• Journal of the Korean GEO-environmental Society
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• v.5 no.3
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• pp.5-15
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• 2004

SIP has been widely used as a low noise and vibration piling method in Korea. But the quality control of SIP was not properly settled down and field workers did not fully understand the principle of SIP method. So not a less troubles were raised at construction site and bearing capacity was not fully mobilized. To settle these problems, Korea National Housing Corporation amended the construction and load test criteria of SIP in 2002. After load tests on the SIPs installed in field according to the new criteria, we found that the bearing capacity in field vs the design load ratio increased and bearing characteristics was enhanced than that installed by the former criteria. To consider the enhanced bearing characteristics in the pile design and determine the adequate design criteria, this paper analyzed the accuracy of design criterion which were commonly used in Korea comparing with the load test results. Analysis result shows that Meyerhof criteria(1976) properly simulates the bearing capacity of SIP installed by the new construction and load test criteria.

• Journal of the Korean GEO-environmental Society
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• v.22 no.6
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• pp.5-15
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• 2021

One of the construction methods applied as a pier foundation type is a single type cast-in-place pile. In applying a pile bent system as a foundation type, the main concern in designing can be said to secure the lateral bearing capacity of pile structure in system. In addition, to increase the rigidity of the pile structure, a method of increasing the lateral bearing capacity by reinforcing the pile structure with a casing has been used. However, although the reinforcing effect and appropriate reinforcing length of casing may vary depending on the soil conditions, there is insufficient studies on this, and for this reason, the entire pile structure in a pile bent system is reinforced with a casing, in the field. In addition, if the length of the entire pile is reinforced with a casing, it may lead to delays in construction and increase in construction costs. That is, in order to more effectively reinforce the pile structure with a casing, it is necessary to study the lateral bearing characteristics of the reinforced pile structure in system. And it should be determined the appropriate reinforcing length of the casing from the evaluated bearing characteristics. Therefore, in this study, the lateral bearing characteristics of piles applied with the reinforcing length of casing for each condition were evaluated through a numerical analysis. And, based on the analysis results, the appropriate reinforcing length of casing was proposed. As a result of the study, it was found that in order to effectively increase the lateral bearing capacity of pile structure, the reinforcing length of casing should be applied twice the influence range of the bending behavior of the pile, 1/β.

• Journal of the Korean Geotechnical Society
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• v.23 no.5
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• pp.101-110
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• 2007

In order to investigate the effect of the pile shape on the bearing capacity of non-displacement piles, a series of model pile load tests were performed using a calibration chamber and three model piles with different shape. Results of the model tests showed that the bearing capacity of tapered piles was affected by its taper angle as well as the stress states and relative density of soil. Based on the results of model pile load tests, a new design equation for estimation of the bearing capacity of non-displacement piles was proposed, and it takes into account the effect of the taper angles on the bearing capacity of non-displacement piles.

• Journal of the Korean GEO-environmental Society
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• v.4 no.1
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• pp.59-66
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• 2003

The environmental problem due to the pile driving, the use of low noise-vibration auger-drilled pilling is increasing to solve noise and vibration problem in pilling. Therefore, in Korea, SIP (Soil-Cement Injected Precast Pile) method is mainly used as auger-drilled pilling. However, a proper bearing capacity evaluation formula has not been suggested, yet. In order to improve and supplement this situation, direct shear tests between SIP pile skin interface and soil were executed under various conditions. Through the analysis of test results, skin resistance characteristics of SIP were investigated thoroughly. Also, the nonlinear unit skin resistance capacity model and relative parameters evaluation formula with SM, SC soil were suggested.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.11 no.4
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• pp.171-187
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• 1991

In the present study, an analytical solution method is proposed for the seismic design of cantilever sheet pile walls and anchored sheet pile walls used in harbor construction. Seepage pressures, together with a change in magnitudes of effective horizontal soil pressures, are included in the proposed solution method. Also, the Mononobe-Okabe analysis as well as the Westergaard and Matsuo-Ohara theory of hydrodynamic pressures is used in the proposed method. Further, the choice of values for safety factors is examined for the seismic design of anchored sheet pile walls, and the effects of various parameters(dredge line slope, differential in water levels, anchor position, and wall friction angle) on embedment depth, anchor force, and maximum bending moment are analyzed for anchored walls in dense sand deposits. In addition. the tables that could be used for preliminary seismic design of anchored walls in dense sands are presented. The proposed method deals with the sheet pile walls with free earth support.

