A Study of Anchored Fiber
Reinforced Plastics Sheet Pile
1
Yeou-Fong Li and Ching-Kai Chen2
1
Professor of the Department of Civil Engineering , NTUT, Taipei, Taiwan .
2
Master of the Department of Civil Engineering, NTUT, Taipei, Taiwan.
Introduction: FRP (Fiber Reinforced Plastics) composite materials have the merits of light weight, high strength, welldurability and other characteristics. In this study, FRP sheet piles were used to solve the corrosion problem of the
geotechnical structures.
Keywords： Glass Fiber Reinforced Plastic Composite Material, Frame, Grating, Pushover Test
Angle
45°
60°
90°
Stiffness (kN/mm)
0.957
1.104
1.115
Cross section area(cm2)
93.86
95.94
105.868
0.01020
0.011507
0.01053
3 Points Bending moment Experiment
First, the 3-point bending experiment was performed, and changing
the span depth ration to obtain the specimen’s stiffness. The specimen
of 18-span depth ratio whose displacement is more approach to
Euler’s Beam theory from the experimental observation.
Span depth ratio
18
14
10
8
Experience(mm)
18.12
9.59
4.86
2.84
Euler’s beam(mm)
18.54
8.66
3.16
1.64
Error
Timoshenko’s
beam(mm)
Error
2.32%
9.70%
34.98%
42.25%
21.59
11.03
4.66
2.99
Stiffness/Cross section
area (kN/mm·cm2)
Moment of inertia(cm4)
6,496
7,082
8,954
Stiffness/Moment of
inertia (kN/mm·cm4)
0.000161
0.000156
0.000125
版樁厚度
6.35
12.70
19.05
Stiffness(kN/mm)
1.10
2.24
3.17
0.011507
0.013272
0.013953
0.000186
0.000192
0.000196
Stiffness/Cross section
area (kN/mm·cm2)
Stiffness/Moment of
inertia (kN/mm·cm4)
Plaxis Analysis Result
Then, three kinds of sheet piles (FRP, PVC and steel) were modeled
19.15%
15.02%
4.12%
5.28%
using Plaxis. We found that the PVC sheet pile has the lowest stiffness
which causes its deflection concerns and a very low safety factor. On
Ansys Analysis Result
the other hand, the steel sheet pile enjoys the highest stiffness, lowest
Using the result of the experiment to feedback the finite element deflection and consequently, the largest safety factor. Furthermore, in
analysis model, and then we found the error of numerical model’s order to improve the safety of the slope of the embankment, this study
result is less about 8.5 %.
compares results of the the cantilever with the anchored FRP sheet
pile. According to the results, the safety factor of the anchored FRP
跨深比
18
14
10
8
sheet pile is higher than cantilever one by 1.9 folds.
跨度(m)
3.66
2.84
2.03
1.63
ANSYS(mm)
實驗值(mm)
18.28
18.12
9.49
9.59
4.45
4.86
2.70
2.84
ANSYS與實驗相對誤差
0.16%
0.10%
8.44%
4.93%
18-span depth ratio
14-span depth ratio
版樁材料
FRP版樁
PVC版樁
鋼板樁
極限強度
460.38 MPa
54.92 MPa
390.00 MPa
打樁深度
10-span depth ratio
8-span depth ratio
最大
安全
最大
安全
最大
安全
彎矩
係數
彎矩
係數
彎矩
係數
4.72MP
4.70
5.44MP
1m
Then changing the numerical model’s angle and thickness to
investigate the stiffness and stiffness over cross section area.
According to the numerical FRP sheet pile model, the 60°-angle FRP
sheet pile is most economical between 45°, 60° and 90°. Furthermore,
the thickness of the 19.05 mm FRP sheet pile is more economical than
the thickness of the 6.35 mm and 12.70 mm FRP sheet piles.
a
97.6
MPa
11.7
a
71.7
2m
5.97
77.2
3.16
17.4
9.22
42.3
3m
5.77
79.8
4.26
12.9
11.08
352
打設深度
懸臂式安全係數
錨碇式安全係數
提升之安全係數
1m
1.74
4.56
2.82
2m
2.56
4.82
2.26
3m
3.10
5.07
1.97
A Study of Anchored Fiber
Reinforced Plastics Sheet Pile
1
Yeou-Fong Li and Ching-Kai Chen2
1
Professor of the Department of Civil Engineering , NTUT, Taipei, Taiwan .
