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1Jean Louis BRIAUD1
TEXAS A&M UNIVERSITY
Deeyvid SAEZ BARRIOS2
1. President of ISSMGE, Professor and Holder of The Buchanan Chair, Texas A&M University
2. PhD Graduate Student and Research Assistant, Texas A&M University
April 2010THEORY PRACTICE
1. Load Resistance Factors Design (LRFD) Approach
2. Site Investigation
3. Design of Shallow Foundation for Vertical Loads
4 P I
CONTENT OUTLINE
4. Pile Instalation
5. Design of Single Piles for Vertical Loads
6. Design of Pile Group for Vertical Loads
7. Design of Piles for Horizontal Loads
8. Special Cases (Shrink-Swell Soils, Downdrag andScour)
9 The Role of Load Testing9. The Role of Load Testing
10. Conclusion
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
1
2LOAD RESISTANCE FACTOR DESIGN (LRFD)
WORKING STRESS DESIGN
RL FS 2 0 3 0
LOAD RESISTANCE FACTORS DESIGN (LRFD)
= 1.0 to 2.0RL
FSL = FS 2.0 to 3.0
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
L= Load = Load Factor
R= Resistance = Resistance Factor =FS
1.0 to 2.0 = 0.30 to 0.90
RL =
IMPORTANT LOAD FACTORS IN FOUNDATION ENGINEERING
=n n iiii RL
LOAD RESISTANCE FACTOR DESIGN (LRFD)
= =i i
iiii1 1
i Li= 1.25DL + 1.75LL For Ultimate Load
i Li= 1.0DL + 1.0LL For Settlement in Sand & Immediate Settlement in Clays
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
i Li= 1.0DL Long Term Settlement in Clays
i Li= 1.25DL + EQLL+1.0EQ For Earthquake Analysis
2
3 IMPORTANT RESISTANCE FACTORS FOR SHALLOW FOUNDATION
= =
=n
i
n
iiiii RL
1 1
LOAD RESISTANCE FACTOR DESIGN (LRFD)
i R= 0.35R For Friction Angle Approach ---SANDS
i R= 0.45R For SPT Approach ---SANDS
i R= 0.55R For CPT Approach---SANDS
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
i R= 0.60R For Su Approach---CLAYS
i R= 0.50R For CPT Approach---CLAYS
Su= Undrained Shear Strength
IMPORTANT RESISTANCE FACTORS FOR DRIVEN PILESUNDER COMPRESSION LOADS
=n n RL
LOAD RESISTANCE FACTOR DESIGN (LRFD)
= =
=i i
iiii RL1 1
i R= 0.56R to 0.70R (Verif.) For Su Method---CLAYS
i R= 0.36R to 0.45R (Verif.) For SPT Method ---SANDS
R 0 44R 0 55R (V if ) F CPT M h d SANDS
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
i R= 0.44R to 0.55R (Verif.) For CPT Method---SANDS
Use 0.85(compression) for (uplift)
Su= Undrained Shear Strength
3
4 IMPORTANT RESISTANCE FACTORS FOR BORED PILESUNDER COMPRESSION LOADS.
=n n RL
LOAD RESISTANCE FACTOR DESIGN (LRFD)
= =
=i i
iiii RL1 1
i R= 0.65R For Su Method---CLAYS SIDE
i R= 0.55R For 9Su Method ---CLAY POINT
R= 0 65R For Method SANDS SIDE
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
i R= 0.55R For 0.057N Method---SANDS POINT
Use 0.85(compression) for (uplift)
Su= Undrained Shear Strength
i R= 0.65R For V Method---SANDS SIDE
1. Load Resistance Factors Design (LRFD) Approach
2. Site Investigation
3. Design of Shallow Foundation for Vertical Loads
4 P I
CONTENT OUTLINE
4. Pile Instalation
5. Design of Single Piles for Vertical Loads
6. Design of Pile Group for Vertical Loads
7. Design of Single Pile for Horizontal Loads
8. Special Cases (Shrink-Swell Soils, Downdrag andScour)
9 The Role of Load Testing9. The Role of Load Testing
10. Conclusion
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
4
5http://www.earth-engineers.com/DSC01903.JPG
SITE INVESTIGATION WHY IS BORING IMPORTANT?
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
MAYNE, P., CHRISTOPHER, B., & DEJONG, J. (2002).
