• Journal of the Korean Society of Safety
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• v.18 no.1
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• pp.81-88
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• 2003

Recently, pile foundations were constructed in rough or soft ground than ground of well condition thus it is important that prediction of ultimate bearing capacity and calculation of proper safety factor applied pile foundation design. This study were performed to dynamic loading tests for the thirty two piles at four different construction sites and selected pile at three site were performed to static loading tests and then compare with measured value and value of static and dynamic loading tests. The load-settlement curve form the dynamic loading tests by CAPWAP was very similar to the results obtained from the static load tests. Based on dynamic and static loading tests, the reliability of pile-driving formula were analyzed and then suggested with proper safety factor for prediction of allowable bearing capacity in this paper.

• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.2
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• pp.124-133
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• 1997

Pile load test is good for estimating pile bearing capacity, but using this method is limited by time and cost required. Dynamic and static method is more convenient and economical, but confidence of estimated value by dynamic and static method are lower than that of pile load test. After being compared pile bearing capacity data obtained from pile load test with those of other two methods, the results from this study were summarised as follows. For allowable bearing capacity values greater than 175t per pile, bearing capacity acquired from static method was higher than that acquired from pile load test, whereas bearing capacity acquired from pile load test was higher than that acquired from static method for values under 175 per pile. It was that variance of bearing capacity was large when bearing capacity obtained by dynamic method was higher than 250t. Also bearing capacity based on dynamic method was higher than that based on pile load test. Allowable bearing capacity get from dynamic method suggested that carefull precautions are necessary in application for allowable bearing capacity values higher than 2S0ton per pile.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.10a
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• pp.390-397
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• 2002

In this study, static pile load tests with load transfer measurement for a pile socketed into weathered rocks were performed. Axial load transfers during static pile load test were measured and analyzed. Three large diameter piles socketed into weathered rock were behavior behaved as friction pile.

• Proceedings of the Korean Geotechical Society Conference
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• 1992.03a
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• pp.13-40
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• 1992

Static formulae based on limiting equilibrium theories often provide misleading predictions of pile bearing capacity in cohesionless soils due to the incorrect basic assumptions or oversimplification of actual soil conditions. Soil conditions prior to pile driving are significantly changed after pile installation and imposition of high stress levels. Therefore soi1 parameters at failure rather than those obtained at initial conditions should be used in application of static formulae. In this research. model pile test data were analyzed and compared with the predicted values obtained from the various static formulae. The results showed that the proper choice of soil parameters remarkably improve the reliability of static formulae.

• Journal of the Korean GEO-environmental Society
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• v.18 no.9
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• pp.11-18
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• 2017

Numerical analysis method for prediction of pile behaviour characteristics has widely been used in detail design process before construction because field static loading test requires high cost. However, the reliability verification of numerical analysis of result is not permitted compare with field test. In this study, to verify the numerical analysis results, pile behaviour prediction was compared with field static loading test results. For exact analysis of interaction between pile and ground, soil investigation and in-situ test such as boring, SPT and bore-hole shear test were performed before pile static loading test. During the static loading test, pile behaviour characteristics were analyzed under every loading condition. After static pile loading test, numerical analysis was carried out under same condition with static pile loading test. In the numerical analysis, to apply same loading condition with each loading condition in the field test and to compare with between the results of numerical analysis, the field test results for reliability were verified with the results of numerical analysis.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.03a
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• pp.249-258
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• 1999

Dynamic load and static load tests are performed on steel pipe piles and concrete piles at five construction sites in highway to compare the difference of load bearing mechanisms. At each site, one steel pile is instrumented with electric strain gages and dynamic tests are performed on the pile during installation. Damages of strain gages due to the installation are checked and static test is performed upon the same pile after two or seven days as well. It shows that load transfer from side friction to base resistance behaves somewhat differently according to the results of load-settlement analysis obtained from PDA and static load test. Initial elastic stage of load settlement curves of two load tests is almost similar. But after the yielding point, dynamic resistance of pile behaves more stiffer than static resistance, thus, dynamic load test result might overestimate the real pile capacity compared with static result. Analysis of gage readings shows that unit skin friction increases exponentially with depth. The skin friction is mobilized at the 1∼2m above the pile tip and contributes to the considerable side resistance. Comparison of side and base resistances between the measured value and the calculated value by Meyerhof's bearing capacity equation using SPT N value shows that the calculated base resistance is higher than the measured. Therefore, contribution of side resistance to total capacity shouldn't be ignored or underestimated. Finally, based upon the overall test results, a construction control procedure is suggested.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.03a
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• pp.107-141
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• 2000

Large diameter piles can be defined as piles with diameter of at least 0.76 m (2.5 ft). In bridge foundation, large diameter piles have been used as pier foundations and their use has been increased greatly. In this study, static pile load tests for large diameter piles peformed in Kwangan Grande Bridge construction site were introduced. Also, various sensor installation methods for several types of piles (that is, open-ended steel pipe pile, drilled shafts and socketed pipe piles), pipe axial load measuring method, load transfer analysis method and pile load test results (pile-head load - settlement curve, and pile axial load distribution curve along the pile depth) were introduced.

• Proceedings of the Korean Geotechical Society Conference
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• 1997.10a
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• pp.409-416
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• 1997

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.589-596
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• 2002

In this study, static pile load tests with load transfer measurement were accomplished in the field. Yield pile capacity (or ultimate pile capacity) determined by load-settlement-time relationship was determined and axial load transfer behavior was analyzed. In the test for the four test piles were behaved as end bearing pile but ratios of skin friction to total pile capacity were 27%∼33%.

• Geomechanics and Engineering
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• v.32 no.4
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• pp.453-462
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• 2023

Designing pile foundations subjected to the uplift forces such as buildings, oil platforms, and anchors is becoming increasingly concerned. In this paper, the conceptual design of a new type of driven piles called expanding pile is presented and assessed. Some grooves have been created in the shaft of the novel pile, and some moveable arms have been designed at the pile tip. At first, static analyses using the finite element method were performed to evaluate the effectiveness of the innovative pile on the axial bearing capacity. Then its effect on seismic behavior of moment frame is considered. Results show that the expanding arms were provided an ideal anchorage system because of the soil's noticeable locking-up effect increasing uplift bearing capacity. For example at the end of the static tensile loading procedure, displacement decrement up to 55 percent is observed. In addition, comparing the uplift bearing capacity of the usual and new pile with different lengths in sand and clay layers shows noticeable effect and sharp increase up to about two times especially in longer piles. Besides, a sensible reduction in the seismic response and the stresses in the beam-column connection between 23-36 percent are achieved that ensures better seismic behavior of the structures.