• Journal of the Korean GEO-environmental Society
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• v.3 no.2
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• pp.15-21
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• 2002

Because of the environmental problem during the pile driving, the use of low noise-vibration auger-drilled pilling is increasing to solve noise and vibration problem in pilling. In Korea, SIP (Soil-Cement Injected Precast Pile) method is mainly used as auger-drilled pilling. But, a proper bearing capacity evaluation formula has not been suggested, yet. To improve and supplement this situation, direct shear tests between SIP pile skin interface and soil were executed under various conditions. Through the analysis of test results, skin resistance characteristics of SIP were investigated thoroughly. Also, the maximum unit skin resistance capacity evaluation formulae on SM, SC soil was suggested.

• Journal of the Korean Geosynthetics Society
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• v.10 no.1
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• pp.1-8
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• 2011

The problems like a deterioration of loading bearing capacity, an exaggeration of settlement and lateral deformation are able to be generated, meanwhile structures are built in soft ground. Top-Base method is belonged to a rigidity mat foundation method which is used to surface treatment of soft ground. This method makes an effect to increase the bearing capacity of foundation using friction force, and prevent the differential settlement. Further more, the In-Situ Top-Base method has advantages in the phase of economic effect by reduction of the construction cost and offers an expediency on construction comparing with precast products. This paper presents the way of the estimation of bearing capacity for In-Situ Top-Base method through field plate load test in soft ground. It utilizes the results to a future design by analyzing the properties in the existing study and designs through these analysis and calculating the top-base method's reasonable range.

• Journal of the Korean Geotechnical Society
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• v.34 no.7
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• pp.39-49
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• 2018

Jacked pile that involves the use of hydraulic jacks to press the piles into the ground is free from noise and vibration, and is possibly installed within a limited construction area. Thus, as an alternative to conventional pile driving methods, pile jacking could become widely accepted for the construction projects in urban area (e.g., reconstruction or remodeling construction projects). Great concern has arisen over the prediction of axially loaded jacked pile behavior. Against this background, a series of pile load tests were hence conducted on a jacked steel pipe pile installed in weathered zone (i.e., weathered soil and weathered rock). From the test results, base resistance and shaft resistance for each test condition were evaluated and compared with the values predicted by the previous driven pile resistance assessment method. Test results showed that the previous driven pile resistance assessment method highly underestimated both the base and shaft resistances of a jacked pile; differences were more obviously observed with the shaft resistance. The reason for this discrepancy is that a driven pile normally experiences a larger number of loading/unloading cycles during installation, and therefore shows significantly degraded stiffness of surrounding soil. Based on the results of the pile load tests, particular attention was given to the modification of the previous driven pile resistance assessment method for investigating the axially loaded jacked pile behavior.

• Geotechnical Engineering
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• v.22 no.3
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• pp.21-29
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• 2006

• Journal of the Korean Geotechnical Society
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• v.21 no.1
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• pp.115-121
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• 2005

At present, continual road constructions to connect from city to city are needed due to the geographical feature of Korea that about $70\%$ of the territory is mountainous area. Thus, the generation of large cut-slope has been inevitably formed. As a means of reinforcement on the cut-slope, in case of destructive disasters such as a snowstorm, pile embedment method is widely adopted. The pile embedment method is to resist possible move of soil by embedding piles from the surface to the immovable ground and then delivering the load from the piles to the immovable ground. In this study this writer analyzes the limitation of empirically used pile construction depth and its spacing through the numerical analysis. As a result, he suggests the most effective pile construction depth and space.