Embed Size (px)
Citation preview
II--10 NEW BRIDGE10 NEW BRIDGECRITICAL FEATURES:CRITICAL FEATURES:•• Six lane facilitySix lane facility
•• Storm protectionStorm protection
•• Enhanced ship collision resistanceEnhanced ship collision resistance
•• 75 year service life75 year service life
•• Design alternates where possibleDesign alternates where possible
GENERALGENERAL FACTSFACTS
•• TotalTotal Bridge Length = 58,388Bridge Length = 58,388’’–– 260,000 LF 36260,000 LF 36”” Piles or 200,000 LF ShaftsPiles or 200,000 LF Shafts–– 257,000 LF BT 78 or 44,000 LF Segmental257,000 LF BT 78 or 44,000 LF Segmental
•• Surface area = 3.75 million ftSurface area = 3.75 million ft22
•• Total Roadway Length =1.2 milesTotal Roadway Length =1.2 miles
GENERAL FACTSGENERAL FACTS
CONTRACT #1CONTRACT #1•• Transition spans, mid level spans and roadwayTransition spans, mid level spans and roadway•• Expected Letting Date: Spring 2006Expected Letting Date: Spring 2006
CONTRACT #2CONTRACT #2•• High level and remaining roadwayHigh level and remaining roadway•• Expected Letting Date: Summer 2006Expected Letting Date: Summer 2006
BRIDGEBRIDGE LOW LEVEL LOW LEVEL -- TRANSITIONTRANSITION
•• SuperstructureSuperstructure (no alternates)(no alternates)1 mile long Type III and flat slab1 mile long Type III and flat slab
•• SubstructureSubstructureConcrete bents with 36Concrete bents with 36”” concrete concrete piles or 66piles or 66”” drilled shaftsdrilled shafts
TYPICAL SECTION (Type III)TYPICAL SECTION (Type III)
BRIDGE MID LEVEL PORTIONBRIDGE MID LEVEL PORTION
•• SuperstructureSuperstructure8 miles8 miles of Segmental Construction or of Segmental Construction or 7878””BT Girders, span range 135BT Girders, span range 135’’ to 155to 155’’
•• SubstructureSubstructureConcrete bents with 36Concrete bents with 36”” concreteconcrete piles piles or 66or 66”” drilled shaftsdrilled shafts
If you need If you need to add to add
anythinganything
Alternate ABT-78”
Alternate AAlternate A--1: 361: 36”” Concrete PilesConcrete Piles
Alternate A-2 : Typical Section66” Diameter Drilled ShaftsAlternate AAlternate A--2 : Typical Section2 : Typical Section6666”” Diameter Drilled ShaftsDiameter Drilled Shafts
Alternate B:Segmental
Typical Span LayoutTypical Span Layout
Typical SectionTypical Section
Span by Span ErectionSpan by Span Erection
Superstructure Erection SchemeSuperstructure Erection Scheme
If you need If you need to add to add
anythinganything
ConstructionPhasing
CONSTRUCTION PHASINGCONSTRUCTION PHASING•• Phase IPhase I
–– Low & midLow & mid--level approach bridgeslevel approach bridges
•• Phase IIPhase II–– Main span unit and approachesMain span unit and approaches
•• Phase IIIPhase III–– Demolition of existing bridge at connections Demolition of existing bridge at connections
and completion of bridge structuresand completion of bridge structures
Critical Path Critical Path –– 1 complete bridge open in 30 1 complete bridge open in 30 mos.mos.
CONSTRUCTION PHASING CONSTRUCTION PHASING OBJECTIVESOBJECTIVES
•• Complete one useable bridge in one directionComplete one useable bridge in one direction
•• Improve Level of Service for the motorist at Improve Level of Service for the motorist at each stage of constructioneach stage of construction
•• Provide maximum access for the contractor Provide maximum access for the contractor during constructionduring construction
•• Maintain at least two lanes of traffic in each Maintain at least two lanes of traffic in each direction throughout constructiondirection throughout construction
Top Down Construction Methods
I-310 & La. 1 Construction
Top Down Construction Methods
End On Construction - build the new bridge from the previously constructed portion of the new bridge.
Forward Construction – building the new bridge from a temporary construction bridge forward of the new bridge construction.
