MLK CONNECTOR - Pages MWGC... · 2019. 9. 26. · PROJECT OVERVIEW •Total Replacement of existing ~60 year old Martin Luther King Bridge Approach (“MLK Connector”, Existing

MLK CONNECTOR LARGE DIAMETER PILE REPAIR

Presented by

Brad Hessing & Heather Shoup

Midwest Geotechnical Conference, September 17-19, 2019 1

PRESENTATION OVERVIEW

•Installation of Large Diameter Open-Ended Pipe Piles (LDOEP) at the Piers for the New Martin Luther King Connector Bridge in East St. Louis.

•Upon construction of Pier 3, one of its piles was damaged during driving.

•Numerous solutions were considered to resolve the issue.

• A repair plan was chosen, implemented, and the problem was resolved.


PROJECT OVERVIEW

•Total Replacement of existing ~60 year old Martin Luther King Bridge Approach (“MLK Connector”, Existing Structure Number 082-6003) in East St. Louis, Illinois.

•The existing 15-Span structure consists of a 250’ long Steel Through Truss with multiple Curved Steel Girder Approach Spans.

•The new structure will be a 1286’ long 5-Span 96” deep Plate Girder Bridge with Pile Bent Abutments supported by H-Piles to Rock and Open Pile Bent Piers made up by Large Diameter Open-Ended Pipe Piles (LDOEPs) to Rock.

•New MLK Connector Bridge will carry traffic over relocated Illinois Route 3, Missouri Avenue, various R.R. tracks, and Interstates 55 and 64.


PROJECT OVERVIEW

•Proposed IDOT Structure Number: 082-0374

•Route: FAP 799

•Section 1BR-1-1

•County: St. Clair

•Contract Number 76G39


MLK CONNECTORSITE LOCATION

City of East St. Louis (St. Louis Metro East Region)

St. Clair County, Illinois

IDOT District 8

Midwest geotechnical conference, September 17-19, 2019 5

PROJECT OVERVIEW

•Each Open Pile Bent Pier (Piers 1-4) comprised of 4 Large Diameter Open-Ended Pipe Piles (LDOEPs) driven to Rock.

•All LDOEPs are 48-in Dia. with ¾-in wall thickness.

•All piles to be driven to rock to a Nominal Required Bearing of 3006 kips with a Factored Resistance Available of 1954 kips.

•All piles driven with Wave Equation (WEAP) with PDA Testing.


PROJECT OVERVIEW

•All piles are to be equipped with shoes.

•Axial Capacity includes components of both Side Resistance and End Bearing.

•No geotechnical losses were included in the design.

•LDOEPs are to be filled with concrete to a minimum of 35 ft below ground elevation. Any material that may encroach above the proposed bottom of concrete inside the pipe shall be removed prior to filling.


PROJECT OVERVIEW

WHY LDOEPs ?


BACKGROUND-PIER FOUNDATION TREATMENTS

FOUNDATION TREATMENTS CONSIDERED:

•Driven Metal Shell (Friction) Piles

•H-Piles Driven to Rock

•Drilled Shafts with Rock Sockets

•Large Diameter Open-Ended Pipe Piles (LDOEPs) Driven to Rock



METAL SHELL (FRICTION) PILES AND H-PILES DRIVEN TO ROCK

•The required number of metal shells or H-Piles would be considerably greater than

that required for either drilled shafts or LDOEPs since one drilled shaft or one LDOEP

can be substituted for a number of piles.

•Metal shells and H-Piles both would require footings; along with the number of piles

required, this would create and require a much larger “footprint” than the other two

treatment types.



METAL SHELL (FRICTION) PILES AND H-PILES DRIVEN TO ROCK (CONTD.)

•Along with taking up more space, pile supported footings would also require

temporary soil retention adjacent to IL-3 and the railroads.

•Although metal shells and H-Piles are technically feasible, due to limited

space, interferences with existing foundations, shoring requirements for IL-3

and the railroads, and additional utility and deep well conflicts, they were not

considered favorable treatments for the interior bent locations.



DRILLED SHAFTS WITH ROCK SOCKETS

• Drilled Shafts can be designed as an open pile bent and would not require a

footing or soil retention.

•Considerably less drilled shafts would be required than conventional piles.

•However, shafts were less economical and would take longer and more effort

to construct than LDOEPs.



LARGE DIAMETER OPEN-ENDED PIPE PILES (LDOEPS)

•LDOEPs can be designed as an open pile bent and would not require a

footing or soil retention.