SITE INVESTIGATION STANDARD PENETRATION TEST (SPT)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
5
6Advantages
1) Sampling Is Possible
MAYNE, P., CHRISTOPHER, B., & DEJONG, J. (2002)
SITE INVESTIGATION STANDARD PENETRATION TEST (SPT)
2) Simple
3) Suitable in many soil types
Disadvantages
1) Sample Disturbance
2) Not applicable for very soft or very loose soils
3) High Variability
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
MAYNE, P., CHRISTOPHER, B., & DEJONG, J. (2002)
SITE INVESTIGATION CONE PENETRATION TEST (CPT)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
6
7Advantages1) Fast and continuous
profile
Disadvantages1) Required skill
operator to run
MAYNE, P., CHRISTOPHER, B., & DEJONG, J. (2002)
SITE INVESTIGATION CONE PENETRATION TEST (CPT)
profile.
2) Applicable for soft soils.
3) Strong Theoretical basis in interpretation.
operator to run
2) No soil sample can be obtained.
3) Unsuitable for very hard or dense soils and large particles.
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
MAYNE, P., CHRISTOPHER, B., & DEJONG, J. (2002)
SITE INVESTIGATION SEISMIC PIEZOCONE TEST
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
7
8MAYNE, P., CHRISTOPHER, B., & DEJONG, J. (2002).
SITE INVESTIGATION PRESSUREMETER TEST (PMT)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
Advantages
1) Theoretically sound in determination of soil parameters
MAYNE, P., CHRISTOPHER, B., & DEJONG, J. (2002)
SITE INVESTIGATION PRESSUREMETER TEST (PMT)
soil parameters.
2) Applicable for larger zone of soil mass than any other in-situ test.
3) Develop complete stress vs strain curve
Disadvantages
1) It requires trained personel .
2) Time consuming (8 tests per day).
3) Delicate equipment.
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
8
91. Clays and Silts:
LABORATORY TESTS
Classification Tests, Undrained Shear Tests, Drained Shear Tests, Consolidation Tests
2. Sands and Gravels: Classification Tests
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
1. Load Resistance Factors Design (LRFD) Approach
2. Site Investigation
3. Design of Shallow Foundation for Vertical Loads
4 P I
CONTENT OUTLINE
4. Pile Instalation
5. Design of Single Piles for Vertical Loads
6. Design of Pile Group for Vertical Loads
7. Design of Single Pile for Horizontal Loads
8. Special Cases (Shrink-Swell Soils, Downdrag andScour)
9 The Role of Load Testing9. The Role of Load Testing
10. Conclusion
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
9
10
BEHAVIOR OF SANDS AND CLAYS UNDER LOAD CONDITIONS
DESIGN OF SHALLOW FOUNDATION
FSQu Qu Q (Load)
CLAYS
FSQu
SANDS
Q(Load)QuallSS >
FS QallSS p
'p=maximum past pressure experience by the soil
+ ovrc e '0
g1
++
+= pvv
cv
prc
oCCe
Hs '''
'
'
0
0 loglog1
0
--TIME RATE OF SETTLEMENT--SETTLEMENT OF SHALLOW FOUNDATION
v
drv
CHTt
2
= ( )maxH
HU tave
=
H1
H2
HZi
50% 90% Time, t
Hdr=Smallest Drainage Path
Uave= Average Degree of Consolidation
H3
H4
Settlement, H
Hmax
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
16
17
--ELASTIC SOLUTION--Q
SETTLEMENT OF SHALLOW FOUNDATION
( )21;
I q BS
E= BL
Qq =
B
E100 Su for clays E750 N(SPT) for clean sands E450 N(SPT) for silty sands
I=0.88 I=/45.0
88.0
=BLI
SHAPE FACTOR
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
B
PLAN VIEWB
B B
L D
--LOAD SETTLEMENT CURVE METHOD--SETTLEMENT OF SHALLOW FOUNDATION
PMT
P
2Ro
R
P P
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
R/Ro
PLLimit Pressure
17
18
0 . 2 4
O
s RB R
=
SETTLEMENT OF SHALLOW FOUNDATION
--LOAD SETTLEMENT CURVE METHOD--
pdeBLf PffffP .... ,/ = ( )Bef e /33.01 = Eccentricity
( ) 1.0, /18.0 BDf DB += Slope Proximity( )LBf BL /2.08.0/ += Shape
( ) 2190
/tan1
=
vh FFf Inclination
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
