2006 ASCE Florida Section Annual Conference IMPLEMENTATION OF O-CELL IMPLEMENTATION OF O-CELL ® ® LOAD LOAD TESTING FOR DRILLED SHAFTS TESTING FOR DRILLED SHAFTS AND AND AUGERED-CAST-IN-PLACE (ACIP) AUGERED-CAST-IN-PLACE (ACIP) PILES PILES John Hayes John Hayes , Senior Project Manager | LoadTest, Inc. , Senior Project Manager | LoadTest, Inc. Matthew E. Meyer, P.E. Matthew E. Meyer, P.E. , Senior Associate | Langan , Senior Associate | Langan Engineering and Environmental Services, Inc. Engineering and Environmental Services, Inc.
53
Embed
O-CELL® LOAD TESTING FOR DRILLED SHAFTS AND ACIP PILES
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
2006 ASCE Florida Section Annual Conference
IMPLEMENTATION OF O-CELLIMPLEMENTATION OF O-CELL®® LOADLOAD TESTING FOR DRILLED SHAFTS TESTING FOR DRILLED SHAFTS
AND AND AUGERED-CAST-IN-PLACE (ACIP) AUGERED-CAST-IN-PLACE (ACIP)
PILESPILES
John HayesJohn Hayes, Senior Project Manager | LoadTest, Inc., Senior Project Manager | LoadTest, Inc.Matthew E. Meyer, P.E.Matthew E. Meyer, P.E., Senior Associate | Langan , Senior Associate | Langan Engineering and Environmental Services, Inc.Engineering and Environmental Services, Inc.
2006 ASCE Florida Section Annual Conference
IMPLEMENTATION OF O-CELL LOAD TESTING FOR IMPLEMENTATION OF O-CELL LOAD TESTING FOR DRILLED SHAFTS AND AUGERED-CAST-IN-PLACE DRILLED SHAFTS AND AUGERED-CAST-IN-PLACE
(ACIP) PILES(ACIP) PILES
• Comparison of Conventional Top Load and Comparison of Conventional Top Load and the Osterberg Cell the Osterberg Cell
• O-Cell EvolutionO-Cell Evolution• Limitations and AdvantagesLimitations and Advantages• ApplicationsApplications• Constructability IssuesConstructability Issues• ACIP piles – Necessity leads to InnovationACIP piles – Necessity leads to Innovation• ACIP MilestonesACIP Milestones• InstrumentationInstrumentation
2006 ASCE Florida Section Annual Conference
COMPARISON OF O-CELL AND COMPARISON OF O-CELL AND CONVENTIONAL TESTSCONVENTIONAL TESTS
2006 ASCE Florida Section Annual Conference
O-Cell Evolution O-Cell Evolution
Evolution of Technology from 1980’s to 2006 Evolution of Technology from 1980’s to 2006
• Pioneering research by Dr. Jorj Osterberg and Pedro Pioneering research by Dr. Jorj Osterberg and Pedro De Silva in the 1980’sDe Silva in the 1980’s
• Osterberg’s impetus - to ascertain the bearing Osterberg’s impetus - to ascertain the bearing capacity within a rock socketcapacity within a rock socket
• Mid-west US and BrazilMid-west US and Brazil• Loadtest Inc. founded in 1991Loadtest Inc. founded in 1991• O-Cells available in sizes ranging from 9” – 34” dia O-Cells available in sizes ranging from 9” – 34” dia
and loads from 200 kips to >64,000 kipsand loads from 200 kips to >64,000 kips• Multi-cell and Multi-level applicationsMulti-cell and Multi-level applications• Bi-directional testing is used globallyBi-directional testing is used globally
• Maximum load limited by weaker of end bearing or skin friction
• Test results need interpretation
• Top of the pile is not structurally tested
• Top load movement curve must be calculated
2006 ASCE Florida Section Annual Conference
53
33
4
10
11
10
2
13 15
10
36
319
24
1223
17
89
157515
2
12
13
4(NH) 1
(CT) 7
Total USA Tests: 677
(MA) 26
7
2
World record load test set in 2001
(PR) 29
2 Lateral
4
(HI) 34
19(NJ) 31
(MD) 8(DC) 7
(RI) 4
Osterberg Cell Tests Completed in the United States*
*As of September 30, 2005
1
World record load test set in 2003
2
2006 ASCE Florida Section Annual Conference
O-cell Tests World-wideO-cell Tests World-wide
1-1011-2021-30>30
0
Upcoming/In progress
Key
2006 ASCE Florida Section Annual Conference
3000 ton Conventional3000 ton Conventional2500 ton Conventional2500 ton Conventional
3000 ton O-cell Test3000 ton O-cell Test
No reaction system required
Advantage in many in-situ scenarios including:
off-shore•low concrete cut-offs•confined areas