•Considerably less LDOEPs would be required than conventional piles.

•Construction issues common to drilled shafts can be avoided since they are

driven and not drilled.

•They are more economical and faster and easier to construct than drilled

shafts.


BACKGROUND-FINAL SELECTION OF LDOEPS

FINAL SELECTION OF LDOEPS WAS BASED ON:

•Its advantages over the other treatments as previously discussed above

•Being the most economical and efficient foundation design

•Overall Constructability

•Heavily favored by IDOT District 8 (recently used on nearby structure)


BACKGROUND-SUBSURFACE DATA

•The subsurface at Pier 3 generally consists of a sequence of sandy fill,

clay, sand, and cobbles and gravel overlying sandstone and limestone

bedrock.

•The top of rock is on average approximately 120 feet below ground

surface.

•Boring data for Pier 3 is supplied by Boring BB-304.



5

EAST ABUTMENT

WEST ABUTMENT

#1 #2#3

#4

PROJECT OVERVIEW (CONTD.)

•Project was let in June of 2018 and is currently under construction.

•During Pile Driving at Pier 3, Pile 4 was crushed at its toe (OUCH!!!).

•As a result, the axial capacity of Pile 4 was compromised.

•Consequently, this problem needed to be resolved in a timely manner!

LET’S NOW TALK CONSTRUCTION AND THE FIX………


CONSTRUCTION …


ASTM A252 Grade 3 steel

50 ksi min. yield strength

45 ksi max allowable driving stress (90%)

48-in OD

0.75 inch wall thickness

Drive shoes

2 planned splices


THE PILES

THE HAMMER:

Hammer: APE D160-42

Single acting diesel

397 kip-ft rated energy max at fuel setting,

35.28 kip ram weight

11.25 ft max rated hammer stroke


WEAP ANALYSIS SUMMARY

Drivability Analysis:Assesses Driving Conditions with depth

Assessed both with and without soil plug

Bearing Graph Analysis

Did not use API method because of experience with the adjacent MLK Connector LDOEPs

Max fuel setting 4 modeled

Hammer modeled with 80% efficiency

Boring used BB-301 (W. Abut & Pier 1)

Limestone bedrock assumed 2,500 ksf unit end bearing

Full soil plug not expected

Partial plug simulated by increasing end area linearly from no plug at top to 50% plug at bottom in dense granular layer just above the bedrock surface.


WEAP DRIVABILITY ANALYSIS SUMMARY

Max 10 bpi (IDOT spec.)

11 bpi at 9.7 ft stroke (no plug)

19 bpi at 9.4 ft stroke (partial plug)

8 bpi at 9.8 ft stroke (Bearing Graph Analysis)

31 – 35 ksi estimated driving stresses

Average Transfer Efficiency is 39% (COV = 26) for diesel hammers (Appendix B3 of the 2010 version GLRWEAP manual)


PDA TESTING TIMELINE FOR DRIVING PIER 3 ON 11/27/18

10:44 am

15:25 pm

24:46 pm

33:07 pm

4



Pier 3, Pile 1, EOID

PLAY BACK OF PDA RECORD FOR PIER 3, PILE 4


DRIVE TIMELINE VIEWED IN PDA RECORD



Blow 339: Just prior to

stopping the hammer

3:15:54 pm


Blow 339: F2 Strain Sensor Wiggly


Restart Driving: Blow 348

3:19:52 pm


Blow 349: Velocity Bump Starts

3:19:53 pm


Blow 385: Velocity Bump

3:20:54 pm


Blow 450: Initial return

shifted to left

It should be here!

3:25:21 pm

45


3:30:05 pm

Midwest Geotechnical Conference, September 17-19, 2019

WELL, THAT DIDN’T GO AS PLANNED!


Pile is damaged, but the show must go on …

Moved to Pile 3 and lowered the fuel setting to 1.

PIER 3 PILE STATS

Pile No.

Nominal Required

Bearing (Kips)

CAPWAP Total

Driven Bearing

(Kips)

CAPWAP Shaft/ End

Bearing(Kips)

LP (ft) Damage Depth 1st

Indicated (ft)

Final Penetration

(blows/in.)

PDA Calc.

CSB (ksi)

PDA Calc.