SETTLEMENT OF SHALLOW FOUNDATION
--LOAD SETTLEMENT CURVE METHOD--
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
18
19
SETTLEMENT OF SHALLOW FOUNDATION
--LOAD SETTLEMENT CURVE METHOD--
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
19
20
FIVE LARGE SPREAD FOOTINGS TESTS IN SANDS
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
LABORATORY TESTS
Water Content & Unit Weight
Atterberg Limits
IN-SITU TESTS
Borehole Shear Test & Cross-Hole
Wave Tests
FIVE LARGE SPREAD FOOTINGS TESTS IN SANDS
Atterberg Limits
Relative Density
Triaxial Test
Resonant Column Test
PiezoCone Penetration Test
Dilatomer Test
Pressuremeter Test
Step Blade Test
Standard Penetration Test & Cone
Penetration TestPenetration Test
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
20
21
FIVE LARGE SPREAD FOOTINGS TESTS IN SANDS
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
FIVE LARGE SPREAD FOOTINGS TESTS IN SANDS
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
21
22
FIVE LARGE SPREAD FOOTINGS TESTS IN SANDS
n
tt
SS
=
11
Creep Model
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
FIVE LARGE SPREAD FOOTINGS TESTS IN SANDS
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
22
23
FIVE LARGE SPREAD FOOTINGS TESTS IN SANDS
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
IMPORTANT FINDING
Pu (kPa) = 75 N
THE GENERAL BEARING CAPACITY DOES NOT WORK IN THIS CASE
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
DEVELOP ED THE LOAD SETTLEMENT CURVE METHOD
23
24
Comparison between Bearing Capacity Predictions and Measured Pressure at 150 mm of Se.
FIVE LARGE SPREAD FOOTINGS TESTS IN SANDS
Comparison between Predicted and Measured Load at 25 mm of Settlement
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
San Jacinto Monument Houston (1936)
LOADING:
Gross Pressure = 224 kPaMax Pressure (Dead + Wind) = 273 kPa
EXAMPLE - SAN JACINTO MONUMENT
Excavation= - 83 kPaNet Pressure=141 kPaNet Pressure after Mat Poured = 10 kPaPressure from Terraces = 34 kPa & 84 kPa
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
24
25
STRATIGRAPHY - SAN JACINTO MONUMENT
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
SOIL INDEX PROPERTIES
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
25
26
CONSOLIDATION CHARACTERISTICS
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
STRESS DISTRIBUTION
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
26
27
CONSOLIDATION CHARACTERISTICS
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
ACTUAL SETTLEMENT
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
27
28
ACTUAL SETTLEMENT
DESCRIPTION S(m)
CASE 8 (I l di R b d) 0 607CASE 8a (Including Rebound) 0.607
CASE 7a (Not including rebound) 0.370
DAWSONS PREDICTION 0.187
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
MEASURED SETTLEMENT 0.329
1. Load Resistance Factors Design (LRFD) Approach
2. Site Investigation
3. Design of Shallow Foundation for Vertical Loads
4 P I
CONTENT OUTLINE
4. Pile Instalation
5. Design of Single Piles for Vertical Loads
6. Design of Pile Group for Vertical Loads
7. Design of Single Pile for Horizontal Loads
8. Special Cases (Shrink-Swell Soils, Downdrag andScour)
9 The Role of Load Testing9. The Role of Load Testing
10. Conclusion
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
28
29
BORED PILES Concrete (dry drilling
or mud drilling), timberor steel piles.
Use in harder soils or
DRIVEN PILES Timber , Concrete, and
Steel.
Use in softer soils.
DESIGN OF DEEP FOUNDATION-TYPES OF PILES
Use in harder soils orfor high loads.
Nominal diametersranging from 0.40 to 4.0m.
Typical length rangingfrom 3 m to 45 m.
Nominal diametersranging from 0.30 to 3.0m.
Typical length rangingfrom 3.0 m to 60 m.
