How to Design and Build a Fence/G traverse Bridge or Graffiti Project

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2 Outline Project Location Project Description Project History Site Constraints Geotechnical Investigation & Soil Profile Foundation Design Process Photos

3 Project Location Project Limits: The Grand River east to Fuller Ave.

4 Project Description 1.75 miles of full depth road reconstruction with additional third through lane and merge weave lanes 4,000 feet of soldier pile & lagging Retaining Wall Replacement of five structure crossings: Coit Avenue over I-196 Eastern Avenue over I-196 Lafayette Avenue under I-196 Diamond Avenue over I-196 Fuller Avenue over I-196

5 Project Description Project Cost: $40 Million Schedule: Design Phase Summer 2007 Spring 2009 Bid Letting September 2009 Construction Start April 2010 Substantial Completion - November 2010

6 Project History Original freeway designed in 1962 and opened by 1964 Typical urban depressed limited access roadway Original bridges constructed as three or four span structures Substructures Pile supported abutments (40 ton CIP Concrete) and spread footing piers and abutments

7 Original Bridges Coit Avenue

8 Original Bridges Lafayette Avenue

9 Original Bridges Eastern Avenue

10 Original Bridges Diamond Avenue

11 Original Bridges Fuller Road

12 Site Constraints 130 ft. St. Isidore Church Constructed in ft

13 Photo courtesy of mlive.com

14 Site Constraints Grand Rapids Medical Mile: Van Andel Institute, Grand Rapids Community College's Calkins Science Center, Spectrum Health's Butterworth Hospital complex, Grand Valley State University's Cook-DeVos Center for Health Sciences, and Michigan State University Secchia Center Medical School

15 Photo courtesy of MDOT Grand Rapids TSC

16 Geotechnical Investigation Coit Ave., Lafayette Ave., and Eastern Ave. bridge designs began in 2006, at the beginning of when MDOT fully adopted the AASHTO LRFD Design Method. Final Geotechnical Investigation included performing borings for substructures, retaining walls, roadways, and signs. In total 17 bridge borings, 12 retaining wall borings (and 15 misc. borings (signal poles, signs, ITS) were performed over a 2 year period.

17 Generalized Soil Profiles Lafayette Bridges: Loose sand fill down to ft.± Dense to extremely dense sand to 85 ft.± (EB/south side) V. stiff to hard clay strata within similar extremely dense sand to 90 ft.± (WB/north side) Coit Bridge: Surficial sand fill down to 5 ft.± Loose to med. dense sand to 40 ft.± Alt. layers of hard clay and v. dense sand, 40 to 90 ft.±

18 Eastern Bridge: Surficial fill down to 5 ft.± V. loose to med. dense sand, increasing to med. dense to v. dense to 75 ft.± (with cobbles/boulders!) Hard clay/clayey silt to 100 ft.± Diamond Bridge: Loose to med. dense sand, transitioning to extremely dense to 100 ft.± (occ. clay layers below 50 ft.) Fuller Bridge: Loose to med. dense sand to 9 to 17 ft. ± depth Alt. sand, clay, silt, and gravel strata to 95 to 115 ft.± (occ. cobbles below 50 ft.) strength increasing with depth (extremely dense/hard)

19 Foundation Design Designed per AASHTO Load Resistance Factor Design Manual Section Preliminary Options: Driven H Piles HP14x73 at 600 kips nominal resistance HP12x53 at 400 kips nominal resistance Spread footings Service and Strength Limit State considerations Benefit of depressed freeway and prior loading

20 Foundation Selection Criteria Vibration considerations Limiting vibrations to adjacent sensitive structures 100 year old Church Medical Facilities (underground tunnels) Considerations for Shakedown Settlement (Service Limit State) Overlaying new structure footprint versus existing. Strength Limit State Looser soils with groundwater

21 Pile Foundation Design Iteration Pile Size and Maximum Nominal Pile Driving Resistance (R ndr ) selection Per MDOT Bridge Design Manual Estimate Pile Tip Depth/Elevation Per AASHTO LRFD Sec Refine Estimated Pile Tip Depth/Elevation based on structural loading Perform lateral pile analysis and determine Point of Fixity Again refine Estimated Pile Tip Depth/Elevation based on structural loading

22 Spread Footing Design Iteration Determine the Bearing Elevation of the footing Provide the Service Limit State and Strength Limit State soil pressures (preliminary design) Provide effective footing widths based on site constraints and preliminary design loading (ranges of B and associated bearing resistances). Evaluate the strength limit state of the soils per AASHTO LRFD Sec Evaluate the service limit state of the soils per AASHTO LRFD Sec

23 Specific Example Fuller Bridge & Wall Collaboration FOUNDATION SELECTION H-piles and pipe piles considered, but not preferred due to vibrations adjacent existing structure for part-width construction. Concerns with spread foundations due to loose sand soils and high groundwater at bearing elevation in some locations. Improvement options included extending footing deeper, remove and replace, or in-situ densification.

24 Soil and groundwater limitations related to both design and potential impacts during construction were discussed with the Bridge Engineer in order to design an appropriately-sized spread foundation that achieves the required resistance, minimizes differential settlement, and can also be practically constructed.

25 A spread foundation option was ultimately selected, achieved through a remove and replace operation. Where excavations encountered groundwater, large aggregate was worked into the subgrade for stabilization.

26 CONSTRUCTION ISSUES Temporary Retaining Wall for Part-Width construction Retained soil generally consisted of uniformly graded sand or sand fill (consistent with MDOT Class II or III sand gradations). Due to concerns with vibrations, a cantilever soldier pile/lagging wall system was selected.

27 RETAINING WALL ALONG I-196 URS worked closely with Somat to develop active and passive earth pressures for 4000 of soldier pile wall Large storm sewer was to be installed in front of the retaining wall after the wall was constructed. The pipe was to be located as close as 20 feet to the wall face. The pipe invert was to be situated at about 10 feet below the base of the exposed wall face. Excavation below the wall would compromise the passive resistance relied on in the retaining wall design. A temporary stabilizing berm was to be placed.

28 Conceptual Cross-Section

29 Summation Having the knowledge of subsurface conditions (or potential) during the planning/ pre-design phase has time-saving and cost-saving benefits to your project. Maintaining project-long (and open) communication between geotechnical and structural engineers is mutually beneficial.

30 Photo courtesy of MDOT Grand Rapids TSC

31 Photo courtesy of mlive.com

32 Photo courtesy of mlive.com

33 Photo courtesy of mlive.com

34 Photo courtesy of MDOT Grand Rapids TSC

35 Photo courtesy of MDOT Grand Rapids TSC

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