3 Construction Approachx

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25 Νοε 2013 (πριν από 4 χρόνια και 1 μήνα)

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1.0
Construction Methods

Schedule

The project will be constructed by
working in
multiples area at the same time as shown in the
project schedule. During Phase I, a minimum of
5 crews will work in 3 locations to construct
foundations, substructure, demolition and
superstructure. Work will occur 6 days per week.
Two 10 hour
shifts per day will be utilized.


Once the foundations are completed for Phase I,
the foundation crews can begin work on the
foundations for Phase II and III that do not
require any removal of the existing bridges.
Upon completion of Phase I, the traffic
will be
shifted to a new pattern and Phase II and III
will be constructed by working in multiple
project locations at the same time.



Each unique location will have a project
assigned superintendent and engineer dedicated
to that specification location/sh
ift. The Johnson
Bros/EC Driver team will complete the project in
509 days by utilizing this aggressive approach.
The four ramps will be reconstructed in a total
time of 26 days (Morgan Street
-

7days,
Jefferson Street
-

6 days, Kennedy Boulevard
-

7
days,

and Nebraska Avenue 6 days). The
Johnson Bros/EC Driver team will accomplish
this by placing a unique crew on each span for
demolition and redecking. The concrete for the
entire ramp will be placed in one pour. The
ramps will be reopened when concrete bea
ms
indicate proper strength. Curing water will be
kept on the ramps while they are under traffic to
achieve the minimum 7 day wet cure.


Maintenance of Traffic

Maintenance of traffic plans will be developed
during the design phase and implemented
during th
e construction phase. To help maintain
traffic flow as planned, clearly announced and
delineated travel lanes and work areas will be
maintained. This will create a safer environment
for the traveling public and the construction
teams. To properly mainta
in these areas, MOT
devices will be inspected and recorded at a
minimum at the beginning and end of each shift
with corrections implemented immediately.


Pavement markings will be permanently
removed and not covered up with tape, when no
longer required
. Staging of materials and
equipment will be kept out of areas that could
provide an impact or site hazard to motorist.
Working equipment will be kept out of active
travels lanes. If travel lanes may be affected,
work will be scheduled when lane closures
are
allowed, to reduce impact to motorists, residents
and local businesses.


Lane closures will be kept to a minimum and will
be coordinated with FDOT and THEA. Advance
warning to motorist will be provided as it relates
to upcoming changes in traffic pat
terns or the
instances of night time lane closures and pacing
procedures for girder erection. MOT will be
established by placing Type K barrier wall in
locations shown in plans. Crash drums will be
utilized instead of bolt down attenuators for
ease of relo
cation. Temporary striping will be
placed and removed as shown in plans. The
MOT will be placed and moved ahead in 1.5 unit
increments so that traffic disruption will be keep
to a minimum.



Work Areas and Traffic Operations

The proposed schedule includes
the division of the
project into three work zone segments, each with
unique construction and operational characteristics:



Segment A:
Begin Project to the WB Morgan
Street Exit Ramp and EB Jefferson Street
Entrance Ramp which includes viaduct deck
replaceme
nt and inside transition widening of
viaducts for EB Spans 27
-
46 and WB Spans 25
-
43.






Segment B:

WB Morgan Street Exit Ramp and
EB Jefferson Street Entrance Ramp to 12th Street,
which includes viaduct and ramp deck
replacement and inside widening of viaducts for
Spans EB Spans 47
-
93 and WB Spans 44
-
91.


Overall Construction Sequencing and
Traffic Con
trol Approach

The proposed TCP provides a simple and flexible
scheme that can be adjusted to seasonal or
event oriented traffic demands. A simplified
overview of the Traffic Control Plan includes:


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Phase IA includes median widening in
Segments B and C and

median deck
panel replacements in Segment B



Phase IB includes median deck panel
replacements in Segment A



Phase IIA includes outside deck panel
replacements in Segment A



Phase IIB includes outside deck panel
replacements in Segment B and outside
widening
in Segment C


The flow of construction activities will start at
the interface of Segments B and C, with
separate crews progressing east and west of this
location to the ends of the project and then
back to the interface point. Two 11
-
foot
-
wide
lanes of tr
affic will be maintained for peak hours
for all construction phases in work Segments B
and C, due to the additional foot of widening
provided in Segment B. Extended single lane
closures will be required for Segment A for the
short duration of Phase IB and

IIA.



Two lanes of traffic will be maintained in each
direction through all work zones with the
exception of the deck replacement portion at the
beginning of the project. When traffic is reduced
to a single lane in a given direction, a tow
vehicle will b
e onsite at all times to assist
motorists who become disabled inside the
project limits. Construction travel route signs will
be posted for emergency situations where it is
necessary to have two travel lanes in each
direction. Side streets below the expres
sway will
be utilized in these situations.