ETR%

Stroke(ft)

Fuel Setting

1 3006 4,200 400 / 3,800 117.75 13 @ 1 in 42.85 55.8% 11.7 4

2 3006 4,330 630 / 3,700 117.94 15 @ 1 in 34.09 33.9% 8.4 1

3 3006 4,310 710 / 3,600 118.17 10 @ 3/8in 36.00 40.6% 9.0 1

4* 3006 495 495 / --- 123.0 118.78 54 @ 1 in 39.14 61.1% 11.2 4


* Pile 4 damaged about 5 ft above the bottom. Only use shaft resistance above damage.

PILE IS DAMAGED: NOW WHAT?

• What was the cause?

• Review Soil Borings

• Review WEAP analysis

• Review PDA files

• Review PDA/CAPWAP Report

• Can the pile still be used?

• How can it be fixed?

50

Meetings

Emails

Calls

Midwest Geotechnical Conference, September 17-19, 2019

FHWA REVIEW OF THE DAMAGED PILE IN THE MLK BRIDGE

Reviewed project documents, mainly GRL documents for the damaged Pile 4 of Pier 3 and FHWA’s findings, conclusions, and recommendations for this pile are listed next.

Damage at the toe of the pile is indicated, but extent of the damage is not clear.

Blow count and PDA capacity for the damaged pile kept increasing with depth and reached 2800 kips when driving stopped.

CAPWAP capacity results were reported for all Pier 4 piles except damaged Pile 4. (no end bearing or side resistance along damaged area)

Analysis results for the damaged pile show CAPWAP capacity of 2520 kips.

The required capacity for each pile in Pier 3 is 3006 kips. The capacity of the damaged Pile 4, 2520 kips, is close to the required capacity.


FHWA REVIEW OF THE DAMAGED PILE IN THE MLK BRIDGE

A pile cap will tie the 4 piles in Pier 3 together to function as a group of piles in supporting the pier loads.

Total capacity of four piles in Pier 3 is 15,360 kips larger than required capacity of 12,024 kips.

Conclusions/Recommendations:

Although Pile 4 in Pier 3 is damaged to some extent, it is still has good capacity, that will be supplemented if needed by capacity of neighboring piles.

Review FHWA findings and recommendations in the assessment process.


WHO NEEDS TO BE INVOLVED IN THE FIX?

• Solution Path: IDOT allowed the

Contractor to hire Structural

Engineer of Record to assess

and develop a repair

IDOT

ContractorStructural

Engineer of Record


REPAIR OPTIONS:

DO NOTHING

• Accept and move on (Contractor's 1st choice)

• Load test

Use residual capacity

• 495 kips skin• Neglect end

bearing

Make it a drilled shaft

• Drill 3' Dia rock socket

• Pressure grout bottom

Pull and Replace

Dive more piles

• Adjacent• In the center• Bigger one

around it


?

CONTRACTOR DECIDES TO CORE THE BEDROCK INSIDE THE DAMAGED PILE


PILE

CORING LOCATIONS

REPAIR OPTIONS

DO NOTHING

• Accept and move on (Contractor's 1st choice)

• Load test

Use residual capacity

• 495 kips skin• Neglect end

bearing

Make it a drilled shaft

• Drill 3' Dia rock socket

• Pressure grout bottom

Pull and Replace

Dive more piles

• Adjacent• In the center• Bigger one

around it

Drive a 60-in Dia LDOEP around the 48-in Dia Pile


PROPOSED REPAIR FOR PIER 4 SHOWING SHEAR STUD ARRANGEMENT ALONG SPLICE ZONE

48” φ Pile with rebar cage (Typical at all Piers) prior to repair

Pier 3, Pile 4 repair showing Outer 60” φ Pile and Inner 48” φ Pile with rebar cage along Splice Zone with “Interlocking” Shear Studs


REPAIR CONSTRUCTION MONITORING

•IDOT D8 Construction performing visual on blows/ft and blows/in

•PDA testing (GRL & IDOT)• Double the accelerometers and strain sensors

•Wireless (GRL)

• Cabled (IDOT)

•CAPWAP results


PDA AND CAPWAP


Nominal Required: 3,769 kips

CAPWAP Capacity: 3,733 kips

• Shaft Resistance: 1,113 kips

• End Bearing: 2,620 kips

THANK YOU

BRAD [email protected]

HEATHER [email protected]


Documents

MLK CONNECTOR - Pages MWGC... · 2019. 9. 26. · PROJECT OVERVIEW •Total Replacement of existing ~60 year old Martin Luther King Bridge Approach (“MLK Connector”, Existing