Dynamic and static horizontal load tests on steel pipe piles and theiranalyses
P. Kitiyodom & T. Matsumoto

Kanazawa University, Kanazawa, JapanK. Tomisawa

Civil Engineering Research Institute for Cold Region, Japan

E. Kojima & H. Kumagai

Japan Pile Corporation, JapanABSTRACT: In this research, dynamic and static load tests were performed on permanent foundation piles
for an abutment of a highway bridge, which had a pile length of 38 m, 800 mm in outer diameter and 9 or 12mm in wall thickness. The static horizontal load versus horizontal displacement derived from the dynamic
load test conformed well to that measured in the conventional static horizontal load test, encouraging the useof dynamic horizontal load testing as an alternative for the conventional static horizontal load testing.

For axial compressive pile load test methods, thedynamic load testing or the rapid load testing is
widely used in Japan because of the fact that thesemethods are unsusceptible to reaction piles, and require less time and cost compared with the conventional static load test where reaction piles are employed. Application of the dynamic or rapid pileload test to horizontal pile load test would be very
useful in seismic design of the pile foundation.
In Kitiyodom et al. (2006), the possibility of theuse of dynamic horizontal pile load test as an alternative method for the conventional static horizontal
load testing is presented and discussed. In order toestimate the deformation and load distribution of asingle pile subjected to dynamic horizontal load aswell as vertical load, a numerical program KWaveHybrid, has been proposed.
In this paper, the results of static and dynamic
horizontal load tests on the actual piles are presentedand compared. Static load displacement relation of
the pile is estimated using the soil parameters obtained from the wave matching analysis of dynamic
horizontal pile load test signals. Both static and dynamic analyses are performed using KWaveHybrid.
It is shown that the estimated results match very wellwith the measured values.

constructed piles, a static alternating cyclic horizontal load test and a dynamic horizontal load test werecarried out on the constructed foundation piles. The
test piles are located next to each other with pile
spacing of 2 m. The specifications of the test piles
are summarised in Table 1.
Figure 1 shows the profiles of soil layers and SPT
N-values at Shinotsu site. The soil profile at this site
is characterised by thick deposits of silt soils. SPT
N-values are typically less than 7, except for gravel
at depth from 35 m. At this site, soil improvement
was carried out prior to the pile load tests. The SPT
N-values after soil improvement are also shown inFigure 1.
SPT N-value
05

Organic silt

00102030405Fine sand

10Silt152015
Silty sand252025Silt

2 TEST DESCRIPTION

30

A bridge was constructed at the Shinotsu site for theCentral Hokkaido Connection Road in 2006. Pile
group foundations were employed for abutments ofthe bridge. In order to assess the performance of the35227

Peat10Depth from G.L. (m)1 INTRODUCTION

3035
After soil improvement
Before soil improvement

Gravel

4040

Figure 1. Profiles of soil layers and SPT N-values.

50

800
600
400
200
0-200-400-600-800

01236Total disp.
ElasticResidual

600
4002000-200-400-600-800-40-2002040

Horizontal displacement (mm)Figure 3. Static horizontal load vs horizontal displacement.

Direction1050
800
Displacementtransducer

Unit : mmFigure. 4. Loading and measuring devices for dynamic horizontal load test.

228

5800

Load cellAccelerometer
Accelerometer & Strain gauges

4

Elapsed time (h)Figure 2. Loading history in static horizontal load test.

Horisontal load (kN)

Alternating cyclic horizontal loads shown in Figure 2 were applied to the pile in the static load test.
Figure 3 shows the relationships between the horizontal load H and the horizontal displacement u. Theresidual displacement was measured at full recoveryof horizontal load to 0 in each load step, and theelastic displacement was obtained by subtracting theresidual displacement from the total displacement
measured at the maximum load in each loading step.
The residual displacement and the corresponding
elastic displacement at the maximum load in eachload step are also shown in Figure 3.
In the dynamic horizontal load test, the pile was
hit horizontally by a hammer of mass of 2.14 ton
through a coil spring which was attached to the loadcell at the point z = 0.3 m below the pile head asshown in Figure 4. Applied force, horizontal displacements and accelerations were measured at thesame level of the hit point with a sampling interval
and measuring devices areof 15 s. The loading
227 227
shown in Figure 4. More details can be found in Kojima et al. (2006).

Horizontal load (kN)

An example of the dynamic test signals is shownin Figure 5. The measured force increases and decreases smoothly with time, and has a peak of about
330 kN. The loading duration is about 55 ms. The
measured displacement also increases and decreases
with time having a peak of 20 mm at a time of 40
ms. The peak horizontal displacement delays 18 ms
behind the peak horizontal load, showing dynamiceffects.

Table
1. Specifications of the test piles.
____________________________________________
Property
Value____________________________________________
Length (m)38.0Embedment length (m)37.2Outer diameter (mm)800
Inner diameter (mm)upper part (z < 7.5 m)
12lower part (z > 7.5 m)
9Young s modulus (kPa)
2.06×108
Moment of inertia (cm4)upper part (z < 7.5 m)
2.31×105
lower part (z > 7.5 m)
1.75×105
Shear wave velocity (m/s)
3187
7.8
Density (ton/m3)
Mass(ton)
7.06____________________________________________

7

Horizontal load (kN)

350
300
250
200
150
100
500

During the dynamic horizontal load test, the axial
strains at both sides of the pile were measured at different levels down the pile shaft. Figure 6 shows theprofiles of bending moments along the pile obtained
from the measured axial strains.
Figure 7 shows the relationship between the dynamic horizontal load and the horizontal displacement. It can be seen from comparison between Figure 3 and Figure 7 that the measured load
displacement relation from the dynamic load test is
totally different from the measured static load displacement relation. Therefore, in order to obtain thestatic load displacement relation of the pile from themeasured signals of the dynamic load test, wave
matching analysis of the measured signals is needed.

