CHEF MENTEUR BRIDGE REPLACEMENT Gumbo Engineers, Inc. Lucy Farrar, Travis Honore, Jeremy Vezina, Thomas Harrison
PRELIMINARY DESIGN Fall 2016 Semester CE 4750 Professional Issues Mr. Miles Williams
INTRODUCTION The Bridge spans the Chef Menteur pass Along US 90 Located in Orleans Parish Serves as detour route for I-10 and US 11 Secondary hurricane evacuation route Economically significant route Marine commerce
NEED FOR THE PROJECT The existing bridge was built in 1930 Rehabilitated three times since Does not meet current AASHTO & LADOTD Standards 10 foot wide lanes with 1 foot shoulders Load posted bridge Structurally deficient members Extreme scouring issues Sufficiency Rating of 36.8
NEED FOR THE PROJECT PIER REHABILITATION ISSUES STRUCTURALLY DEFICIENT MEMBERS
NEED FOR THE PROJECT NARROW LANES & SHOULDERS LOAD POSTED & LOW VERTICAL CLEARANCE
EXISTING SITE CONDITIONS BRIDGE Low-Level Swing Truss Bridge Opened more than 2000 times per year Approaches are cast-in-place concrete Two 250-foot long fixed steel truss spans One 270-foot long steel truss swing span Two 97.5-foot marine traffic channels Five piers Significant scour issues Out-of-date geometry and load capacity
EXISTING SITE CONDITIONS ROADWAY The Bridge is located on US 90 Two lane roadway East of the Bridge Four lane roadway West of the bridge 10-foot wide lanes 1-foot wide shoulders Low speed limit Low volume of traffic ADT in 2007 was 4,400 cars Level of Service B/C
EXISTING SITE CONDITIONS AREA OF INTEREST Mainly residential area A few small businesses Great importance to community Multiple marinas Economically important Fort Macomb Historical site divided by current bridge Chef Menteur pass is economically significant Vessels that pass are essential for commerce Bayou Sauvage National Wildlife Refuge
HORIZONTAL ALIGNMENTS
DETOUR ROUTE The existing bridge will be used as the detour Alignment 1 Deviates at 132+00 Connects again at 174+70.35 Alignment 2 Deviates at 106+01 Connects again at 187+81.43
PRELIMINARY REDESIGN GOALS Rural Arterial 1 Roadway (RA-1) 50 mph design speed 12-foot lanes 8-foot shoulders 75-foot vertical clearance Allowing 99.9% of vessels to pass Within $120 Million LADOTD budget
ALTERNATIVE ONE - HIGH-LEVEL FIXED ALIGNMENT 1 Approximately 200 feet away from existing bridge mainspan 75-foot vertical clearance 250-foot steel mainspan Approximately 8.5 acres of ROW needed Mainly impacting Fort Macomb, the South Shore Marina, & Hi Tide Bar Water, sewer, gas, power, and telephone lines will be displaced Allows easier connections to businesses along South side More visually intrusive Total cost of $94,426,800
ALTERNATIVE ONE - HIGH-LEVEL FIXED ALIGNMENT 1
ALTERNATIVE TWO MID-LEVEL BASCULE ALIGNMENT 1 Approximately 200 feet away from existing bridge mainspan 35-foot vertical clearance when closed Allowing 66.3% of vessels to pass Unlimited vertical clearance when open 250-foot mainspan Approximately 8.5 acres of ROW needed Mainly impacting Fort Macomb, the South Shore Marina, & Hi Tide Bar Water, sewer, gas, power, and telephone lines will be displaced Total upfront cost of $95,226,300
ALTERNATIVE TWO MID-LEVEL BASCULE ALIGNMENT 1