END BEARING PILES FRICTION PILES
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
WW
DRIVING ANALYSISN (bpf)
Set-Up
N (bpf)
W
I-II-
s
s
III-
End of Driving
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
29
30
http://www.vibropile.com.auhttp://www.coastalcaisson.com
DRILL DRY
INSTALATION OF BORED PILES
DRILL DRY
DRILL WET
USING CAISINGUSING CAISING
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
http://www.moretrench.com/~moretren/cmsAdmin/uploads/thumb2/Drilled_Shafts_001.jpg
DRILL DRY - BORED PILE INSTALLATION
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
30
31
http://www.kbtech.com/images/photos/Anderson%2022%20Cobble%20on%20Auger%20Pilot.jpg
DRILL WET - BORED PILE INSTALLATION
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
INSTALLATION OF BORED PILE WITH CAISING
http://www.agrafoundations.ca/images/large/3.0-Bored-Piles/Thumb-2.jpg
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
31
32
WAK
BULB, STRONG LAYER FIXED END
V
NON-DESTRUCTIVE TESTING FOR BORED PILES
time
cLt 2=
at A
FL
A
COMP. COMP.
time
cLt 2=
at A
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
NECKING, WEAK LAYER FREE END
VWAK
NON-DESTRUCTIVE TESTING FOR BORED PILES
F
time
cLt 2=
at A
L
A
COMP. TENS.
time
cLt 2=
at A
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
32
33
PILE DRIVINGhttp://images.google.com/imgres?imgurl=http://www2.dot.ca.gov/hq/esc/geotech/projects/t
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
h
W
PILE DRIVING ANALYSIS FOR DRIVEN PILES( )
3 0 0( ) 2
U De W h m mR c
N b p f
=+
L R
st
st
Load, Q
sb
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
Settlement, s
33
34
PILE DRIVING ANALYSIS FOR DRIVEN PILES
RUD
RUD
RUDTotal
EnergyElastic Energy
max( )
2.5UDeWh mmR =
Np(bpf)75e=efficiency of the hammerW= hammer weight
Scs
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
gh= drop heightNp= number of blow per footC= elastic compression (5mm?)RUD= ultimate resistance of the pileat the end of driving.
( )3 0 0( ) 2
U De W h m mR c
N b p f
=+
WAVE EQUATION ANALYSIS
2
2
2
2
tU
ER
AED
zU
=
Ec = Wave Velocity
WAK
RUD
=mass density of the pile
E=elastic modulus
A=cross sectional area of the pile
RUD= ultimate resistance of the pile at the end ofdriving
D
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
Np
L
34
35
WAVE EQUATION ANALYSIS
WAK WAK
D D
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
L L
+-
+
+
Soft Hard
Software: CAPWAP Driving ProcessPile CapacityPil I i
PILE DRIVING ANALYZER
h
W
Pile IntegrityStresses along the Pile
STRAINL R
Strain and
AccelerationTransducers
st
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
ACCELERATIONsb
time
35
36
1. Load Resistance Factors Design (LRFD) Approach
2. Site Investigation
3. Design of Shallow Foundation for Vertical Loads
4 P I
CONTENT OUTLINE
4. Pile Instalation
5. Design of Single Piles for Vertical Loads
6. Design of Pile Group for Vertical Loads
7. Design of Single Pile for Horizontal Loads
8. Special Cases (Shrink-Swell Soils, Downdrag andScour)
9 The Role of Load Testing9. The Role of Load Testing
10. Conclusion
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
pufuu QQQ +=ApAfQ +
QuQu
Working
ULTIMATE BEARING CAPACITY OF A SINGLE PILE
pusuu ApAfQ +=fu= Ultimate Skin Friction (kPa)
As= Surface Area
L fu QfuUltimate
Load
Working Load
pu= Ultimate Point Pressure (kPa)
Ap= Point Areapu Qpu
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
36
37
Short and Long TermULTIMATE POINT RESISTANCE FOR DRIVEN PILES
For Clays -Short Term.uSq 9max =For Clays Long TermN'
( ) ( ) 5.0max 1000 NkPaq = For Sands (Short & Long Term)
For Clays -Long Term (Nq from API)
For Sands -Short & Long Term
qvo Nq max =
qvo Nq'
max =
Others Methods are based on Pressuremeter and Cone Penetration Test
Frank, R. (1997), Calcul des Fondations Superficielles et Profondes, Presses de LEcole Nationale des Ponts et Chaussees, pp141
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
(Nq from API)
Short and Long TermULTIMATE FRICTION FOR DRIVEN PILES IN CLAY
uu Sf =max 'max vuf =
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
37
38
ULTIMATE FRICTION FOR DRIVEN PILES IN SAND
For Piles in Sand
Short and Long Term'
max vuf =
( ) ( ) 7.0max 5 NkPafu =N=SPT blow count
For Bored Piles Usefumax=0.75fumax (Driven)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
For Clays:KPaSSuf 275550 =
Reese & ONeilNc
S
Square
ULTIMATE BEARING CAPACITY OF A BORED PILE
KPaSSuf uu 27555.0 =
92.016;
+==
bcucu B
LNSNP
0.5' ; 1 .5 0.135( ( )) ;f z ft = =
D/B
Strip
For Sands:; 1 .5 0.135( ( )) ;
0.25 1.2; 200u v
u
f z ftf kPa
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
Pu(kPa)=57 NSPT for 0 NSPT75 blows per footPu= 4300 kPa for NSPT 75 blows per foot
38
39
FOR MORE INFORMATION ON DOWNDRAG VISIT:
PILNEG, free software
http://ceprofs.tamu.edu/briaud/
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
http://ceprofs.tamu.edu/briaud/
Briaud J.-L., Tucker L.M., 1998, Design guidelines for downdrag on uncoated and bitumen coated piles, NCHRP Report 393, National Academy of Sciences.
