Case Pile Wave Analysis Program Research Articles

Comparison of Field Ultimate Capacity (Static and Dynamic Load Test) with the Analytic Design of Bored Pile in Granular Soil, Batam, Indonesia

A bored pile provides a large capacity obtained to toe and friction pile to support some loads such as axial, lateral, and tensile due to hydrostatic pressure or overturning moment. Static and dynamic load tests are often carried out to validate pile design before pile production in a project. This study aims to compare the ultimate capacity of the pile based on the result of static load test, dynamic load test, and pile design in granular soil of Batam, Indonesia, in which Chin-Kondner, Mazurkiewicz, Davisson, and Hansen 80% methods are utilized to obtain ultimate capacity (Qu) of static load test and dynamic test analysis apply Case Pile Wave Analysis Program (CAPWAP) method to gain ultimate capacity. The result analysis of the static load test of ultimate capacity using Chin-Kondner, Mazurkiewicz, Davisson, and Hansen 80% methods obtained results of 1379, 1300, 1375, and 1182 tons, respectively, with a Qu average of 1309 tons. A bearing capacity (RMX) of 1204 tons was obtained through a dynamic load test. Using the CAPWAP method based on the dynamic test, the ultimate bearing capacity (Ru) of 1248 tons was obtained. Analysis of pile design shows that the ultimate capacity of the bored pile in the granular soil of Batam, Indonesia, was 1157 tons. The Qu examination between field loading testing (1278.5 tons) and design pile foundation (1158 tons) was 9.4%.

Interpreting CAPWAP results for driven piles with corrections for setup and residual loads

Evaluation of pile capacity using dynamic testing and Case Pile Wave Analysis Program (CAPWAP) analysis has been shown to provide reasonable measurements of capacity and separates the shaft and tip resistance. It is a common method for verifying pile capacities; however, consideration of setup and presence of residual loads at the time of testing are necessary for interpreting the resistance distribution. A test pile program was conducted that included dynamic testing of piles at the end of initial driving and early restrikes to measure the rate of setup. The piles were instrumented to measure residual stresses. The shaft resistance and tip stiffness were interpreted from analyzing multiple blows and corrected for residual stresses. The results from CAPWAP were compared to measurements from static load tests. It was found that correcting CAPWAP results for residual loads resulted in better interpretation of the rate of setup and resistance distribution. Analyzing successive blows with CAPWAP provided an improved estimate of the tip load–movement curve by extrapolating the increase in tip capacity with penetration. The results demonstrate the importance of correcting CAPWAP results for residual stresses to gain a better understanding of the pile capacity, resistance distribution, and tip stiffness for design purposes.

Large-scale model tests of a single pile and two-pile groups for an offshore platform in sand

Estimating pile group efficiency for open-ended steel piles in small group arrangements is a challenging task for designers. This paper reports on the large-scale experimental campaign performed for the BorWin gamma offshore converter platform, which involved single piles and two-pile group systems on a scale of 1:10. The experimental works included installation, dynamic end-of-driving tests, dynamic restrike tests, and static load tests of a single pile and a pair of two-pile groups in densely compacted, artificially prepared homogeneous sand. The cone penetration test (CPT) profiles and the blow counts confirmed that the foundation systems are comparable to each other. The experimental results of the single pile system were compared with conventional design methods. Such comparison indicated that CPT-based methods and load-transfer methods are applicable at the considered model scale. The bearing capacity prediction obtained via the Case Pile Wave Analysis Program (CAPWAP) method is conservative with respect to the static capacity. A consistent setup effect can be detected by analyzing the complete dynamic loading session. The pile group efficiency for the given foundation system was found to be less than 1.0 at both very small and very large soil strains, while it equaled 1.0 at failure.

