www.dotd.la.gov

Leeville To Golden Meadow Phase 2

LA 1 STATUS

Presentation Agenda

• Importance of LA 1• Overview of LA 1 Phases• Environmental Permitting/Pipelines• Overview of LA 1, Phase 2• Tentative Schedule• Phase 2B Deep Dive• Acknowledgements• Conclusion/Questions

LA 1 Critical to LOOP to support its Connection to 50% of the

Nation’s Refineries

LA 1 vital to Regional Economic Resiliency:

Planned $800M LNG Plant, Fourchon Island Shipyard

Development, LA Master Plan Restoration Projects

LA 1 is the ONLY Highway Evacuation Route for Grand Isle & Port

Fourchon

Importance of LA 1Existing highway is sinking and floods with storm surge

Overview of LA 1 PhasesPhase 1 – Leeville to Port Fourchon (Completed 2011)

8.8 miles of elevated structure (2 – 12 ft lanes with 8 ft shoulder)Construction Cost: $371,600,000

Phase 2 – Golden Meadow to Leeville8.3 miles of elevated structure (2 – 12 ft lanes with 8 ft shoulders)Estimated cost: $346,000,000

Phase 3 – US 90 to Larose 4 lanes of at-grade highway from Larose, LA to US 90 (19.5 miles)Estimated Cost: $346,000,000

Phase 4 – Parallel Structure, Golden Meadow to Fourchon15.1 miles of elevated structureEstimated cost: $660,000,000

Funding Sources

• Federal ear marks• State Bonds• Industry contribution• Gulf of Mexico Energy Security Act (GOMESA)• Tolling• Port Fourchon• LA 1 Coalition• CPRA• Lafourche Parish• Transportation Infrastructure Financing & Innovation Act

(TIFIA) Loan

Environmental Permitting

• Phase 1 permits expired in 2012. Project was fully permitted

again for Phase 2 in 2015

• A Section 408 permit was required for the South Lafourche Levee

crossing in Golden Meadow.

• End on construction utilized to minimize impacts to marsh.

• Staging areas have been selected that will provide the

opportunity to restore and create marsh upon completion of

construction- even during construction these fill areas will provide

some buffer benefits.

• Geotechnical Drilling airboat system designed and constructed to

minimize impacts to the marsh while collecting borings.

Pipelines

• Leeville is home to one of the oldest oil and gas fields in

Louisiana

• Project team met with pipeline owners and operators to

determine existing pipeline status and ownership

• Magnetometer survey and probing for existing lines

• Divers assisted with determining connectivity

• Lines that were not claimed were hot-tapped to determine

activity status

Pipeline Disposition

Description UnitPhase 2A

(H.011207)

Phase 2B

(H.011208)

Phase 2C

(H.008145)

Removal of Abandoned Pipelines Each 44 0 1

Relocation of Active Pipelines Each 7 0 0

Pipeline Protection (Non-Removal) Each 8 8 2

Well Protection Each 1 0 0

Tolling Discussion

Phase 1 toll location currently configured to accept cash and Geauxpass.

All electronic tolling ???

POSSIBLE TOLLING OPTION

PHASE 2C WITH ELECTRIC TOLLING

AND CASH LANE

Overview of LA 1, Phase 2

Phase 2A• Southernmost segment tying into

Phase 1 Structure near Leeville

• Approx. 1 mile in length, crosses Bollinger Canal

• Segment to be constructed via dredge access

• Plans approx. 90%complete

N

Phase 2B• Middle Segment

• Approx. 7 miles in length, top-down construction required

• Precast elements used for construction (piles, girders, bent caps)

• Plans approx. 75% complete

• Multiple pipelines crossed

N

Phase 2C• Northern segment near Golden

Meadow, LA

• Approx. 0.75 miles in length

• Crosses over levee, T-wall and levee improvements included in plans (Required 408 permit)

• Plans complete

N

LA 1,

PHASE 2C

CL LEVEE

N

Phase 2D

N

• At-Grade Segment in Golden Meadow, LA

• Ties elevated structure into LA 3235

• Possible location for at-grade tolling plaza

• Segment limits dependent on chosen tolling concept

Phase 2E

N

• Bridge Widening Segment in Leeville, LA

• Dredging required forconstruction access

• December 2017 Letting• Bid Award $13.2 million

Phase 2E Rendering

Phase 2B Deep Dive

• Segment is 36,316.57’ in length and ties Phase 2A (Bollinger Canal crossing) to Phase 2C (levee crossing)

• LA 1, Phase 1A as a Case History

• Top-down construction requirement

• Bid Alternatives Investigation prior to final design:

• Refined analysis of substructures

• Phase 1A required top-down construction techniques similar what is required for Phase 2B

