Details regarding the thermal integrity profiling of pile foundations

1. Thermal Integrity Profiling
of Concrete Deep Foundations
Drilled Shaft Design & Construction Seminar
Gray Mullins, Ph.D., P.E.
Professor, University of South Florida

2. Outline
 Background
 What do TIP results show?
 Case Studies
 Testing Equipment and Procedure
 Analysis
 Field Demonstration???

3. Visual Inspection (sometimes?)

4. I – 4, Orlando, FL
Crosstown Expressway, Tampa, FL
Visual Inspection (but limited)

6. I - 4 & SR 400

7. I - 4 & SR 400

11. 0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
3.3 4.3 5.3 6.3 7.3 8.3 9.3
Shaft Diam. (ft)
Testing
Coverage
1 1.5 2 2.5 3
Shaft Diam. (m)
GGL Shaft Tested GGL Cover Tested CSL Shaft Tested CSL Cover Tested
GGL
CSL

12. Principles of Thermal Integrity Profiling

13. What do TIP results show?
 Tests the entire volume of concrete
 Cage alignment
 Estimated shaft shape
 Necks, bulges, or inclusions
 Concrete cover
 Quality of concrete

18. Hydration Energy

19. 1
4
7
10
13
16
19
22
25
28
31
34
37
40
43
46
49
S1
S10
S19
S28
S37
S46
20
30
40
50
60
70
80
70-80
60-70
50-60
40-50
30-40
20-30
Single Shaft Heat Signature
Elevated Soil
Temperature
Higher
Temperature

20. How Much Energy is in a Drilled Shaft?

21. Effect of Cement Content on Temperature
75
100
125
150
175
200
225
250
0 10 20 30 40 50 60 70 80 90 100
Hydration Time (hrs)
Core
Temperature
(F)
860PCY
600PCY
430PCY
6 ft shaft

22. Effect of Mix Design on Temperature
4 ft shaft

23. Effect of Shaft Diameter on Temperature
(How long can tests be performed?)

24. Field Testing and Equipment
 Method A (probe method)
 Lower a thermal probe down dry access tubes
 Monitor depth of probe with encoder wheel
 Run one test near peak temperature
 Method B (thermal wire method)
 Install thermal wires beside or in lieu of access tubes
 Attach a data collector to each thermal wire
 Data is collected at user prescribed intervals (e.g. 15
min)

25. Thermal Probe
Data Acquisition System
Infrared Sensors
Equipment (Method A)
Depth Encoder Assembly

26. Field Testing (Method A)


27. Equipment (Method B)

28. What should I see in the thermal profiles?

29. Cage
Diameter
Excavation
Diameter
60 80 100 120 140 160 180
Depth
(ft)
Temperature (F)
Convection
to air
Conduction
to soil

30. Cage
Diameter
Excavation
Diameter
Convection
to air
Conduction
to soil

31. Cage
Diameter
Excavation
Diameter
60 80 100 120 140 160 180
Depth
(ft)
Temperature (F)
60 80 100 120 140 160 180
Depth
(ft)
Temperature (F)
Convection
to air
Conduction
to soil

33. Effects of Alignment and Shaft Radius
Radial Position (ft)
Temperature (F)

34. Field Observations
 Little to no cage
eccentricity (all tubes
same temp throughout)
 Probable location of
water table at 17-18 ft
(causes sloughing until
slurry is fully in place)
 Clean top and toe
signature (approximate
1 diameter temperature
roll-off top and bottom)
 Good Shaft
0
5
10
15
20
25
30
35
40
70 80 90 100 110 120
Temperature (deg F)
Depth
(ft)
T1
T2
T3
T4
Avg
Scatter Creek
Shaft A

35. 0
5
10
15
20
25
30
35
60 70 80 90 100 110 120 130
Temperature (deg F)
Depth
(ft)
-25.5
-20.5
-15.5
-10.5
-5.5
-0.5
4.5
9.5
Elevation
(ft)
Avg
T1
T2
T3
T4
TOS
BOS
BOC
Bridge 100443
Pier 20-4 Shaft 2
0
5
10
15
20
25
30
35
60 70 80 90 100 110 120 130
Temperature (deg F)
Depth
(ft)
-25.8
-20.8
-15.8
-10.8
-5.8
-0.8
4.2
9.2
Elevation
(ft)
Avg
T1
T2
T3
T4
TOS
BOS
BOC

36. How does TIP estimate shaft shape,
radius, and cover?

37. Concrete Yield
Plots
 Depth change
per truck
 Volume per
truck
 Convert to avg
diam or radius
per truck

38. 0
10
20
30
40
50
60
70
80
90
100
Depth
(ft)
0
5
10
15
20
25
30
0 2 4 6 8 10
Shaft Diameter
Depth
(m)
Grnd Surf
TOS
WT
BOC
Loose Sand
TOR
BOS
Effective
Diam.
Theoretical
Diam.
No Correction for
Over-pouring Concrete
No Correction for
Tremie filling / volume
0 3 (m)
1 2
(ft)
0
10
20
30
40
50
60
70
80
90
100
80 100 120 140
Temperature
Depth
(ft)
0
5
10
15
20
25
30
0 2 4 6 8 10
Shaft Diameter
Depth
(m)
Average
Grnd Surf
TOS
WT
BOC
Loose Sand
TOR
BOS
Effective
Diam.
Theoretical
Diam.
No Correction for
Over-pouring Concrete
No Correction for
Tremie filling / volume
0 3 (m)
1 2
(ft)
30 60 (ºC)
40 50
(ºF)