Qu
Qu
CRITICAL DEPTH OF A SINGLE PILE
Nc
St i
Square9.0
SKEMPTONS CHART
L1 fu
Dc=4B
LAYER 1
D/B
Strip7.0
4.0Jean Louis BRIAUD TEXAS A&M UNIVERSITY
pu
B
4B LAYER 2
39
40
Qtop
Stop
SETTLEMENT FOR SINGLE PILES
GENERAL APPROACH
L
Stop
fu
AELPSS avebottomtop +=
0 .6 (? )a v e to pP Q=
q SbottomJean Louis BRIAUD TEXAS A&M UNIVERSITY
( )EBpIs bottom
21 =
QtopQ
QwTf1
1111 21
sp AfAqP += AEPLww += 12
SETTLEMENT FOR SINGLE PILES
P3
Qtop
P2
L1 f1
L2
w3
wT
f2
w
f
f2
w
w q1
P1
q
L3
w1
w2f3 f1
w
q
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
40
41
1. Load Resistance Factors Design (LRFD) Approach
2. Site Investigation
3. Design of Shallow Foundation for Vertical Loads
4 P I
CONTENT OUTLINE
4. Pile Instalation
5. Design of Single Piles for Vertical Loads
6. Design of Pile Group for Vertical Loads
7. Design of Single Pile for Horizontal Loads
8. Special Cases (Shrink-Swell Soils, Downdrag andScour)
9 The Role of Load Testing9. The Role of Load Testing
10. Conclusion
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
QusingleQugroup
ULTIMATE LOAD CAPACITY OF A PILE GROUP
L L
Zone of Influence
gleuugroup enQQ sin=e=overall efficiency factor 1.0
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
41
42
BLOCK FAILUREANALYSIS OF A PILE GROUP FOR CLAYEY SOILS
Qugroup
L
D
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
( ) BLSNDLBSQ ucuublock ++= 2( )min ,ugroup usingle ublockQ nQ Q=
B L
LOAD TRANSFER FOR A PILE GROUP ANALYSIS
Qugroup Qugroup
2/3L L L
Hard Layer
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
Transfer the Load to 2/3 L if the Soil is uniform (Friction Piles)
Transfer the Load to the bottom if there is a hard layer
(End Bearing Pile)
42
43
CASE HYSTORY NEW ORLEANS HOSPITAL10000 Timber Piles0.3 m diameter (average)16 Story-Building15 m Long
1500 MN
15 m Long Soft Clay at the top2m thick dense sand at 14.5 m
Su=20 kPa
H
H=2 m
H=14.5 m
SandLOAD
Load Test for a Single Pile
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
Su=30 kPa
H1
H2
H3
H4
H=83.5 m
H5
L
Weight of the Hospital=1500 MNRu for one pile = 300 kN10000 x Ru=3000 MN ----FS=2.0 ok.