ALTERNATIVE THREE HIGH-LEVEL FIXED ALIGNMENT 2 Alignment 2 lessens impact on community Passes through Bayou Sauvage National Wildlife Refuge Many permitting troubles Large environmental concerns Difficult foundation systems Long bridge length Total cost of $153,147,150 Significantly over budget
COST ESTIMATION Material Cost per Square Foot Singular Costs Alternative 1 High-Level Fixed Alternative 2 Mid-Level Bascule Alternative 3 High- Level Fixed Major River Crossing $ 325.00 $ 69,875,000.00 $ 41,925,000.00 $ 111,800,000.00 Bascule Span (Mid-Level) (main span) $ 1,200.00 $ 25,800,000.00 Operator's House $ 500,000.00 $ 500,000.00 Electrical System $ 1,000,000.00 $ 1,000,000.00 Mechanical System $ 750,000.00 $ 750,000.00 Timber Fender System $ 500,000.00 $ 500,000.00 Bridge Guardrail $ 15,000.00 $ 15,000.00 MISC Heavy Abutment Scour Protection $ 750,000.00 $ 750,000.00 $ 750,000.00 $ 750,000.00 R/W Land to Purchase $ 3.00 $ 1,123,500.00 $ 1,123,500.00 $ 4,368,000.00 Removal of Steel Truss Superstructure with large piers $ 30.00 $ 37,500.00 $ 37,500.00 $ 37,500.00 Roadway Construction For Bridge Replacement $ 350,000.00 $ 350,000.00 $ 350,000.00 $ 350,000.00 Maintenance of Traffic Existing Bridge used as detour $ 500,000.00 $ 500,000.00 $ 500,000.00 $ 500,000.00 Total Cost (w/ 30% contingency) $ 94,426,800 $ 95,226,300 $ 153,147,150
EVALUATION OF ALTERNATIVES Comparison matrix utilized Larger numbers are more significant Cost Safety LADOTD Specifications Detour routes (marine & traffic) Constructability Roadway geometry Permitting Factors Considered Environmental impacts Right of Way Acquisition Utility relocation Economic impact Future maintenance Marine navigability Scour issues Aesthetics
EVALUATION MATRIX Evaluation Criteria Weight Alternative 1 Alternative 2 Alternative 3 High-Level Fixed Mid-Level Bascule High-Level Fixed Safety 10 6 10 8 Cost 10 6 8 2 Detour Routes (Marine) 8 10 3 10 Detour Routes (Traffic) 8 6 6 9 Constructability 7 8 5 4 Enviromental Impacts 8 6 6 1 Permits Required 7 5 5 2 Utility Relocations 4 4 4 7 ROW Acquisition (Acres) 5 6 6 2 ROW Acquisition (Cost) 10 6 6 2 Navigational Issues 6 9 8 9 % of Boats w/o Opening 6 9 4 9 Roadway Geometry 6 6 6 8 Channel Scour Issues 7 6 7 1 Meeting DOTD Specs 10 10 10 10 Economic Impacts to Area 8 6 7 10 Future Maintenance 9 9 3 7 Aesthetics 6 6 8 9 Weighted total 944 864 820
PREFERRED ALTERNATIVE Alternative 1 is recommended High-level fixed bridge on alignment 1 Lowest cost by far Low maintenance Good constructability Lower environmental impacts Least ROW acquisition required
FINAL DESIGN Spring 2017 Semester CE 4460 Design of Bridges Dr. Ayman Okeil, Mr. Paul Fossier
TASK BREAKDOWN Task 1 Business Letter Engineering Fees Quality Control Task 2 Design Quality Control AutoCAD Engineering Fees Task 3 Design Quality Control AutoCAD Engineering Fees Task 4 Design Quality Control AutoCAD Task 5 Design Quality Control Engineering Fees Construction Costs AutoCAD Presentation Lucy (Project Manager) Travis Thomas Jeremy Task Manager Task Manager Task Manager Task Manager Task Manager Task breakdown decided as a team Deviations from original task breakdown recorded Quality control by a team member not involved with assignment completion