2006 ASCE Florida Section Annual Conference
One Raffles Quay, SingaporeOne Raffles Quay, Singapore(with Gammon Skanska and Meinhardt consultant)(with Gammon Skanska and Meinhardt consultant)
13 tests completed during November and December 2004 – 13 tests completed during November and December 2004 – extremely difficult soil conditions (Boulderly Clay)extremely difficult soil conditions (Boulderly Clay)
Constructability Issues For O-Cell Constructability Issues For O-Cell Installation in Drilled ShaftsInstallation in Drilled Shafts
• O-Cell diameter to shaft diameterO-Cell diameter to shaft diameter• O-Cell positions and tremie pipe positionO-Cell positions and tremie pipe position• Concrete slump and slump loss vs. timeConcrete slump and slump loss vs. time• Concrete cover on reinforcing cageConcrete cover on reinforcing cage• Spacing between vertical and horizontal Spacing between vertical and horizontal
reinforcing steelreinforcing steel• Horizontal assembly and cage liftingHorizontal assembly and cage lifting
… record static load test achieving 62,700 kips (278 MN) on a single 118-inch (3m) diameter foundation pile at the Incheon 2nd Link project in Korea…
2006 ASCE Florida Section Annual Conference
O-Cell Development to ACIP Pile O-Cell Development to ACIP Pile Construction TechniqueConstruction Technique
Necessity is the Mother of InventionNecessity is the Mother of Invention-Plato-Plato
Necessity:Necessity:• To economize the testing of ever increasing ACIP pile depth and diameter To economize the testing of ever increasing ACIP pile depth and diameter
• As pile design load increases, testing becomes more costlyAs pile design load increases, testing becomes more costly• O-cell does not require reaction system, no need to drill reaction pilesO-cell does not require reaction system, no need to drill reaction piles• 2,000 kip load test from the surface becomes difficult – e.g. - 2,000 kip load cells are 2,000 kip load test from the surface becomes difficult – e.g. - 2,000 kip load cells are
not readily availablenot readily available• Shorten time for testing – 3x design allows quick test ASTM 4311D standardShorten time for testing – 3x design allows quick test ASTM 4311D standard
Issues Faced:Issues Faced:
• Insertion of reinforcing steel through grouted shaft with O-cell attachedInsertion of reinforcing steel through grouted shaft with O-cell attached• Grout fluidityGrout fluidity• Sufficient cage weightSufficient cage weight• Acceptable O-Cell/ACIP pile diameter ratio – would 50% of available volume be the limit?Acceptable O-Cell/ACIP pile diameter ratio – would 50% of available volume be the limit?• Vertical vs. horizontal assembly (cage bending/racking)Vertical vs. horizontal assembly (cage bending/racking)• Early recognition that entire assembly had to be as straight as possibleEarly recognition that entire assembly had to be as straight as possible• O-Cell to reinforcing cage connection (steel fins vs. traditional plates) O-Cell to reinforcing cage connection (steel fins vs. traditional plates) • Augercast contractors would not change installation technique to suit our method – time Augercast contractors would not change installation technique to suit our method – time
consuming, inefficient (e.g. - more than one crane)consuming, inefficient (e.g. - more than one crane)• InnovateInnovate
• 24-inch-diameter, 100-ft long piles24-inch-diameter, 100-ft long piles• 16-inch diameter O-cell (2800 kip cap.)16-inch diameter O-cell (2800 kip cap.)
• 30-inch-diameter, 120-ft long piles30-inch-diameter, 120-ft long piles• 21-inch diameter O-cell (4800 kip cap.)21-inch diameter O-cell (4800 kip cap.)
• 36-inch-diameter, 120-ft long piles36-inch-diameter, 120-ft long piles• Multi-level assembliesMulti-level assemblies• Two 21-inch diameter O-cellTwo 21-inch diameter O-cell• 26-inch? (7200 kip cap.)26-inch? (7200 kip cap.)
