PINE ROAD OVER PENNYPACK

CREEK

Senior Design Team 26:

Matan Alexander, Steven Kreeley, Derek Zaccheo, Gary Reiff, and Cassandra Pruefer

Technical Advisors: Dr. Emin Aktan, Mr. Benjamin Cohen, EIT

80’

Advisor: Dr. Ivan Bartoli

Overview

⦿Problem Statement

⦿Community Impact

⦿Current Conditions

⦿Modeling

⦿Alternatives

● Bridge Rehabilitation

● Bridge Replacement

⦿Budget

⦿Life Cycle Cost Assessment

⦿Design Schedule

2

Problem Statement ⦿ Working with Streets Department

⦿ Load reduction

⦿ Emergency retrofit

⦿ Consideration of different alternatives

⦿ Recommend efficient long term solutions

3

4

Project Location

Drexel University

Bridge Location

Central

Northeast

Upper Far

Northeast

Project Location

Project Location

Background - Structural Description

5

⦿ Single 80 foot span

⦿ Two traffic lanes

⦿ 44 foot wide roadway

⦿ 8° roadway skew

⦿ Northeast-southwest orientation

Community Impact-Growth ⦿ Plans to increase public transit

⦿ Plans for commercial revitalization

⦿ Goal of alleviating traffic congestion

⦿ Current heavy use of bus

⦿ Population growth due to conversion of single to multi-family

homes

6

Project

Location

Community Impact-Detour*

7

Project

Location

*Official detour route confirmed by Philadelphia District Traffic Engineer (DTE)

8

Current Conditions - City Inspection

Rating of 4 and below requires immediate action

Current Conditions - Deck

⦿ Concrete bridge deck

⦿ Spalling and potholes

⦿ North joint in poor condition

9

Current Conditions - Girders

⦿ Eight W33X130 A-588

weathering steel

girders

⦿ Girder section loss

⦿ Girder repair

⦿ Rusting of cross

braces & bearings

10

Current Conditions - Substructure

⦿ South abutment:

minor deterioration

⦿ North abutment:

● Pedestal

deterioration

● Drainage issue

● Emergency

retrofit

⦿ Settlement of 2”

11

Existing Modeling

⦿Application of loads and load cases

⦿Existing condition

⦿Results

● Approximate 50 ton existing capacity

Deflection: L/600

Stress

12

Alternatives

13

Bridge Rehabilitation - Girders ⦿ Use of ⅜” plates to reinforce webs

⦿ Use of 5” x 5” X ⅜” angles to reinforce flange

⦿ Connected using bolts

14 City of Philadelphia repair: Plates added to

existing girders during emergency retrofit

Bridge Rehabilitation - Abutment

15

BACKWALL

PEDESTAL

ABUTMENT

Bridge Rehabilitation - Abutment

⦿ Remove pedestals and top of abutment

⦿ Replace using new pedestals and remove drainage trough

⦿ Provide sloping to drain off front of abutment

16

Bridge Rehabilitation - Joint & Bearings

⦿ Issues with leakage

⦿ Replace compression joint

⦿ Replace bearings in-kind

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ABUTMENT

BACKWALL

Bridge Rehabilitation- Deck

Repair spalling on underside of deck

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Bridge Replacement

⦿Hydrology and hydraulics (H&H)

⦿Prestressed concrete beams

⦿6 beam configuration

⦿Utilities attachment

⦿Transportation

19

Bridge Replacement - H&H ⦿ Analyzed 100 yr Design Storm

⦿ HY-8

⦿ Lift low chord 6”

20

21

Bridge Replacement - Material Considerations

Proposed: Prestressed Concrete Current: Weathering Steel

⦿ Forms patina

⦿ Poor performance

under wet conditions

⦿ Not recommended in

areas with excessive

moisture greater than

60% of the time

⦿ Performs better

under wet

conditions

⦿ Low maintenance

⦿ Less expensive

than weathering

steel

Bridge Replacement - 6 Beams ⦿ PSLRFD

⦿ Fewer beams - reduced cost

⦿ 48” wide top flange

⦿ 8” deck

⦿ Sidewalks and barriers to current standards

22

Bridge Replacement - Utilities ⦿ 20” water main

⦿ 8 supports, every 10 feet

⦿ Designed per PennDOT standards

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Bridge Replacement - Transportation

⦿ Raising top of deck 1’

⦿ 0.75% slope along roadway

⦿ 0.50% transverse slope

⦿ High point 10’ south of bridge

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Proposed Modeling

⦿Similar loads and load combinations

⦿Results - Design Check PSLRFD

● Exceeds current standards

Deflection: L/600

Stress

25

Construction Budget

26

Cost of all alternatives

Do Nothing Repair Rehabilitation Replacement

$ 0 $ 551,000 $ 968,000 $ 1,600,000

*Do nothing option does not include cost of bridge failure and maintenance

*

Design Budget

27

Life Cycle Cost Assessment

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⦿ Determined needs based on maintenance records

⦿ Evaluated by net present worth

⦿ Recommend the following for future maintenance:

● Use angle irons in place of steel plates when possible

Potentially “frame” area of interest

● Continue use of macropoxy paint system

Design Schedule

29

Conclusion

⦿Bridge is necessary for community

⦿ Inspected causes of deterioration

⦿Proposed rehabilitation and replacement

alternatives

● Return bridge to state of good repair

⦿Existing and proposed model

⦿Evaluated life cycle cost assessment

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QUESTIONS?

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Appendix

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Geotechnical Analysis

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⦿Well-drained silt loam on both sides

⦿CL soil classification

⦿Groundwater table far below elevation

⦿Piles assumed as driven

⦿Coefficients from Meyerhof deep

foundation table

⦿Based on group capacity

⦿Based on group settlement

8 - Beam Configuration

34

⦿80’ long

⦿8” Deck

⦿36” Top Flange

Peak Flow Rates

35

Hydrologic Analysis

36