DESIGN CRITERIA LADOTD Bridge Design and Evaluation Manual (2016) AASHTO LRFD Bridge Design Specifications (7 th edition with interims) AASHTO Manual for Bridge Design Evaluation (4 th edition) HL-93 Truck load with LADV-11 Multiplier
Horizontal alignment given Existing US 90 Route Vertical alignment BRIDGE LAYOUT 75 foot vertical clearance as per US Coast Guard request Consistent span lengths for straight spans Consistent span lengths for curved spans 380 foot, 3 span continuous steel plate girders for main navigational span Span to depth ratio estimated using BDEM Tables 40 foot reinforced concrete approach slabs
PRELIMINARY BRIDGE LAYOUT
PRELIMINARY BRIDGE LAYOUT
PRELIMINARY BRIDGE LAYOUT
DECK DESIGN FOR PRESTRESSED GIRDER SPAN 120 7 straight span Width of bridge = 46 6 Reinforced Concrete Rebar Strength, Fy= 60 ksi AA(M) Concrete with a strength, f c= 4.2 ksi 32 F-Shape Barrier 8.5 deck thickness including 0.5 sacrificial thickness 10 overhang Limit States Strength I Service I
PRESTRESSED GIRDER DESIGN 120 7 straight span Designed for typical interior girder Composite girder Flexural design only Limit states Service 1 Service III Strength I LG 72 Girder Prestressing Strands: 42 strands 0.6 Ø 270 ksi low relaxation Concrete: F ci = 5.8 ksi F c = 6.5 ksi
DECK DESIGN FOR PRESTRESSED GIRDER SPAN
PRESTRESSED GIRDER DESIGN
PRESTRESSED GIRDER DESIGN
STEEL GIRDER DESIGN 237 5 straight, continuous span Design for typical interior girder ASTM Grade 50W Steel Steel Strength, Fy=50 ksi Assumed full composite action between deck and girder Welded shear stud connectors spaced at 6 Designed for flexure, fatigue, and shear Limit States Strength 1 Fatigue 1I ADTT of 2,500 vehicles per day Deck designed with design tables in BDEM
SUBSTRUCTURE DESIGN Pile designed for L/D <24 STAAD Analysis Maximum moments and shears in cap Maximum pile load reactions Pile Cap Rebar designed A(M) concrete Geotechnical data given from boring sample Mainly silt and clay 4-24 square precast prestressed piles per bent 159 4 long Tipped into dense sand layer 3-point pickup
SUBSTRUCTURE DESIGN
ENGINEERING FEE ESTIMATION Manhours estimated prior to starting task Team members kept track of hours spent with Google Calendar Manhours used to calculate engineering fees in spreadsheet Hourly rate assigned based on responsibly 1.5 assumed overhead 12% assumed profit
ENGINEERING COST ESTIMATION TOTAL LABOR COSTS Estimated Manhours Actual Manhours Rate per hour Estimated Total Cost Actual Total Cost Project Manager 27 27 $ 62.54 $ 1,688.58 $ 1,688.58 Task Manager 22 28 $ 50.40 $ 1,108.80 $ 1,411.20 Designer 53 66 $ 45.00 $ 2,385.00 $ 2,970.00 Checker 36 41 $ 45.00 $ 1,620.00 $ 1,845.00 CAD Detailer 53 63 $ 23.49 $ 1,244.97 $ 1,479.87 TOTAL 191 225 $ 226.43 $ 8,047.35 $ 9,394.65 Estimated Total Cost Actual Total Cost Direct Labor $ 8,047.35 $ 9,394.65 Overhead (1.5) $ 12,071.03 $ 14,091.98 Profit 12% $ 965.68 $ 1,127.36 TOTAL FEE $ 21,084.06 $ 24,613.98