Case study of a driven pile foundation in diatomaceous soil. II: Pile installation, dynamic analysis, and pore pressure generation

Abstract This paper presents the results from a case study highlighting the difficulties of pile driving in diatomaceous soils. In the companion (first) paper to this article, results of an extensive laboratory and in situ testing program were presented while the results from pile driving and further analysis of field observations were presented herein. Unexpected high pile rebound (HPR) was observed during driving of a closed-end pipe pile, with refusal occurring at a depth of less than 5 m. Subsequent open-ended piles were thus driven. Piezometer and case pile wave analysis program (CAPWAP) data were collected during driving of both closed- and open-end piles. Piezometer data indicated that negative pore water pressures (PWPs) were generated while the closed-ended pile exhibited high rebound. Results from in situ tests indicated change in material stiffness and strong dilative tendencies near the depth of refusal. A hypothesis for observed behavior was proposed that considers the soil beneath the pile as a medium with an effectively infinite bulk modulus.

KOMPARASI KINERJA ALAT PILE DRIVING ANALYZER DAN SOFTWARE CAPWAP DALAM MENGHASILKAN DAYA DUKUNG ULTIMIT PONDASI TIANG

Buildings that stand on soft soil usually use a pile foundation. Testing the ultimate bearing capacity of pile foundations in the field is a Pile Driving Analyzer (PDA) tool. Besides being inexpensive to test, the results can also be known quickly. This tool is supported by a software called CAPWAP (CAse Pile Wave Analysis Program).In this paper, a performance comparison of the Pile Driving Analyzer (PDA) and CAPWAP (CAse Pile Wave Analysis Program) software will be presented in producing the ultimate bearing capacity of pile foundations. The results of both will be analyzed in such a way that the causes of the differences in the performance of the Pile Driving Analyzer (PDA) and the CAPWAP software are known.The results obtained show that the performance of the Pile Driving Analyzer (PDA) tool will not be optimal if the energy transferred to the pile foundation is too small. The energy given by the hammer when struck must be in the range of 1% - 2%, if it is smaller then the performance of the tool in producing the ultimate bearing capacity will not be representative. The difference in the ultimate bearing capacity between the PDA device and the CAPWAP software for energy transferred to the pile foundation (EMX) under the specified energy standard is 10.71% - 33.23%. Meanwhile, energy that meets the specified standards has a value between 0.24% - 1.80%.

ASSESSMENT TO THE PILE BEARING CAPACITY OF INJECTION PILE BASED ON PILE DRIVING ANALYZER AND RE-INJECTION TEST RESULTS (CASE: EASTKAL PENAJAM PROJECT)

Injection piling method was used as the main pile driving method at the three warehouses in the Eastkal Penajam project, Kalimantan, Indonesia. The sub-soil compositions are dominated by clay and sandy soil with very soft to medium consistencies. By using injection pile equipment, it is possible to measure the pile bearing capacity from the loading gauge. Since the soil is dominated by clay, the friction capacity overtime will be improved. For that purpose, the piles were re-injected again after 3, 10, 11, and 25 days. To establish the forecasting expression of pile bearing capacity enhancement for other piles, non-linear regression analysis was performed. To verify the result, pile driving analyzer (PDA) test for selected piles was carried out. The results from PDA test were further analyzed by using both direct fields reading in the PDA data logger and the Case Pile Wave Analysis Program (CAPWAP). A linear regression analysis was carried out to complete the blank data due to the field measurement limitation. In addition to the obtained field data, theoretical analysis of pile bearing capacity with Luciano Decourt method is carried out. From the comparisons of all data, it can be concluded that re-injection pile method provides the highest safety factor followed by PDA test, CAPWAP analysis, and theoretical design calculation with Luciano Decourt method.