Top Down Construction Methods
Construction by the forward construction method allows for a gradual application of permanent loads to be applied to the new structure, therefore allowing time for pile set up and the construction to advance at a quicker rate. However, the cost of the work bridge should be considered in the decision of construction methods.
Interstate I-310End On Construction Method
La. 1 ProjectForward Construction Method Utilizing a Work
Bridge
Cone Tip Resistance, qc
Slee
ve Friction, f
s
Penetration Rate: 2 cm/sec
Cone Penetration Test (CPT)Base area = 10 cm2
Sleeve area = 150 cm2
Cone angle = 60o
Equipment used to obtain CPT Data and Equipment used to obtain CPT Data and BoringsBorings
Repeatability of CPT
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Dep
th (m
)
0 10 20 30 40 50
Tip Resistance (MPa)
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
0.0 0.1 0.2 0.3 0.4 0.5
Sleeve Friction (MPa)
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
0 2 4 6 8 10
Rf (%)
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
0.0 0.5 1.0 1.5
Pore Pressure (MPa)
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
0 20 40 60 80 100
Probability of soil type (%)
Clayey
Sandy
U1
Silty
Qt/Q0 = 0.4271Log(t/t0) + 1R2 = 0.9509
Qs/Q0 = 0.4435Log(t/t0) + 1R2 = 0.9924
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
0.001 0.01 0.1 1 10
Rel
ativ
e R
esis
tanc
e (t 0
= 1
day)
Elapsed Time (days)
T-2 16-inch 109 Feet Penetration
Total ResistanceSkin Friction Only
520’ Forward Construction Zone
Drive Steel Temp. Piles & Set Trestle Drive Permanent P.C.C. PilesSet Pre-Cast Conc. Caps
520’ Cure Form & Pour Zone Set Precast Conc. Voided Slabs or GirdersSet Deck Side Forms w/Rail for ScreedSet Deck Reinforcing SteelPour & Cure Concrete Decks
520’ Rear Construction Zone Remove Steel Temp. Piles &Temp. Crane/Tread Rails Transport and Off Load Materials/Supplies Forward
THE END
US 90
HUEY P. LONG BRIDGE WIDENING
In order to determine the existing condition of the main piers prior to construction, the Department in cooperation with the New Orleans Public Belt Railroad utilized acoustical imaging to acquire a global image of the piers in the muddy water of the Mississippi.If damage was uncovered, a more detailed investigation would have been initiated.
THE END
QUESTIONS:1. What was the primary reason for dredging a channel in
the ground prior to the construction of the I-10 bridge going through Louisiana?
2. What were the reasons why dredging was not allowed in later years?
3. Are there any formal guidelines or specifications adopted by AASHTO on the subject of accelerated construction methods?
4. What was the primary reason for the devastation and loss of life in the metropolitan New Orleans as a result of the Hurricane Katrina?
5. What is meant by the term “Top-Down-Construction”?6. What is a SPMT?
ANSWERS:1. Dredging in wetlands would allow ease of construction by giving the contractor direct access to
the construction site through various navigable waterways. This made construction more convenient and faster. It also allowed ease of shipping construction elements such as piles and girders to the job site.
2. Dredging in wetland often interfered with the natural echo system and resulted in the environmental damage. Wetlands are very different than lakes or deeper waterways and their conversion into other types of waterways is no longer allowed.
3. In some instances dredging also allowed for salt water intrusion and thereby converting freshwater into Brackish water which is harmful to the freshwater natural habitat.
4. There are no standards for the acceleration of construction. There are many ways to expedite construction and each method will necessitate the formulation of its unique specifications and engineered plans.
5. The primary reason for devastation and loss of life in New Orleans was not the hurricane wind intensity but rather the breach of the city’s Levee systems.
6. Top-Down-Construction or sometimes referred to as End-On-Construction is a method of construction whereby the damage to the construction surroundings is minimized by virtue of advancing the construction either from the top of the primary (permanent bridge) or a temporary and advancing structure.
7. SPMT stands for “Self Propelled Modular Transporters” which are moving machines with many axels and degrees of freedom capable of moving and lifting in place extremely heavy objects such as an entire bridge spans.