• Phase 1A segment length was 5.3 miles in length, Phase 2B is 7.0 miles

• Construction Debrief suggested the following design refinements:• Intermediate diaphragms be

removed• Minimize use of pile batter

Phase 1A Case History

• Removal of Intermediate Diaphragms• Intent was to use LG Girders for Phase 2• Intermediate diaphragms required by BDEM due to extreme high winds• Analysis performed to determine whether intermediate diaphragms are required (155

mph design speed)• Beam type and span length consistent with span layout

• CSI Bridge and internal HNTB Structural Analysis programs used

• Results of analysis submitted to LADOTD Bridge Design Section for review and acceptance

• Removal of Intermediate Diaphragms on LG Girder spans deemed acceptable

Phase 2 Design Objectives

• Reduction of Battered Piles• Pile batter efficiently resists lateral loads• Intent to only batter in longitudinal direction along bridge CL, transverse batter to be

eliminated• Transverse lateral forces to be resisted via frame action between piles and cap

• Develop moment connection detail between piles and cap beam

• Use FB-Multi Pier to determine lateral and longitudinal force distribution in span units

Phase 2 Design Objectives

5%-10% 65%-85% 10%-15% 5%-10%

Top-Down Construction

• Requirement similar to Phase 1A

• Contractor allowed to install temporary works such as access

trestle but nothing other than permanent bridge can remain

Top-Down Construction

• Required due to estimated project cost

• 19 Value Engineering recommendations proposed, 4 required further investigationo Construct Segmental Bridge – carried into Alternatives Investigation

Reporto On-site casting plant – requires 18 acres, requires waiving PCI

certification, deemed feasible but further investigation requiredo Use LG-54 in lieu of LG-36 (increase span length) - carried into

Alternatives Investigation Report

o Increase from 24” to 30” voided piles - carried into Alternatives

Investigation Report

• Outcome of Value Engineering Workshop was Bid Alternatives Investigation Report

Phase 2B Value Engineering Workshop

• PPC Girder Alternatives (HNTB Investigation)o Alternative A1 – 65’ long typical span, four LG-36 girders, four or six 24” PPC pileso Alternative A2 – 108’ long typical span, four LG-63 girders, six 24” PPC piles

• Segmental Alternatives (Corven Engineering Investigation)o Alternative A3 – 65’ long typical span, trapezoidal box shape, four 24” PPC pileso Alternative A4 – 100’ long typical span, trapezoidal box shape, four 30” PPC pileso Alternative A5 – 136’ long typical span, trapezoidal box shape, six 30” PPC piles

• Each alternative investigated for construction means and methods

• Independent Contractor’s Style Bid Estimate developed for each alternative

Bid Alternatives Investigation

• Contractors-style estimate which includes a breakdown on labor, equipment, permanent materials and subcontractors

• Address means and methods and schedule

• Construction estimate used in-lieu of engineers estimate or using DOTD estimating tool with historical prices

• Balanced Construction Concept – Precast Bridge Elements (Girder, Precast Cap, Pile Segments) are of relatively equal weight• Allows for “proper-sizing” of construction equipment

Independent Contractor’s Style Bid Estimate

• Alternative A1 is most similar to Phase 1A construction

• BDEM and LADV-11 used

• LG-36 vs. AASHTO Type IIIo LG-36 – 4 beam lines (8.5 ksi)o Type III – 5 beams lines (8.5 ksi)o Type III – 4 beams lines (10.0 ksi)

• No intermediate diaphragms

• Four – 24” PPC piles (expansion)• Six – 24” PPC piles (fixed)

• No transverse pile batter

Alternative A1 (65’ PPC Girder)

• Started with 100’-0” to compare with Alternate A4 (100’ segmental)

• Increased to 108’-0” based onbalancing superstructure andsubstructure construction

• LG-54 vs. LG-63 girderso LG-54 - 5 beam lines (8.5 ksi)o LG-63 - 4 beam lines (8.5 ksi)

• 24” vs. 30” pileso 6 – 24” piles (Exp.), 8 – 24” piles (fixed)o 4 – 30” piles (Exp.), 6 – 30” piles (fixed)

Alternative A2 (108’ PPC Girder)

• 7 ft deep trapezoidal box

• 9’-4” segmental units

• Segments cast in on-site casting yard

• Longitudinal tendons o Fully bonded o Placed internally to the concrete webso 19 x 0.6” strands

• Transverse tendonso 3 – 4 strand tendons per segmento 3’-2” spacing

• 4 – 24” piles

• 14 acre on-site casting yard

Alternative A3 (65’ Segmental)

• 7 ft deep trapezoidal box

• 10’-0” segmental units with 6” CIP closure pours

• Segments cast in on-site casting yard

• Longitudinal tendons o Unbonded o External placement within boxo 22 x 0.6” strands