A Load-Testing Program on Large-Diameter (66-Inch) Open-Ended and PSC-Instrumented Test Piles to Evaluate Design Parameters and Pile Setup

This paper presents the results from a pile load testing program for a bridge construction project at Chalmette, Louisiana. The load testing includes three 66-in. spun-cast post-tensioned open-ended cylinder piles and one 30-in. square prestressed concrete (PSC) pile driven at four different locations along the bridge site in clayey-dominant soil. Both cone penetration tests and soil borings/laboratory testing were used to characterize the subsurface soil conditions. All test piles (TP) were instrumented with strain gauges to measure the load distribution along the length of the TPs and to measure the side and tip resistances, separately. Dynamic load tests (DLT) were performed on all TPs at different waiting periods after pile installations to quantify the amount of setup (i.e., increase in pile resistance with time). Case Pile Wave Analysis Program (CAPWAP®) analyses were performed on the DLT data to calculate the resistance distributions along the TPs. A static load test was performed only on the PSC pile and statnamic load tests (SNLT) were conducted on both pile types. Design parameters such as the total stress adhesion factor, α, and the effective stress coefficient, β, were back-calculated. The α values ranged from 0.41 to 0.86, and the β values ranged from 0.13 to 0.29. The load test results showed that SNLT overestimated the tip resistance as compared with dynamic and static load tests. Moreover, the pile tip resistance was almost constant during the testing period, and setup was mainly attributed to increase in pile side resistance with time.

Development of analytical models to estimate the increase in pile capacity with time (pile setup) from soil properties

This paper presents the analyses of twelve prestressed concrete (PSC) instrumented test piles that were driven in different bridge construction projects of Louisiana in order to develop analytical models to estimate the increase in pile capacity with time or pile setup. The twelve test piles were driven mainly in cohesive soils. Detailed soil characterizations including laboratory and in situ tests were conducted to determine the different soil properties. The test piles were instrumented with vibrating wire strain gauges, piezometers, pressure cells that were monitored during the whole testing period. Several static load tests (SLTs) and dynamic load tests were conducted on each test pile at different times after end of driving (EOD) to quantify the magnitude and rate of setup. Measurements of load tests confirmed that pile capacity increases almost linearly with the logarithm of time elapsed after EOD. Case pile wave analysis program was performed on the restrikes data and was used along with the load distribution plots from the SLTs to evaluate the increase in skin friction capacity of individual soil layers along the length of the piles. The logarithmic linear setup parameter “A” for unit skin friction was calculated of the 70 individual clayey soil layers and was correlated with different soil properties such as undrained shear strength (Su), plasticity index, vertical coefficient of consolidation (cv), over consolidation ratio and sensitivity (St). Nonlinear multivariable regression analyses were performed, and three different empirical models are proposed to predict the pile setup parameter “A” as a function of soil properties. For verification, the subsurface soil conditions and setup information for additional 18 PSC piles collected from local database were used to compare the measured versus predicted “A” parameters from the proposed models, which showed good agreement.

Evaluation of pile capacity from CPT and pile setup phenomenon

Piles driven in cohesive soils usually experience a large increase in capacity over time, known as setup or freeze. This paper presents the field results of two test piles that were driven in two different locations of Louisiana to evaluate the pile setup behavior. Laboratory and in situ soil testings (cone penetration test, CPT) were conducted to characterize the subsurface soil properties. Several dynamic load tests (DLTs) and one static load test (SLT) were conducted on each test pile at different times after end of driving (EOD) to quantify the magnitude and rate of setup. The test pile in one site was instrumented with vibrating wire strain gages to calculate the load-distribution along the length of the pile during the static load test. With the aid of Case Pile Wave Analysis Program (CAPWAP®) analyses and load distribution plots from strain gages, skin friction and end-bearing capacities were measured separately. The load test results showed that the setup was mainly attributed to increase in skin friction with time and end-bearing capacity remained almost constant. The load test results also showed that setup behavior was more significant in soft cohesive soil. The pile capacity of one test pile was also evaluated using different CPT methods (such as Schmertmann, De Ruiter and Beringen, LCPC). The result showed that all the methods can estimate the pile capacity with good accuracy.