CONSTRUCTION COST ESTIMATION Quantities for spans on pile bents Ratio was used to determine quantities for spans not designed All prestressed girder spans Average bid for 2016 quarter 4 used to estimate unit costs BDEM cost estimate tables used for items with no bid data Sans 8-25 on column bents Treated as major river crossing Cost estimated using BDEM cost estimate tables Mobilization is 5% of total construction cost Bridge removal for steel truss bridge Cost estimated using BDEM cost estimate tables
CONSTRUCTION COST ESTIMATION COSTING ITEM NO. ITEM UNIT QUANTITY PRICE PRICE PER UNITRATIO MAIN NAVIGATIONAL SPAN (LG 8 to LG 25) SQ FT 111153.414 $ 36,124,859.55 325 120.583' Span 804-01-00600 PRECAST CONCRETE PILES (24") LIN FT 641.24 $ 87,535.67 136.51 1 804-12-00100 LOADING PERMANENT PILES EACH 4 $ 7,050.08 1762.52 1 CLASS A(M) CONCRETE (BENTS)(COLUMNS AND 805-02-00400 CAPS) CU YD 11.407396 $ 17,111.09 1500 1 805-04-00100 CLASS AA(M) CONCRETE CU YD 161 $ 16,100.00 100 1 806-01-00100 DEFORMED REINFORCING STEEL POUND 58617.71 $ 68,582.72 1.17 1 805-08-01700 PRECAST PRESTRESSED CONCRETE GIRDERS (LG 72) LIN FT 600.415 $ 96,066.40 160 1 4 additional 120.583' Spans 804-01-00600 PRECAST CONCRETE PILES (24") LIN FT 10259.84 $ 1,400,570.76 136.51 4 804-12-00100 LOADING PERMANENT PILES EACH 16 $ 28,200.32 1762.52 4 CLASS A(M) CONCRETE (BENTS)(COLUMNS AND 805-02-00400 CAPS) CU YD 45.629584 $ 68,444.38 1500 4 805-04-00100 CLASS AA(M) CONCRETE CU YD 644 $ 64,400.00 100 4 806-01-00100 DEFORMED REINFORCING STEEL POUND 234470.84 $ 274,330.88 1.17 4 PRECAST PRESTRESSED CONCRETE GIRDERS (LG 805-08-01700 72) LIN FT 2401.66 $ 384,265.60 160 4
CONSTRUCTION COST ESTIMATION ITEM NO. ITEM UNIT QUANTITY PRICE PRICE PER UNIT COSTING RATIO 7-107.583' Spans 804-01-00600 PRECAST CONCRETE PILES (24") LIN FT 25011.04385 $ 3,414,257.60 136.51 6.24533309 804-12-00100 LOADING PERMANENT PILES EACH 24.98133236 $ 44,030.10 1762.52 6.24533309 CLASS A(M) CONCRETE 805-02-00400 (BENTS)(COLUMNS AND CAPS) CU YD 71.24298771 $ 106,864.48 1500 6.24533309 805-04-00100 CLASS AA(M) CONCRETE CU YD 1005.498628 $ 100,549.86 100 6.24533309 806-01-00100 DEFORMED REINFORCING STEEL POUND 366087.123 $ 428,321.93 1.17 6.24533309 805-08-01700 PRECAST PRESTRESSED CONCRETE GIRDERS (LG 72) LIN FT 3749.791667 $ 599,966.67 160 6.24533309 3-89.833' Spans 804-01-00600 PRECAST CONCRETE PILES (24") LIN FT 3203.042878 $ 437,247.38 136.51 2.234966786 804-12-00100 LOADING PERMANENT PILES EACH 8.939867145 $ 15,756.69 1762.52 2.234966786 CLASS A(M) CONCRETE 805-02-00400 (BENTS)(COLUMNS AND CAPS) CU YD 25.49515118 $ 38,242.73 1500 2.234966786 805-04-00100 CLASS AA(M) CONCRETE CU YD 359.8296526 $ 35,982.97 100 2.234966786 806-01-00100 DEFORMED REINFORCING STEEL POUND 131008.6349 $ 153,280.10 1.17 2.234966786 PRECAST PRESTRESSED CONCRETE 805-08-01700 GIRDERS (LG 72) LIN FT 1341.907583 $ 214,705.21 160 2.234966786 Total $ 44,226,723.18 Total with Mobilization (5% Total Cost) $ 47,164,059.34
Preliminary Design: Multiple alternatives were considered Costs were estimated using LADOTD BDEM Alternative one preferred Total cost of $94,426,800 Well within $120 Million budget Fulfills all LADOTD design criteria CONCLUSION Task Breakdown Design Criteria Final Design: General layout of bridge Deck Design Questions? Prestressed Girder Design Steel Girder Design Pile Bent Design Engineering Fee Estimate Construction Cost Estimate