1500 MN
CASE HYSTORY NEW ORLEANS HOSPITAL
Hi v Uo b a H=xHi
Ultimate Block Capacity= 1200 MN (PROBLEM)
Htotal = 0.50 m
H
H=2 m
H=14.5 m
H1
H2
H3
H4
H=83.5,
H5
43
44
1. Load Resistance Factors Design (LRFD) Approach
2. Site Investigation
3. Design of Shallow Foundation for Vertical Loads
4 P I
CONTENT OUTLINE
4. Pile Instalation
5. Design of Single Piles for Vertical Loads
6. Design of Pile Group for Vertical Loads
7. Design of Single Pile for Horizontal Loads
8. Special Cases (Shrink-Swell Soil, Downdrag andScour)
9 The Role of Load Testing9. The Role of Load Testing
10. Conclusion
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
DESIGN OF SINGLE PILE FOR HORIZONTAL LOADS
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
44
45
DESIGN OF SINGLE PILE FOR HORIZONTAL LOADS
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
DESIGN OF SINGLE PILE FOR HORIZONTAL LOADS
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
45
46
DESIGN OF SINGLE PILE FOR HORIZONTAL LOADS
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
ULTIMATE HORIZONTAL LOAD
oov lLforlD 34>
=
DESIGN OF SINGLE PILE FOR HORIZONTAL LOADS
vlou BDpH 43=
ov lLforLD 3lo
Dv=L/3 for l
47
FIXED HEAD BEHAVIOR FREE HEAD BEHAVIOR
Houyo
M
Houyo
M
DESIGN OF SINGLE PILE FOR HORIZONTAL LOADS
Ly'o=0 L
0' oy
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
L =length pile
Hou =ultimate horizontal load
M =moment at the top of the pile
yo = horizontal displacement at the top of the pile
y'o =deflection at the top of the pile
HORIZONTAL DISPLACEMENT @Hou/3
DESIGN OF SINGLE PILE FOR HORIZONTAL LOADS
GENERAL CASE
oo lLfMH 322 L d Fl ibl
P li it f PMT
yo
oEK 3.2=
oo
o
o
oo lLforklKl
y 32 >+=( )
2
2 2 3o oo o
H L My for L l
KL += = L d Fl ibl
P li it f PMT
oo
o lLforKly 3>=
oo
o lLforLKHy 3lo
Dv = L/3 for l= L d Fl ibl
P li it f PMT
yo
oEK 3.2=
oo
o lLforKly 3>=
oo
o llforKLHy
49
DESIGN OF SINGLE PILE FOR HORIZONTAL LOADS
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
( )( )
n
ooou
ou
tt
tHtH
= ( )( )
n
ooo
o
tt
tyty
=
LONG TERM LATERAL LOAD
n=0.01 to 0.03 in sands
n=0.02 to 0.08 in clays
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
Hou= ultimate horizontal load at time t
Hou= ultimate horizontal load at time to
yo = lateral deflection at time t
yo = lateral deflection at time to
49
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( )( )
n
tt
tRtR
=
( )( )
= ot
tRtR
nlog
n VALUES FROM THE PRESSUREMETER TEST
n=0.01 to 0.03 in sandsn=0.02 to 0.08 in clays
( ) oo ttR
ottlog
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
R(t)= change in the radius of the cavity at time t
R(t0)= change in the radius of the cavity at time to
n VALUES FROM THE PRESSUREMETER TEST
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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aN Nyy 1=
a averages 0.1 for clays (one way and two way)
CYCLIC LATERAL LOADING
a averages 0.08 for sands under one way loading
a averages 0 for sands under two way loading
HoONE WAY CYCLIC
HoTWO WAY CYCLIC
y
LOADING
y
TWO WAY CYCLIC LOADING
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
aN NRR = R
R
a
Nlog1
a FROM THE PRESSUREMETER TEST
PMT ONLY APPLICABLE FOR ONE WAY
R 1 ( )Na log =
CYCLIC LOADING
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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THE PRESSUREMETER TEST
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
THE PRESSUREMETER TEST
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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LATERAL LOAD NEAR A TRENCH
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
trenchnotrench HH =LATERAL LOAD NEAR A TRENCH
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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FUTURE WORK IN RETAINING WALLS
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
EARTH PRESSURE COEFFICIENT VS MOVEMENT/HEIGHT
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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Hou Hou
FIXED HEAD BEHAVIOR
DESIGN OF PILE GROUP FOR HORIZONTAL LOADS
L L
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
( ) ( )gleougroupou enHH sin=n= number of piles
e=efficiency factor
Direction of the Load
4 DIAMETER PENETRATION AND 0.5- DIAMETER CLEAR SPACING
GROUP EFFICIENCY FOR HORIZONTALLY LOADED PILES
0.33 0.360.31
Fraction of the Load
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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0.20 0.18 0.14 0.20 0.28
8 DIAMETER PENETRATION AND 0.5 DIAMETER CLEAR SPACING
GROUP EFFICIENCY FOR HORIZONTALLY LOADED PILES
8 DIAMETER PENETRATION AND 1.0- DIAMETER CLEAR SPACING
0.21 0.17 0.17 0.18 0.26
8 DIAMETER PENETRATION AND 2.0- DIAMETER CLEAR SPACING
0.19 0.19 0.19 0.19 0.24
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
1. Load Resistance Factors Design (LRFD) Approach
2. Site Investigation
3. Design of Shallow Foundation for Vertical Loads
4 P I
CONTENT OUTLINE