• Transverse tendonso 3 – 4 strand tendons per segmento 3’-4” spacing

• 4 – 30” piles

Alternative A4 (100’ Segmental)

• 8 ft deep trapezoidal box

• 10’-4” segmental units with 6” CIP closure pours

• Segments cast in on-site casting yard

• Longitudinal tendons o Unbonded o External placement within boxo 22 x 0.6” strands

• Transverse tendonso 3 – 4 strand tendons per segmento 3’-4” spacing

• 6 – 30” piles

Alternative A5 (136’ Segmental)

Alternative Difference in Cost DurationAlternative A1 – 65’ Span Concrete Girder Bridge: = 0% (base) (71 Months)Alternative A2 – 108’ Span Concrete Girder Bridge: = -5% (70 Months)Alternative A3 – 65’ Span Precast Segmental Bridge: = 24% (73 Months)Alternative A4 – 100’ Span Precast Segmental Bridge: = 10% (60 Months)Alternative A5 – 136’ Span Precast Segmental Bridge: = 10% (56 Months)

• Alternative A2 yields lowest total cost

• Segmental yields shortest construction duration

• Alternative Investigation Outcome• Both PPC Alternatives (A1 and A2) should advance to final design• Substructure sub-alternatives for A2 should advance to final design (6-24” vs. 4-30”)• Segmental Alternatives (A3, A4 and A5) should not advance due to cost concerns

Comparison of Alternatives

Alternative A1 (65’ typical span, four LG-36 girders, four or six 24” piles)o 4 span continuous unitso 560 total spans (547 – 65’ PPC spans with no skew, 12 – PPC skewed spans, 1 – 150’ steel

plate girder span)o 559 total bents ( 436 – 4 pile bents with no skew, 110 – 6 pile bents with no skew, 11 skewed

bents, 2 transition bents)

Phase 2B Final Design Summary

Typical Expansion Bent

Typical Fixed Bent

Alternative A2.1 (108’ typical span, four LG-63 girders, six or eight 24” piles)o 3 span continuous unitso 339 total spans ( 338 – PPC spans with no skew, 1 – 150’ steel plate girder span)o 338 total bents ( 222 – 6 pile bents with no skew, 114 – 8 pile bents with no skew, 2

transition bents)

Alternative A2.2 (108’ typical span, four LG-63 girders, four or six 30” piles)o Same superstructure as Alternative 2.1o 338 total bents ( 222 – 4 pile bents with no skew, 114 – 6 pile bents with no skew, 2

transition bents)

Phase 2B Final Design Summary

• Goal is to reduce cost and construction schedule

• Repetitive Nature of Phase 2B lends itself to precast elementso Alternate A1 – 546 of 559 bents fall into two basic substructure layouts (97.7%)o Alternate A2.1 and A2.2 – 336 of 338 bent fall into two basic substructure layouts

(99.4%)

• Pile/Cap moment connection provides better performance for lateral loads such as hurricane events, but additional forces must be resisted by cap.

• Pile loads are affected due to frame action

Refined Substructure Analysis

• Pile/cap moment connection investigationo Reinforcement cage in top of pileo Embed piles one diameter into cap

• Detailing Considerationso Provide one pile diameter embedment into cap

without substantially increasing cap depth o Provide closed stirrups over length of

pile embedment for additional confinemento Provide standard mis-driving tolerance

(3” transv. to cap, 6” long. along cap)o Provide void for embedment of battered piles

• Design Considerationso Cap – force couple from pile conn,

punching shear due to embedmento Pile – P-M interaction at bottom of

cap where P/S strands not fully developedo Bent – Trans. Deflection under Service

Eliminate Transverse Pile Batter

• Nonlinear analysis

• Soil Interaction accounted for usingspring elements acting along pile

• Site exhibits poor soil conditions,very little lateral resistance for top30’ of soil

• LADOTD determining pile lengths,provided input data for models

• Multiple iterations between globaland individual models

FB-Multipier

• Global Modelso Model entire span unito Determine distribution factors for lateral loadso Used to calibrate soil “spring” parameterso Information transferred to single bent models

FB-Multipier

• Single Bent Models• Incorporates all loads applied to bent• Loads factored and combined into

applicable limit states• Biaxial P-M interaction checks performed

at top of pile (location of reduced capacity)• Pile/cap connection moments developed• Cap design moments and shears• Pile load development for geotechs.• Confirm/calibrate bent response under

transverse loading

• Current results of modeling• Pile loads surpass geotechnical information

in some areas, limited extrapolation vs.additional piles

• Bent exhibits larger-than-expectedtransverse deflections, refinement required

• Workshop scheduled

FB-Multipier

Acknowledgements

Questions