2006 ASCE Florida Section Annual Conference
Milestones of utilizing O-cell Milestones of utilizing O-cell Technology in Augercast pilesTechnology in Augercast piles
• Incremental records of total load on an ACIP pile – from Incremental records of total load on an ACIP pile – from 2,400 kips to >10,000 kips2,400 kips to >10,000 kips
• Increased O-Cell/shaft diameter ratio from 0.53 to 0.70Increased O-Cell/shaft diameter ratio from 0.53 to 0.70• First multi-level test on an ACIP pile (able to separate First multi-level test on an ACIP pile (able to separate
strata)strata)• Testing some of the deepest ACIP piles worldwide - >145 Testing some of the deepest ACIP piles worldwide - >145
ft. (44 m)ft. (44 m)• Method allows economical testing at 3 times design, Method allows economical testing at 3 times design,
allowing “quick test” standard.allowing “quick test” standard.• Largest known total load applied to an ACIP pile - 10,421 Largest known total load applied to an ACIP pile - 10,421
kipskips
2006 ASCE Florida Section Annual Conference
ACIP Pile O-Cell and Reinforcing ACIP Pile O-Cell and Reinforcing CageCage
2006 ASCE Florida Section Annual Conference
Multi-level Multi-level O-cell O-cell ACIP ACIP
placementplacement
2006 ASCE Florida Section Annual Conference
Schematic of Schematic of InstrumentationInstrumentation• Dial gauges for top of Dial gauges for top of
shaft deflectionshaft deflection• Strain gauges for load Strain gauges for load
distributiondistribution• Top of cell telltales for Top of cell telltales for
for downward for downward movement and/or O-cell movement and/or O-cell expansionexpansion
• ECT’s at tip of stinger to ECT’s at tip of stinger to measure toe movement measure toe movement
2006 ASCE Florida Section Annual Conference
O-cell O-cell Test Set upTest Set up
2006 ASCE Florida Section Annual Conference
Implementation of O-Cell Load Testing Implementation of O-Cell Load Testing for Drilled Shafts and Augered Cast-in-for Drilled Shafts and Augered Cast-in-
Place (ACIP) PilesPlace (ACIP) Piles• Drilled shaft load test resultsDrilled shaft load test results• ACIP pile load test resultsACIP pile load test results• Top load test results vs. calculated equivalent top load Top load test results vs. calculated equivalent top load
curvescurves• Load DistributionLoad Distribution• Mobilized side shear for drilled shaftsMobilized side shear for drilled shafts• Mobilized end bearing for drilled shaftsMobilized end bearing for drilled shafts• Strain gauge interpretation (drilled shafts and ACIP Strain gauge interpretation (drilled shafts and ACIP
procedureprocedure• Pile diameterPile diameter• Pile undulationsPile undulations• Conditions at test shaft/pile location vs. Conditions at test shaft/pile location vs.
site subsurface conditionssite subsurface conditions
2006 ASCE Florida Section Annual Conference
Shaft CaliperShaft Caliper
2006 ASCE Florida Section Annual Conference
Shaft DiameterShaft DiameterShaft Caliper Sample Test ResultsShaft Caliper Sample Test Results
Shaft Sampling and Inspection Tools:Shaft Sampling and Inspection Tools:Sidewall SamplerSidewall Sampler
2006 ASCE Florida Section Annual Conference
Shaft Sampling and Inspection Shaft Sampling and Inspection Tools: Mini-SIDTools: Mini-SID
2006 ASCE Florida Section Annual Conference
Caliper Results from ACIP PileCaliper Results from ACIP Pile
• No technique presently available to No technique presently available to determine diameter versus depth of determine diameter versus depth of ACIP pileACIP pile
• Inferences available based on grout Inferences available based on grout factorfactor
• Reaction above and below O-Cell is Reaction above and below O-Cell is necessary to facilitate testingnecessary to facilitate testing
• Proper positioning to evaluate single Proper positioning to evaluate single or multiple bearing layersor multiple bearing layers
• Proper positioning to evaluate end Proper positioning to evaluate end bearing alone or through bearing alone or through instrumentationinstrumentation
2006 ASCE Florida Section Annual Conference
Typical Application in South FloridaTypical Application in South Florida
2006 ASCE Florida Section Annual Conference
Typical Application in Northern Typical Application in Northern FloridaFlorida
2006 ASCE Florida Section Annual Conference
Typical Application in Western Typical Application in Western FloridaFlorida
2006 ASCE Florida Section Annual Conference
ConclusionsConclusions
• Full-scale load testing of production sized Full-scale load testing of production sized foundation elements is viablefoundation elements is viable
• Can separate shaft capacity into Can separate shaft capacity into componentscomponents
• Understanding of load distribution with Understanding of load distribution with depth and available side shear with depthdepth and available side shear with depth
• Can obtain end bearing values at various Can obtain end bearing values at various deflectionsdeflections
• Adaptation of existing technology has Adaptation of existing technology has allowed ACIP piles to be O-Cell load testedallowed ACIP piles to be O-Cell load tested