Cone penetration test based design and quality control of ... · Soil improvement design 5800...

Cone penetration test based design and quality control of soil improvement works

Zayed City, Emirati Neighbourhood Package 4, Abu Dhabi

23-Aug-18 Presentation 1

Contents

01 Menard

02 Soil Improvement Concepts

03 Cone Penetration Test & SBT

04 Soil Improvement Design

05 Case Study Abu Dhabi

Menard• Founded in 1960s• Subsidiary of Soletanche Freyssinet Group, specialist division of

Vinci Group (40.2 Billion EUR Turn Over in 2017).• Design & build ground improvement specialist contractor• Market leader in the world of soil treatment

23-Aug-18 Presentation

3

Permanent offices

Project basis

Soil Improvement – Why?


4

Bearing Capacity

Absolute Settlement Differential Settlement

Liquefaction Remediation

Soil Improvement – Why?


5

Why ground Improvement

?

Global solutions to

multiple problems

Time Savings~30-50%

Costs Savings~20-30%

Soil ImprovementApproachWhat? Requirements Soil performance

o Structureo Behaviouro Depth of improvement


6

How? Compaction Reinforcement Consolidation

Soil ImprovementRequirementsParameter requirements Density Degree of compaction


7

Functional requirements Settlement

o 20.0 mm (w/o long term)o For 3.0 m x 3.0 m footing

under 150 kPa load

Bearing Capacity

Factor of safety against liquefactiono Magnitude M = 6.0

earthquake with PGA = 0.15g at rock level.

Soil PerformanceCone Penetration Test (CPT) Geotechnical engineering properties and stratigraphy of the soil Accurate, repeatable & cheap Well established theory


8

Soil PerformanceCPT: Structure and Behaviour


9

Soil PerformanceCPT: Requirements / Performance


10

Treatment TechniquesChoosing the most efficient technique based on requirements and existing soil performance

Most important limitations are: Soil type and

behavior Depth of treatment


11

Treatment TechniquesRapid Impact Compaction (RIC) Low energy amplitude, high frequency Shallow zone of influence Fast and cheap


12

~4m

Treatment TechniquesDynamic Compaction (DC) High energy amplitude, low frequency Deep zone of influence


13

~8m

Treatment TechniquesDynamic Compaction (DC)


14

Treatment TechniquesDynamic Replacement (DR) Used to reinforce non-compactable soil

(cohesive) with inclusions of granular fill material

Performed similar to DC Higher point energy used to drive material

inside the ground


15

4-7m

Treatment TechniquesDC vs DR


16

Treatment TechniquesStone Column (SC) AKA Vibro Replacement (VR) Rock aggregate columns usable to

reinforce most types of soil Relatively deep treatment depth


17

10/16/40m

Treatment TechniquesSC InstallationDry Bottom Feed (DBF) Better quality

Wet Top Feed (WTF) Better penetration


18

16m

40m

Treatment TechniquesOthers Vibro Compaction Roller/Impact Compaction Semi-Rigid Inclusion

o Controlled modulus columno Jet Grouting

Consolidationo Vertical Drains (+ surcharge)o Vacuum Bed


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By Mechanical Modification

COMPACTION methods

Dynamic Compaction

Vibro Compaction

By Inclusions REINFORCEMENT methods

Semi-Rigid Inclusion (cement grout etc.)

Controlled ModulusColumns

Jet Grouting Columns

Dynamic Replacement

Vibro Replacement

Natural Inclusion (sand, stone, etc.)

By Hydraulic Modification

CONSOLIDATION methods

Vertical Drains

VacuumConsolidation

Treatment TechniquesProduction parameters


21

D = √ W*H

Case StudyZayed City Package 4, Abu Dhabi

Zayed City is a key project of Plan Abu Dhabi 2030

“A livable and modern Arab capital” designed around 4 pillars of sustainability: Natural environment Economic development Cultural heritage Social Cohesion

The new seat of United Arab Emirates federal government


22

Case StudyZayed City Package 4, Abu Dhabi

The full Zayed City development spans 4,500 hectares

Menard’s scope is the ground improvement of Package 4, a 500 hectare portion of the Emirati Neighbourhood residential area

Helsinki city centre for scale


23

Case StudyRegional & general site stratigraphy


24

Case StudySite characterization / Pre-CPTTesting interval 1 CPT / 625 m2


25

Case StudyPre-treatment CPT examples


26

A B C

Case StudyPre-treatment soil performanceMain criteria: Total Settlement < 20 mm & FoS liquefaction > 1.10


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A

B

C

Case StudySoil improvement design 5800 pre-treatment CPT

Compaction techniques in granular soil (DC & RIC)

Inclusion techniques in cohesive soil (DR & SC)

Liquefaction risk mitigation with SC

Total area treated is 214 ha


28

Case StudyTypical soil improvement layouts


29

Case StudyPost-treatment quality controlPurpose is to confirm that the specified requirements are met

10000 post-treatment CPT

344 Plate load test (PLT)o To assess quality of

stone columns

48 Zone load test (ZLT)o Simulation of actual

footing behavior under design load

o Expensive


30

A BC

Case StudyPost-Treatment Soil ParametersRIC, DC & DR


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1234-2

-1

0

1

2

3

4

50 5 10 15 20 25 30

Soil Index Behavior Type (Ic)

Elev

atio

n (m

NAD

D)

Tip Resistance (MPa)

Tip Resistance (MPa)Pre-Test Tip Resistance (Mpa)B test Tip Resistance (MPa)C test Tip Resistance (MPa)Pre-Test Soil Behaviour Type Index [Ic]Ic = 2.2

1234-2

-1

0

1

2

3

4

50 5 10 15 20 25 30


Elev

atio

n (m

NAD

D)


Tip Resistance (MPa)Pre-Test Tip Resistance (Mpa)A test Tip Resistance (MPa)B test Tip Resistance (MPa)C test Tip Resistance (MPa)Pre-Test Soil Behaviour Type Index [Ic]Ic = 2.2

1234-2

-1

0

1

2

3

4

50 5 10 15 20 25 30


Elev

atio

n (m

NAD

D)


Tip Resistance (MPa)Pre-Test Tip Resistance (Mpa)B test Tip Resistance (MPa)C test Tip Resistance (MPa)Pre-Test Soil Behaviour Type Index [Ic]Ic = 2.2

Case StudyZone Load test – DR & SC


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0

5

10

15

20

25

30

35

40

45

50

Tota

l set

tlem

ent (

mm

)

zlt pre Linear (pre)

Thank you for your attentionAny questions?

Markus NapariM: +971 (0)54 305 9066@: [email protected]

23-Aug-18 Presentation 33

Cone penetration test based design and quality control of ... · Soil improvement design 5800...

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