Experimental Study to Evaluate the Effect of Consolidation Behavior on Pile Setup

Abstract This paper presents the field experimental results of static load tests (SLTs) and dynamic load tests (DLTs) that were conducted on instrumented prestressed concrete (PSC) test piles to characterize the pile setup phenomenon for individual soil layers along the piles' length. For this purpose, three PSC piles were driven at a bridge construction site in Lake Charles, LA, that were tested at different times after installation. The piles were instrumented with sister bar strain gauges to measure the load transfer along the piles' length, and pressure cells and piezometers to measure the total stress, effective stress and excess pore water pressure (PWP) with time and hence the setup for different soil layers along the piles' length. Multilevel piezometers were installed in the surrounding soil to evaluate the spatial distribution of excess PWP and to measure the influenced zone caused by pile driving. The load tests showed that the side resistance increased by 129 %, 99 %, and 91 % for the three test piles during the last load test. The case pile wave analysis program (CAPWAP) analysis of the DLTs and the load distribution plots from SLTs were used to compute the resistance of individual soil layers along the piles with time. The results showed that the soil layers with low undrained shear strength and high value of generated excess PWP exhibited higher amount of setup; while soil layers with low permeability and low coefficient of consolidation exhibited higher rate of setup compared to other soil layers. The results also showed that setup increased at a higher rate before the dissipation of excess PWP and the rate became much slower after the end of dissipation process. The dissipation of excess PWP (or consolidation data) was used to quantify the setup by its contributing factors (i.e., consolidation and aging effect). The results showed that a majority of setups was because of the consolidation effect. The results of multilevel piezometers indicated that the influenced zone because of pile driving was almost 3B (B = pile width) radial distance from pile face.

Case studies to demonstrate challenges of driven piles on rock

In Wyoming, pile foundations for bridges are often driven on rock materials because of the state’s shallow bedrock stratigraphy. Unfortunately, no static analysis methods are currently available for estimating the resistance of these driven piles. In this paper, two recently completed bridge projects (the Owl Creek and Woods Wardell sites) on steel H-piles in Wyoming are explicitly presented, and data from three past projects are included to highlight the limited knowledge and challenges pertaining to the present design and construction practices. Static analysis methods were used to estimate the geotechnical resistances of these piles. The wave equation analysis program and the case pile wave analysis program were used to verify their performances during construction. Structural capacities of these piles were also calculated. The results of the studies show that the static analysis methods and structural analyses yield inconsistent pile resistance estimations. Recommendations in terms of pile bracing and embedded pile length are proposed to predict better the resistances of piles on soft rock.

Integration of construction control and pile setup into load and resistance factor design of piles

Regionally developed Load and Resistance Factor Design (LRFD) recommendations for bridge pile designs are enhanced by integrating the construction control capability of dynamic analysis methods and the recently developed pile setup quantification method in the calibration process. Using a high quality, electronic Pile LOad Test (PILOT) database and 10 recently completed full-scale pile tests, resistance factors were developed using a reliability theory for a locally calibrated static analysis method and two dynamic analysis methods: the Wave Equation Analysis Program (WEAP) and the CAse Pile Wave Analysis Program (CAPWAP). Pile design efficiency was improved by minimizing the discrepancy between design and field pile resistances through a proposed probability-based construction control method. The efficiency of bridge foundations was further increased by incorporating the economic advantages of pile setup into the LRFD recommendations. Compared with recommendations made by Paikowsky et al. (2004), Canadian Engineering Society (2006) and American Association of State Highway and Transportation Officials (2003), regionally-calibrated resistance factors were improved.