39. Temperature to Radius Conversion
R = 0.8113T - 51.265
0
10
20
30
40
50
60
114 116 118 120 122 124 126 128
Temperature (F)
Radius
(in)

40. 0
10
20
30
40
50
60
70
80
90
100
20 30 40 50 60 70
Radius (in)
Depth
(ft)
t1
t2
t3
t4
t5
t6
t7
avg
TOS
WT
BOC
TOLime
TOR
BOS
Effective Radius
Convert Temp
to Radius
 Good agreement
with yield plot
information
 Check tube /
cage cover

41. 0
20
40
60
80
100
20 30 40 50 60 70
Effective Radius (in)
Depth
(ft)
t1
t2
t3
t4
t5
t6
t7
avg
TOS
WT
BOC
TOLime
TOR
BOS
Effective Radius
Individual
Tube Positions
 Check tube /
cage cover
 Three tubes
touch side walls
others with
reduced cover
Design Radius of Shaft
Outer Radius of Cage

43. Effects of Alignment, Radius and Time
Radial Position (ft)
Temperature (F)

53. Y
axis
X axis
(independent)

62. How do I distinguish between normal end
effects and an anomaly?

64. 90
95
100
105
110
70 80 90 100 110 120 130 140
avg
toe
tanh
corrected

65. avg
toe
tanh

66. 90
95
100
105
110
70 80 90 100 110 120 130 140

67. 80
85
90
95
100
105
110
70 80 90 100 110 120 130 140
Depth
(ft)
Temperature (F)
Toe Correction
avg
toe
tanh
80
85
90
95
100
105
110
70 80 90 100 110 120 130 140
Depth
(ft)
Temperature (F)
Toe Correction
avg
toe
tanh
corrected

68. Comparison: FGE

69. 0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
90 100 110 120 130 140 150
Depth
(ft) Temperature (F)
Average
T-1
T-2
T-3
T-4
TOS
BOC
Permanent Casing
(straight shaft)
O-Cell (less concrete)
T-1
T-3
T-4 T-2
Bulge (more concrete)

70. 0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
90 100 110 120 130 140 150
Depth
(ft) Temperature (F)
Average
T-1
T-3
TOS
BOC
T-1
T-3

71. 0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
90 100 110 120 130 140 150
Depth
(ft) Temperature (F)
Average
T-2
T-4
TOS
BOC
T-4 T-2

72. -1 0 1 2 3 4 5 6 7 8 9 10
-114.4
-109.4
-104.4
-99.4
-94.4
-89.4
-84.4
-79.4
-74.4
-69.4
-64.4
-59.4
-54.4
-49.4
-44.4
-39.4
-34.4
-29.4
-24.4
-19.4
-14.4
-9.4
-4.4
0.6
5.6
10.6
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
125
17 18 19 20 21 22 23 24 25 26 27 28
Effective Concrete Cover (in)
Elevation
(ft)
Depth
(ft)
Effective Shaft Radius (in)
AVG
T1
T2
T3
T4
TOS
BOS
OcellT
OcellB
BPC
GSE
Cage
-5
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
125
130
-40 -30 -20 -10 0 10 20 30 40
Depth
(ft)
Shaft Radius (in)

73. -114.4
-109.4
-104.4
-99.4
-94.4
-89.4
-84.4
-79.4
-74.4
-69.4
-64.4
-59.4
-54.4
-49.4
-44.4
-39.4
-34.4
-29.4
-24.4
-19.4
-14.4
-9.4
-4.4
0.6
5.6
10.6
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
125
0 0.5 1 1.5 2 2.5 3
Elevation
(ft)
Depth
(ft)
Cage Offset (in)
-114.4
-109.4
-104.4
-99.4
-94.4
-89.4
-84.4
-79.4
-74.4
-69.4
-64.4
-59.4
-54.4
-49.4
-44.4
-39.4
-34.4
-29.4
-24.4
-19.4
-14.4
-9.4
-4.4
0.6
5.6
10.6
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
125
0 45 90 135 180 225 270 315 360
Elevation
(ft)
Depth
(ft)
Cage Offset Direction
TOS
BOS
W SW S SE E NE N NW W

74. What is the TIP zone of detection?
 The zone is limited only to the size of anomaly
that can be detected.
 Large anomalies are detected by multiple tubes (or
wires)
 Smaller anomalies are only detected by the closest
tube or wire
 A 10% cross sectional inclusion is detected by
multiple tubes (or wires)

75. 0
5
10
15
20
25
110 120 130 140 150 160
Temperature (F)
Depth
(ft)
0
1
2
3
4
5
6
7
43 48 53 58 63 68 73
Temperature (C)
Depth
(m)
Tube 1
Tube 3
Tube 5
Avg
1
3
5
1
3
5
Cross-Section A
Top Anomaly
Cross-Section B
Bottom Anomaly
Steel Logging Tubes
PVC Logging
Known Anomaly

76. Summary
TIP measurements:
 Tests the entire volume of concrete
 Identify cage alignment
 Estimated shaft shape
 Show necks, bulges, or inclusions
 Determine concrete cover
 Quality of concrete

77. Questions?

78. Portland
Cement Water
Hardened
Cement
Heat
Cement hydration is a highly exothermic process!