4. Pile Instalation
5. Design of Single Piles for Vertical Loads
6. Design of Pile Group for Vertical Loads
7. Design of Single Pile for Horizontal Loads
8. Special Cases (Shrink-Swell Soils, Downdrag andScour)
9 The Role of Load Testing9. The Role of Load Testing
10. Conclusion
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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Soil Movement
FOUNDATION ON SHRINK-SWELL SOILS
h=active zoneShrink Swell Soil w
Water Content Profile
d
w
i
wi
i
i
i wE
wfHH
=== 33.0
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
Shrink-Swell SoilShrinking
Qu
SwellingQu
FOUNDATION ON SHRINK SWELL SOILS
L
h=active zoneLOAD
Qu
Qp
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
Shrinking
Swelling )( hLDfL uLOAD = DhfL uLOAD =
4)(
2DphLDfL uuLOAD +=
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STIFFENED SLAB ON PIERS
FOUNDATION ON SHRINK SWELL SOILS
ELEVATED STRUCTURAL SLAB ON PIERS
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
THIN POST TENSIONED SLAB ON GRADE
FOUNDATION ON SHRINK SWELL SOILS
STIFFENED SLAB ON GRADE
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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DOWNDRAG ON PILES
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
PILE POINT BEHAVIOR
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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2(1 )4
ppunch
s
Q Dv
AE =
PILE POINT BEHAVIOR
punch = Pile point movement
= Poissons ratio
Qp= Point resistance
A= Area of pile pointA= Area of pile point
D= Diameter of pile point
Es= Soil modulusFor clays = Es = 100 Su = EPMTFor sands=Es (kPa) = 750 N = 2 EPMT
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
EXAMPLE OF DOWNDRAG ON SINGLE PILES
Pile Ultimate Capacity
Qu = 706 + 1000
Q = 1706 kNQu 1706 kN
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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EXAMPLE OF DOWNDRAG ON SINGLE PILES
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
Qfn(group)Qfn(single)
DOWNDRAG FOR A GROUP OF UNCOATED PILES
LL
s s sCorner Piles
Side Piles
Internal Piles
( ) ( )glefngroupfn QQ sin5.0=
( ) ( )glefnsidefn QQ sin40.0=
( ) ( )glefnernalfn QQ sinint 15.0=
5.2=dsfor
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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SCOUR TYPES
Probable Flood Levelys(Abut) Applies ys(Cont) Applies
CL
Normal Water Level
ys(Abut)
y s(pier) y s(Cont)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
is Abutment Scour Depthis Contraction Scour Depthis Pier Scour Depth
Where, ys(Abut)y s(Cont)y s(pier)
( )0.7( ) 1 ( ) ( )2.2 2.6's Pier w L sp pier c piery K K K K Fr Fra = 0.33
1 10.89 , for 1.43' 'w
y yK a a
=
1.0, for whole range of /LK L a=0.91
2.9 , for 3.42' '
1 0 elsesp
S SK a a
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OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
Case 1 - Big Scour Hole
26% Observed Occurrence
Case 2 Settlement of Pier
32% Observed Occurrence
Case 3 - Loss of Deck
5% Observed Occurrence
Case 4 - Loss of Pier
37% Observed Occurrence Jean Louis BRIAUD TEXAS A&M UNIVERSITY
OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
126
Case 1 - Big Scour Hole
26% Observed Occurrence
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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Courtesy of the University of Kentucky at Louisville
OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
129
Case 2 Settlement of Pier
32% Observed Occurrence
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
134
Case 3 - Loss of Deck
5% Observed Occurrence
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
Hatchie River Bridge, Tennessee
OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
138
Case 4 - Loss of Pier
37% Observed Occurrence
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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OBSERVED FAILURE MODES OF BRIDGE DUE TO SCOUR(based on failure photos in Briauds files)
This distance should be made larger to decrease
the risk of collapse
145Jean Louis BRIAUD TEXAS A&M UNIVERSITY
STRUCTURAL
and
GEOTECHNICAL
THE ROLE OF SOIL STRUCTURE-INTERACTION
Qu Q
S
k1
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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1. Load Resistance Factors Design (LRFD) Approach
2. Site Investigation
3. Design of Shallow Foundation for Vertical Loads
4 P I
CONTENT OUTLINE
4. Pile Instalation
5. Design of Single Piles for Vertical Loads
6. Design of Pile Group for Vertical Loads
7. Design of Single Pile for Horizontal Loads
8. Special Cases (Shrink-Swell Soils and Downdrag)
9. Example Problems
0 T T10.The Role of Load Testing
11. Conclusion
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
Laboratory testing brings the problem of sampledisturbance . However, its application is valuable for theunderstanding of some properties that can not bedetermined using In-Situ Tests.