SPT 에너지효율 측정 롯드를 이용한 매입말뚝의 선단지지력 예측

국내외에서 널리 사용 중인 표준관입시험(Standard Penetration Test, SPT)은 작업의 용이성, 다양한 지반정수와 강도정수를 결정방법 등의 장점을 지니고 있다. 이러한 SPT 수행시에 발생하는 해머 에너지는 N치의 산정 및 보정에 매우 중요한 영향인자가 된다. SPT시험시 해머 타격에 의하여 롯드로 응력파가 전달되는 현상이 말뚝 항타 시에 발생하는 현상과 동일하다하여 SPT에 PDA장비를 적용하여 관입에너지를 측정하는 방법이 개발되어 사용 중에 있다. 본 연구에서는 SPT 롯드를 말뚝으로 가정하여 SPT 에너지 효율 측정롯드를 SPT시험과 동적콘관입시험에 적용하여 얻어진 힘과 속도의 파형을 매칭기법(CAPWAP, CAse Pile Wave Analysis Program) 분석을 수행하여 매입말뚝에 대한 극한선단지지력을 예측하는 기법을 제안하였다. 또한, SPT 에너지 효율 측정롯드에서 예측된 선단지지력과 실물 말뚝정재하시험을 통하여 산정된 선단지지력을 비교분석하였다. 연구결과를 토대로 SPT나 동적콘관입시험을 통하여 매입말뚝의 지지력을 간편하게 예측할 수 있는 경험식을 제시하였다. The standard penetration test (SPT) has been widely used because of its usability, economy, and many correlations with soil properties among other factors. In SPT, hammer energy is an important factor to evaluate and calibrate N values. To measure hammer energy, an instrumented SPT rod was developed considering that stress waves transferring on rods during SPT driving are the same as stress waves transferring on piles due to pile driving. Using this idea, an instrumented SPT rod with a pile driving analyzer was applied as a pile capacity prediction tool in this study. In order to evaluate this method, SPT and dynamic cone tests with the instrumented SPT rod were conducted and also 2 pile load tests were performed on pre-bored steel pipe piles at the same test site. End bearings were predicted by CAPWAP analysis on force and velocity waves from dynamic cone penetration tests and SPT. Comparing these predicted end bearings with static pile load tests, a new prediction method of the end bearing capacity using the instrumented SPT rod was proposed.

Closure to “Pile Setup in Cohesive Soil. I: Experimental Investigation” by Kam W. Ng, Matthew Roling, Sherif S. AbdelSalam, Muhannad T. Suleiman, and Sri Sritharan

Closure to “Pile Setup in Cohesive Soil. I: Experimental Investigation” by Kam W. Ng, Matthew Roling, Sherif S. AbdelSalam, Muhannad T. Suleiman, and Sri Sritharan

Dynamic soil parameters and Case damping for high-capacity long H-piles

Uncertainty exists in signal-matching techniques. The quake and damping obtained may not be the actual response of the soil. In this paper, the final sets, strain gauge readings, pile driving analyzer, and Case pile wave analysis program of 12 high-capacity long H-piles at the end of initial driving as well as two of them at restrike are studied. Measured and deduced data show that the soil response underneath the pile toes has limited movement and yielding despite the piles being set using very heavy hammer rams and large ram drops. The quake and damping decrease with increased shearing strain and shearing stress, but are influenced by pile whipping, rebounded stress wave, and load-transfer mechanism. The lumped Case damping factor decreases with increased side resistance to total resistance ratio. This factor can decrease or increase with time due to changes in the load-transfer mechanism after set-up, thus affecting the proportion of viscous damping of soil along the pile shaft and at the pile toe. A Case damping model is proposed that approximates the lumped Case damping factor as the sum of hysteretic damping of the pile and viscous damping of the surrounding soil. The effects of variation in load distribution and set-up along the pile shaft in layered soils and incomplete mobilization of soil at the pile toe on the Case damping factors are explained.

Study of Pile Setup

A new growth-rate–based model is proposed for pile setup prediction. Together with the Skov–Denver model, it has been developed for southern Louisiana clayey soils by using the pile driving analyzer database provided by the Louisiana Department of Transportation and Development from the construction of Phase 1B of the LA-1 relocation project in Leeville, Louisiana. The data used for this study include 115 restrike records from 95 production piles and the records of restrikes, static, and statnamic load tests of nine fully instrumented test piles. The models were developed with the average unit skin friction or normalized pile shaft resistances, which were obtained from the case pile wave analysis program analyses and the pile load test results. The growth-rate–based model can predict the capacity increase with time and can estimate the ultimate pile resistance. For the Skov–Denver model, selection of the reference time was investigated and distribution of the setup parameters A was studied. Predictability of the rate-based model was evaluated and validated by comparing it with the conventional Skov–Denver model.