Measured

0102030405060708090

Horizontal disp. (mm)Time (ms)(a) Horizontal load
25Measured
Calculated

20151050350
0102030405060708090300

Horizontal load (kN)Time (ms)(b) Horizontal displacement
Velocity (m/s)

1.0
Measured
Calculated

0.5
0.0
-0.5

01020304050607080

2Acceleration (m/s )150100Measured
Calculated

500510152025

Horizontal displacement (mm)Figure 7. Measured and calculated load vs displacement in dynamic horizontal load test.

MeasuredCalculated

3 ANALYSES OF TEST RESULTS

01020304050607080

A computer program KWaveHybrid, developed byKitiyodom et al. (2006), was used for the wave
matching analysis of the dynamic horizontal loadtest. The program was also used to estimate thestatic load displacement relationship of the pile using the soil parameters obtained from wave matching analysis.
Figure 8 illustrates the hybrid modelling of thepile and the soil used in KWaveHybrid. The pile ismodelled as beam elements with masses and the soilis treated as springs and dashpots. More details ofthe analysis method can be found in Kitiyodom et al.
(2006).
It should be noted here that the unloading and reloading curves measured in the static alternating cyclic load test (Figure 3) indicate that gapping between the pile and the surround soil occurs during
unloading and reloading stages. Such gapping has
not been incorporated in KWaveHybrid at present.
Hence, monotonic horizontal loading of the pile isconsidered in the analysis. Note also that the interiorof the pipe pile was almost filled with soil at the end90

Time (ms)(d) Horizontal accelerationFigure 5. Measured and calculated pile load test signals.
0Distance from pile head (m)200090Time (ms)(c) Horizontal velocity
500
400
300
200
1000-100-20025051015Measured
t = 10 ms
t = 30 ms
t = 50 ms

20
25Calculated
t = 10 ms
t = 30 ms
t = 50 ms

30
35
0

200

400

600

Bending moment (kN m)
Figure 6. Measured and calculated bending moment.

229

4 CONCLUSIONS

kh0
m0
c0

k0

ch0(Kp)1

kh1

m1
c1

k1

ch1(Kp)2

kh2

m2
c2 (Kp)3

k2(Kp) nch2khn

mn

cn

kn

chn
cb

kb

cb
mb

Figure 8. Hybrid modelling of the pile and the soil.
Table
2. Soil parameters identified in final matching.
___________________________________________
Depth (m)Gs (kPa)qh (kPa)___________________________________________
0 to 2.79615
116.0
2.7 to 18.4
836
Elastic range
18.4 to 31.8
1607
Elastic range
31.8
to37.011587
Elasticrange___________________________________________

Horisontal load (kN)of driving. It was assumed that the pipe pile was fulfilled by the soil with the density of 1.8 ton/m3, andthe masses of the soil inside the pipe pile was taken
into account in the analysis.
Matching analysis was repeated with assumed
values for the maximum shaft horizontal pressure,qh, and the soil shear modulus, Gs, using the measured dynamic load (Figure 5(a)) as the force boundary condition at the loading point, until a good
matching between the calculated and the measured
pile displacements was obtained. Soil parameters
used in the final matching of the pile are listed inTable 2.
Figure 5 and Figure 7 show the displacement, velocity, and acceleration versus time and load versus
displacement of the test pile calculated in the final
matching analysis, compared with the measured values. It can be seen that the calculated dynamic pile
displacement overestimated the measured values after the peak displacement. This is thought to be dueto the soil spring in KWaveHybrid. At the present,the values of the soil spring in KWaveHybrid during
the loading and unloading states are the same. The
values of the soil spring during the loading andunloading states should be different due to gapping
between the pile and the surrounding soil as mentioned earlier. However, the calculated displacement
matches well with the measured displacement until
the peak displacement.
Figure 6 shows the comparison of the calculated
profiles of bending moments along pile with themeasured value. There are good agreements between
two solutions. It can be seen from the figure that
only the upper part of the pile deforms during thedynamic horizontal load test.
Using the same soil parameters as shown in Table
2, the static load displacement relation of the pile
was estimated using KWaveHybrid. Figure 9 shows
the comparison of the calculated static load displacement relation with the measured value. It canbe seen that the calculated result matches well withthe measured one.

600
500
400
300
200Analysis
Measured

1000051015

20253035

Horizontal displacement (mm)40Figure 9. Measured and calculated static load vs displacement.

In this paper, the results of alternating cyclic horizontal load tests and dynamic horizontal pile load
tests on driven open-ended steel pipe piles constructed for foundations of a bridge abutment at Shinotsu site have been presented and discussed
A good matching between the calculated andmeasured behaviours of the piles during dynamic
loading as well as during static loading was obtained.
The possibility of the use of dynamic horizontal
pile load test as an alternative method for the conventional static horizontal load testing was demonstrated.
230

REFERENCES
Kitiyodom, P., Matsumoto, T., Kojima, E., Kumagai, H. &Tomisawa, K. 2006. Analysis of static and dynamic horizontal load tests on steel pipe piles. Proceedings of 10th International Conference on Piling and Deep Foundations:690-699.
Kojima E., Kumagai, H., Kitiyodom, P., Matsumoto, T. &Tomisawa, K. 2006. Dynamic horizontal load tests on steelpipe piles having different sizes in the same construction
site and their analyses. Proceedings of 10th InternationalConference on Piling and Deep Foundations: 700-708.