THE ROLE OF LABORATORY TESTING
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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THE ROLE OF IN-SITU TESTINGMAYNE, P., CHRISTOPHER, B., & DEJONG, J. (2002).
In-situ testing gives a good estimation of the soil properties byreducing the problem of sample disturbance.
Its application depends on the project magnitude and importance.
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
http://images.google.com/imgres?imgurl=http://
THE ROLE OF LOAD TESTING: SONIC INTEGRITY TEST
SONIC-INTEGRITY: is an in-situ test that helps to locatepotential problems in bored piles.
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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Hydraulic
Jack and Gauges
Q(Load)Qu Qu
LOAD
RXRX
THE ROLE OF LOAD TESTING: STATIC LOAD TEST FOR PILES
Q(Load)
0.1B
QuQuAEL
L
RX
SANDS
S(Settlement) CLAYS
AEQLBS e += 1.0
L
Reaction Piles
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
http://www.earth-engineers.com/Pile%20Load%20Test%20%281%29.jpg
THE ROLE OF LOAD TESTING: STATIC LOAD TEST FOR PILES
It provides the load curve of an installed pile. From that,the ultimate load resistance of the pile can be determined.
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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STATIC LOAD TEST FOR SHALLOW FOUNDATION(Texas A&M University Load Tests)
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
THE ROLE LOAD TESTING: STATNAMIC TEST www.statnamiceurope.com/
The Statnamic is another load test that provides a loadSettlement curve of an installed pile.
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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STATNAMIC LOAD TEST FOR SINGLE PILES
Q(Top Load)BANG
Q( p )ChargeBIG MASS
LASER
Calibrated
Dynamic
stop
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
S(Top Settlement)
Ly
Load Cell
Sbottom
OCELL INSTALLATIONFROM: HTTP://WWW.LOADTEST.COMTransducers
HC
THE ROLE OF LOAD TESTING: OSTERBER CELL TEST
L
Load Cell
Hydraulic Control
Steel Plates
Tested Area
Load Cell
Reaction Area
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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1. Load Resistance Factors Design (LRFD) Approach
2. Site Investigation
3. Design of Shallow Foundation for Vertical Loads
4 P I
CONTENT OUTLINE
4. Pile Instalation
5. Design of Single Piles for Vertical Loads
6. Design of Pile Group for Vertical Loads
7. Design of Single Pile for Horizontal Loads
8. Special Cases (Shrink-Swell Soils and Downdrag)
9. Example Problems
0 T T10.The Role of Load Testing
11. Conclusion
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
Foundation engineering requires:
1. A good understanding of site conditions including Geology
CONCLUSION
2. Proper use of theory in design
3. Safety against ultimate capacity
4. Allowable movements
5. Good experience and engineering judgementjudgement
6. Appropriate specifications
7. Quality control during construction
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
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MORE REFERENCES
BRIAUD, J.L., SALLOP: Simple Approach for Lateral Loadson Piles, Journal of Geotechnical and GeoenvironmentalEngineering, Vol. 123, No. 10, pp. 958-964, ASCE, NewYork, October 1997.
BRIAUD, J.L., The Pressuremeter, A. A. Balkema, Rotterdam,Netherlands, 1992.
ASSHTO LRFD (Load Resistance Factor Design).
BRIAUD J L GIBBENS R B h i f Fi S d
Jean Louis BRIAUD TEXAS A&M UNIVERSITY
BRIAUD J.-L., GIBBENS R., Behavior of Five SpreadFootings in Sand, Journal of Geotechnical andGeoenvironmental Engineering, Vol. 125, No.9, pp. 787-797,September 1999, ASCE, Reston, Virginia.
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