Reliability of Pile Driving Analyzer for Determination of Axial Capacity of Large-Diameter Cylindrical Pile

A case history involving the design and construction of the water pier foundations for a fixed high-level precast segmental bridge over the Shrewsbury River in Monmouth County, New Jersey, is presented. The water pier foundations are supported on 54-in. prestressed open-ended concrete cylindrical piles with a 6.0-in. wall thickness. Design concepts for cylindrical piles are outlined. Results of the pile load testing program on one pile are presented. The reliability of the pile driving analyzer and case pile wave analysis program data are evaluated based on the result of the static load test. Installation procedures and load-testing programs of the open-ended cylindrical piles are discussed. A comparison of case histories of large-diameter cylindrical piles is presented, drawing from a similar experience of a former project. Recommendations for design, construction, and dynamic testing of large-diameter cylindrical piles are made.

Measured Soil Setup of Steel HP Piles from Windsor Bypass Project in North Carolina

Restrikes were performed on piles driven for a North Carolina Department of Transportation highway construction project to verify the required bearing capacity, which was not achieved at the end of initial drive (EOID). Driving records of 98 piles with both initial driving and restrike blow counts and hammer stroke were collected. Six of these piles were driven with a pile-driving analyzer, and Case Pile Wave Analysis Program analysis was performed on the collected pile-driving analyzer data. All piles were steel H-pile piles, and the restrikes were done within 144 h after the EOID. The pile bearing capacities of both EOID and restrike were estimated from the blow counts and hammer stroke using the GRL Engineers Inc. Wave Equation Analysis Program, Version 2005. Soil setup ratios of these piles were computed and statistically analyzed to find a reliable setup ratio that can be applied to the bearing capacity obtained at the EOID of the remaining piles in this project to ensure the required bearing without a restrike. The mean soil setup ratio of all piles in this project was estimated at 1.41. However, no setup ratio can be applied to the EOID bearing capacity of an individual pile with a 98% confidence level. Restrike of every pile is required to ensure this level of confidence. A setup ratio of 1.10 can be applied with a 90% confidence level. The setup ratios vary greatly from pile to pile. Soil setup occurs rapidly after EOID in this project. Soil setup is more significant in loose or soft soils than in dense or stiff soils.

Knowledge-based design and construction of driven piles

Specified numbers of static load tests (e.g., 1% of working piles) and dynamic tests (e.g., 10% of working piles) are often required in Hong Kong to verify the reliability of driven piles for every single project. In this research, a pile database, the Hong Kong Driven Pile Database, is developed: (a) to systematically compile historic driven pile data, which include pile data, soil investigation data, static load test results, dynamic test results and case pile wave analysis program results; (b) to provide data for reliability evaluation of design methods; (c) to assist in design of future foundation projects based on past experience; and (d) to learn from past failures. The database contains information on 1514 piles, including 308 static load test piles. In this paper, the basic information of the database such as the sources of piling data and the major components of the database is first described. Then the reliability of five termination criteria for piledriving control is evaluated against the pile test information in the database. Subsequently, a performance evaluation of three driving-stress analysis methods is conducted based on information in the database. Finally, to demonstrate possible knowledge-based pile design and construction using the database, a design example is presented illustrating how the database can be used to assist in the early stage of pile design for a future project. The information on hammers, range of final set values and resulting pile performance in case histories of similar projects can be used as a reference for the engineer to expedite design for new projects. The engineer can also learn from the past pile failures contained in the database.