Removal of Existing Structures

Deck

False deck panels will be installed to prevent
concrete debris from falling to the areas below.
The existing deck to be replaced will be
removed by saw cutting to the top of t
he
precast deck form panels. A back hoe with a
slab bucket will be utilized to remove the form
panels.


Concrete on top of beams will be cleaned off by
hand using pneumatic chipping guns. Care will
be exercised to prevent damaging shear bars on
top of t
he girders. A detail will be included in the
contract plans to replace any shear bars that are
damaged during concrete removal. All concrete
will be taken off site and recycled.


The existing fiber optic lines on the East and
West bound lanes will be lowe
red onto a new
bracket installed on the new girders erected for
the new widened portion of the expressway.
This will prevent the fiber optic cable from
needing to be temporarily supported thus
minimizing the chance of damage.



Superstructure

New Florida
I
-
Beams and AASHTO girders will
be erected as shown in the plans. Girder
delivery in the area of the REL will require
girders to be taken from the existing expressway
and lifted utilizing hydraulic cranes from the
area below. Girders will be profiled prior

to
erecting the rhino style SIP forms. Profiling the
girders provides for proper location of SIP forms
to achieve the desired deck thickness/build up
over girders. Reinforcement steel will then be
installed. Upon completion of rebar installation,
all ar
eas of the deck will be properly cleaned
and a dry run of the deck will be conducted with
the deck finishing machine to assure proper
reinforcement cover and deck thickness. Dry
running of the deck finishing machine also
confirms that adjacent decks proper
ly tie into
each other.


Substructure

In areas that have driven H
-
piles, a concrete
footer will be formed and cast in place. Areas
that have drilled shafts will not require a footer.
Precast columns and caps will be cast off site to
facilitate the constr
uction schedule. Columns
and caps will be delivered to the site and
erected. Foundation and substructure
construction will be completed prior to beginning
superstructure demolition to minimize disruption
to traffic.



Foundation

Foundations will be constru
cted utilizing a either
steel H
-
piles (HP 14x 117) or drilled shafts.
Drilled shafts will be required in some areas to
prevent vibration damage to existing structures.
Drilled shafts will also be utilized in locations
where space requirements prohibit th
e
construction of a footing. Areas around the REL
that have head room limitations will be
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constructed by using a bauer type machine that
has a telescoping mast and can be fitted with an
auger, vibratory hammer or impact hammer as
required. Conventional cra
wler cranes will be
utilized in other locations.



Roadway

Environmental concerns will be alleviated by
using Best Management Practices (BMP)
throughout the construction area, which
includes sodded side slopes and appropriate
erosion control measures. Upo
n approval by
the Department, the SWPPP will be
implemented in construction. The team is
providing an on
-
site FDEP
-
trained inspector to
conduct monitoring, erosion and sediment
control measures, and to ensure the overall
compliance with the requirements o
f the NPDES
permit. In addition, we will maintain additional
silt fence, floating turbidity barrier, equipment
and other materials required to correct any
emergency deficiencies that may occur.


Existing utilities will be protected by using
proper locat
ing and construction procedures.
One of the first requirements on any project is
to notify utility owners of the intent to dig. Prior
to digging on any project, Johnson Bros. stakes
the limits of the proposed affected area. A
Sunshine State One Call wor
k order will be
placed and filed. It is also imperative to notify
any local utilities that may not be part of the
one call system. With the utilities located, any
conflicts can be determined with the proposed
construction. Once a conflict is identified

the
project team will coordinate with the utility
owners immediately to expedite a resolution to
the conflict. Overhead utilities will be flagged
and posted. A spotter will be implemented
where there is the potential for a wire strike.



Safety

Johnson Bros. has a “zero tolerance” policy
when it comes to accidents and renews this
pledge annually and on each new project. Our
established Safety Program will be tailored
to
meet the requirements of the

Project. Standard
safety policies include daily
Safety Task Analysis
Talks, crane and rigging inspections, weekly
Tool Box Safety Meetings, bi
-
weekly
Management Safety Meetings, Critical Lift
Procedures for structures erection, and pre
-
planning meetings implemented before each
new phase of work. Being s
afe is part of the
culture at Johnson Bros., and every project’s
first concern is to make sure our employees
return home safely every night.

Particular safety measures that will be
implemented on this project include providing all
workers with the proper p
rotective equipment
for their job,
the use of physical barriers
between workers and traffic when practical,
attaching tie
-
off lines prior to girder erection,
installing hand railing to address drop
-
off
concerns as the MSE walls are erected,

and the
use of
spotters when working around overhead
lines. Critical elements of our safety plan that
will receive the highest level of priority on this
project are:

Crane and Girder Erection Safety

In 1998 Johnson Bros.
,

began sending its crane
operators, foreman,
supe
rintendents
, project
engineers, project managers, estimators, and
senior management to the National Certification
of Crane Operators. Although at that time it
was not required by OSHA, we had developed
our crane safety program around the new
requirements
of certifying crane operators.


