement
    inspection or that a level II technician supervise the process as with
    testing plastic properties?
          FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
                           2008 FDOT/FTBA CONSTRUCTION CONFERENCE


Here are clarifications to those questions;

The level II requirement applies only to placing components of a major bridge and
not to all placements on a project which includes a major bridge. The Specification
105-5.7.2, is intend to apply to structural components of major bridges including
decks, caps, footings, columns, crash walls, abutments, barrier walls etc. The type
of structures that are considered to be MAJOR are defined in Specification
5-1.4.1(e).

The Level II Technician must personally inspect form work (bracing, alignment,
dimensions, etc.), rebar placement (positioning, size and quantity), screed
operation, preparation for curing and inclement weather and evaporation rate
monitoring to name some of the items to be checked, prior to the actual placement
of concrete.

During the actual concrete placement process (delivery, sampling, testing, record
keeping, concrete placement, vibration, screeding, finishing, evaporation
monitoring, curing, etc.) the Level II Technician should be present at the site of work
in progress.


             FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
                        2008 FDOT/FTBA CONSTRUCTION CONFERENCE




Having said that, one may ask, why is level II technician not required for
minor bridges? Is this because the quality on minor bridges is not as
important as on major bridges ?

There is no doubt, quality on minor bridges is as important as on major
bridges. But, due to the scarcity of Level II Technicians, the Contractors
would have a very hard time to find and supply Level II Technicians for all
bridge projects. Hence, the Department in conjunction with the Contractors
had decided to have this requirement only for major bridges.




          FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
                        2008 FDOT/FTBA CONSTRUCTION CONFERENCE



                  Department’s Future Direction
                  on the Level II Requirements

In order to be a Level II qualified, the Construction Training and
Qualification Manual (CTQM) requires an ACI CTCI certification. This
course is difficult and covers topics other than bridges, which has been
a problem for Contractors. In order to address this issue, at present, the
ACI is at the final stage of developing a new course concentrating on
roads and bridges. After the course is finalized and accepted by the
Department (i.e. TRT), the course will be offered to the public.

Once this is done, a year after this date, the Department will require
Level II technicians for Contractors in all bridge projects regardless of it
being a minor or a major bridge project. The one year time is allowed so
that the Contractors have sufficient time to train their personnel and
take the required course.

          FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
                       2008 FDOT/FTBA CONSTRUCTION CONFERENCE



                                 REMINDER

Due to variety of quality problems on Category 2 (C2) construction
projects, few years ago, a memo (No.17-05) was issued to clarify the
role of State Construction Structures Engineer (SCSE) on C2 bridge
construction projects .


Require notification and consultation with the SCSE by the CEI
staff on technical matters such as any proposed deviation from the
plans and specifications; Contractor means and methods that might
adversely impact the performance or durability of the finished bridge;
and Contractor proposed corrections of damaged or defective
structural components.



         FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE
              2008 FDOT/FTBA CONSTRUCTION CONFERENCE




FLORIDA DEPARTMENT OF TRANSPORTATION – STATE CONSTRUCTION OFFICE

				
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