2
Master of the Department of Civil Engineering, NTUT, Taipei, Taiwan.
Introduction: FRP (Fiber Reinforced Plastics) composite materials have the merits of light weight, high strength, welldurability and other characteristics. In this study, FRP sheet piles were used to solve the corrosion problem of the
geotechnical structures.
Keywords： Glass Fiber Reinforced Plastic Composite Material, Frame, Grating, Pushover Test
Angle
45°
60°
90°
Stiffness (kN/mm)
0.957
1.104
1.115
Cross section area(cm2)
93.86
95.94
105.868
0.01020
0.011507
0.01053
3 Points Bending moment Experiment
First, the 3-point bending experiment was performed, and changing
the span depth ration to obtain the specimen’s stiffness. The specimen
of 18-span depth ratio whose displacement is more approach to
Euler’s Beam theory from the experimental observation.
Span depth ratio
18
14
10
6,496
7,082
8,954
Stiffness/Moment of
inertia (kN/mm·cm4)
0.000161
0.000156
0.000125
版樁厚度
6.35
12.70
19.05
8
Stiffness(kN/mm)
1.10
2.24
3.17
Stiffness/Cross section
area (kN/mm·cm2)
Stiffness/Moment of
inertia (kN/mm·cm4)
0.011507
0.013272
0.013953
0.000186
0.000192
0.000196
Experience(mm)
18.12
9.59
4.86
2.84
Euler’s beam(mm)
18.54
8.66
3.16
1.64
Error
Timoshenko’s
beam(mm)
Error
2.32%
9.70%
34.98%
42.25%
21.59
11.03
4.66
2.99
19.15%
15.02%
4.12%
5.28%
Ansys Analysis Result
Using the result of the experiment
analysis model, and then we found
result is less about 8.5 %.
跨深比
18
跨度(m)
3.66
ANSYS(mm)
實驗值(mm)
18.28
18.12
ANSYS與實驗相對誤差
0.16%
18-span depth ratio
Stiffness/Cross section
area (kN/mm·cm2)
Moment of inertia(cm4)
Plaxis Analysis Result
Then, three kinds of sheet piles (FRP, PVC and steel) were modeled
using Plaxis. We found that the PVC sheet pile has the lowest stiffness
which causes its deflection concerns and a very low safety factor. On
to feedback the finite element the other hand, the steel sheet pile enjoys the highest stiffness, lowest
the error of numerical model’s deflection and consequently, the largest safety factor. Furthermore, in
order to improve the safety of the slope of the embankment, this study
compares results of the the cantilever with the anchored FRP sheet
14
10
8
pile. According to the results, the safety factor of the anchored FRP
2.84
2.03
1.63
sheet pile is higher than cantilever one by 1.9 folds.
9.49
4.45
2.70
Material
9.59
4.86
2.84
FRP
PVC
Steel
Depth
0.10%
8.44%
4.93%
1m
1.71
1.54
1.71
14-span depth ratio
2m
3m
FRP Cantilever
sheet pile
10-span depth ratio
2.07
2.56
1.75
2.60
1.83
3.69
FRP Anchored
sheet pile
8-span depth ratio
Then changing the numerical model’s angle and thickness to
investigate the stiffness and stiffness over cross section area.
According to the numerical FRP sheet pile model, the 60°-angle FRP
sheet pile is most economical between 45°, 60° and 90°. Furthermore,
the thickness of the 19.05 mm FRP sheet pile is more economical than
the thickness of the 6.35 mm and 12.70 mm FRP sheet piles.
Depth
Safty Factor of Cantilever Sheet pile
Safty Factor of Anchored sheet pile
Increment of Safety Factor
1m
2m
3m
1.74
2.56
3.10
4.56
4.82
5.07
2.82
2.26
1.97