각종 항타공식에 의한 말뚝의 허용지지력 연구

말뚝에 대한 지지력 평가는 재하시험에 의한 결과를 이용하는 것으로부터 정.동력학적 공식등 다양한 방법들이 사용되고 있다 최근의 국내 조사에 의하면 표준관입시험의 N치에 기초한 Meyerhof공식이 설계단계에서 빈번하게 사용되는 것으로 보인다. 본 연구에서는 국내에서 실시된 다수의 정 동재하시험자료를 가지고 말뚝기초 설계에 사용되는 이론식을 실측값과의 비교를 통해 각종 이론식에 의한 말뚝의 허용지지력 추정의 신뢰성을 알아 보고자 하였다 또한, 경시효과를 고려한 경우 말뚝의 지지력에 미치는 영향에 대해서도 연구가 이루어졌다 본 연구를 통해 얻은 주요 결과로는 Davisson 방법을 기준으로 정도를 평가한 결과, Terzaghi & Peck > Chin > Meyerhof > 수정 Meyerhof 방법순으로 기준값에 근접하였으며 동재하시험결과는 항타공식 중 수정 Engineering News 공식이 가장 실측치에 근접한 결과를 주었으나 이는 해머 효율의 불확실성이라든가 변수의 자체특성, 경시효과등이 고려된 경우에는 다른 결과를 줄 수도 있을 것으로 판단되며, 경시효과를 고려한시험 결과 선단지지력에 비해 주면마찰력이 뚜렷하게 증가하였는데 항타시 대비 주면마찰력은 평균 약 2배정도 증가하였고 Engineering News,수정 Engineering News, Hiley, Danish, Gates, CAPWAP 해석시에 대한 7일의 경시효과를 고려한 관계시은 각각 <TEX>$Q_{u(Restrike)} / Q_{u(EOID)} = 0.98t_{0.1}$</TEX> , <TEX>$0.98t_{0.1}$</TEX>, <TEX>$1.17t_{0.1}$</TEX>, <TEX>$0.88t_{0.1}$</TEX>, <TEX>$0.89t_{0.1}$</TEX>, <TEX>$0.97t_{0.1}$</TEX>.과 같은 결과를 주었다. The estimation of pile bearing capacity is important since the design details are determined from the result. There are numerous ways of determining the pile design load, but only few of them are chosen in the actual design. According to the recent investigation in Korea, the formulas proposed by Meyerhof based on the SPT N values are most frequently chosen in the design stage. In the study, various static and dynamic formulas have been used in predicting the allowable bearing capacity of a pile. Further, the reliability of these formulas has been verified by comparing the perdicted values with the static and dynamic load test measurements. Also, in most cases, these methods of pile bearing capacity determination do not take the time effect consideration, the actual allowable load as determined from pile load test indicates severe deviation from the design value. The principle results of this study are summarized as follows : As a result of estimate the reliability in criterion of the Davisson method, t was showed that Terzaghi & Peck >Chin>Meyerhof > Modified Meyerhof method was the most reliable method for the prediction of bearing capacity. Comparisons of the various pile-driving formulas showed that Modified Engineering News was the most reliable method. However, a significant error happened between dynamic bearing capacity equation was judged that uncertainty of hammer efficiency, characteristics of variable, time effect etc... was not considered. As a result of considering time effect increased skin friction capacity higher than end bearing capacity. It was found out that it would be possible to increase the skin friction capacity 1.99 times higher than a driving. As a result of considering 7 day's time effect, it was obtained that Engineering news, Modified Engineering News, Hiley, Danish, Gates, CAPWAP(CAse Pile Wave Analysis Program) analysis for relation, repectively, <TEX>$Q_{u(Restrike)} / Q_{u(EOID)} = 0.98t_{0.1}$</TEX> , <TEX>$0.98t_{0.1}$</TEX>, <TEX>$1.17t_{0.1}$</TEX>, <TEX>$0.88t_{0.1}$</TEX>, <TEX>$0.89t_{0.1}$</TEX>, <TEX>$0.97t_{0.1}$</TEX>.