Johnson Bros. has a “Critical Lift” program to
cover “Dual Crane Lifts”, any lift that is
greater
than

75% of the manufacture
r’
s chart, and any
lift
greater than

20 tons. Dual crane picks will
be implemented during the structural steel
erection. The “Critical Lift” program along with
a steel erection plan will be followed for the
placement of the steel girders. A detail
procedure will be drafted showing crane,

load,
transport and support locations, girder weights,
crane capacities, rigging, and other critical
elements. Multiple drawings will be utilized to
show erection sequence both in plan and
elevation views. Where temporary shoring
elements are required,
detailed shop drawings
will be submitted, signed and sealed by an
engineer on our staff. A pre
-
erection meeting
will be held with all involved field personnel, so
doubt will exists of a team member’s
responsibility during the actual erection. A
similar p
rocedure will also be utilized for the pile
rigging and driving during foundation
construction.

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While crane safety always is a focus of our
safety program, our team’s efforts on this
project will be of particular importance due to
the proximity of power li
nes to the work zone.
The recent enactment of the new OSHA crane
safety standard will provide further impetus for
all operations involving cranes to receive more
attention than normal. In accordance with the
new OSHA standard, some of the enhanced
safety t
echniques that may be employed when
lifting activities will place equipment components
within the specified distance are:



De
-
energize power lines.

We
will work

closely with
TECO

to determine if any of
the power lines need be de
-
energized due
to clearance r
equirements. This will
provide the best protection against
electrical damage to equipment and/or
personal injury.



Use of trained spotters to alert the
operator of proximity to power lines.

Air
horns may be used to alert the operator of
such dangers.



Groun
ding of equipment.

If deemed
necessary, lifting equipment will be
grounded to minimize the effect of
electrical energy passing through the
equipment.

Fall Protection

It is our policy to perform work in the safest
manner possible, consistent with applicabl
e
codes, sound construction practices, and quality.
Employees working/walking on platforms or
surfaces with unprotected sides or leading edge
that are six feet or more above a lower level, or
if there is a hazard in less distance, must be
protected from fa
lling. Our fall protection policy
and guidelines will apply in selecting and
implementing systems to manage fall hazards.
Among such systems that may be employed are
guardrails and full body harnesses with lanyards.


Public Safety

Since a majority of the
work will be performed
over a public waterway,
public safety is a
foremost concern.
Methods to limit incidents
are; to have all work that is performed utilize an
approved TTCP and supervised by an ATTSA
work zone safety supervisor, clearly delineate
trave
l lanes, adequately protect drop off
conditions, keep equipment and materials out of
sight lines, the complete removal of
inappropriate pavement markings, and the use
of variable message boards to inform motorists
of current and upcoming traffic configurat
ions.


Partnering

Design/Build is inherently a partnership, so it
makes sense to apply the partnering process to
this project to create a win
-
win environment for
all parties involved. Partnering has enjoyed
great success in the transportation industry and
helped to change
attitudes, create lasting
stakeholder relationships and encourage
innovative solutions that benefit the ultimate
customer


the traveling public and the
taxpayers of Florida. Partnered projects, on
average, result in higher quality, faster
completion time
s and satisfied team members
who look forward to working together again. It
is exactly the kind of results we want to achieve
on this project.


It is our belief that the Partnering process, used
so successfully in construction projects, will
exceed that

level of effectiveness on this
design/build project. Partnering offers the best
opportunity for the clear, open communication,
responsiveness, trust and issue resolution that
will be critical to the mutual success of all
parties in a design/build atmosph
ere. To
provide the most functional, cost
-
effective
facility, it is imperative that the Design
-
Builder
selected for the project along with the owners
and other stakeholders, form a well
-
defined
project team with a process for building
relationships and re
solving challenges.


Summary

The JBC/EC Driver construction approach allows
construction to take place in multiple locations
at the same time and therefore limit total
construction time. This approach limits exposure
for the traveling public. The shortened

project
duration also reduces costs by decreasing
monthly project overhead and material cost
escalation. Our team has analyzed the project
inside and out to determine the resources
required to construct the project in a timely cost
efficient manner. The
team has utilized higher
strength concrete than required to increase
durability of the structure. Class IV 5,500
concrete will be used for the superstructure and
Class VII 8,500 will be used for the precast
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substructure. Most of the substructure will be
pr
ecast to cut down on deliveries that create
additional traffic and noise.