Factors Influencing Pile Friction Bearing Capacity: Proposing a Novel Procedure Based on Gradient Boosted Tree Technique

In geotechnical engineering, there is a need to propose a practical, reliable and accurate way for the estimation of pile bearing capacity. A direct measure of this parameter is difficult and expensive to achieve on-site, and needs a series of machine settings. This study aims to introduce a process for selecting the most important parameters in the area of pile capacity and to propose several tree-based techniques for forecasting the pile bearing capacity, all of which are fully intelligent. In terms of the first objective, pile length, hammer drop height, pile diameter, hammer weight, and N values of the standard penetration test were selected as the most important factors for estimating pile capacity. These were then used as model inputs in different tree-based techniques, i.e., decision tree (DT), random forest (RF), and gradient boosted tree (GBT) in order to predict pile friction bearing capacity. This was implemented with the help of 130 High Strain Dynamic Load tests which were conducted in the Kepong area, Malaysia. The developed tree-based models were assessed using various statistical indices and the best performance with the lowest system error was obtained by the GBT technique. The coefficient of determination (R2) values of 0.901 and 0.816 for the train and test parts of the GBT model, respectively, showed the power and capability of this tree-based model in estimating pile friction bearing capacity. The GBT model and the input selection process proposed in this research can be introduced as a new, powerful, and practical methodology to predict pile capacity in real projects.

Download Full-text

Bi-Directional Static Load Tests of Pile Models

Applied Sciences ◽

10.3390/app10165492 ◽

2020 ◽

Vol 10 (16) ◽

pp. 5492

Author(s):

Michał Baca ◽

Włodzimierz Brząkała ◽

Jarosław Rybak

Keyword(s):

Bearing Capacity ◽

Static Load ◽

Load Testing ◽

Pile Capacity ◽

Pile Shaft ◽

Load Tests ◽

S Curve ◽

Definition Of ◽

Standard Tests ◽

Static Load Testing

This work examined a new method of bi-directional static load testing for piles, referencing the Osterberg test. Measurements were taken, on a laboratory scale, using six models of piles driven into a box filled with sand. This method allowed for separate measurements of pile base and pile shaft bearing capacities. Based on the results, the total pile bearing capacity and equivalent Q–s diagrams were estimated. The results obtained show that the structure of the equivalent curve according to Osterberg is a good approximation of the standard Q–s curve obtained from load tests, except for loads close to the limit of bearing capacity (those estimates are also complicated by the inapplicability and ambiguity of a definition of the notion of limit bearing capacity); the equivalent pile capacity in the Osterberg method represents, on average, about 80% of the capacity from standard tests.

Download Full-text

Research on the Relationship between SPT and the Ultimate Vertical Bearing Capacity of Jacked Pile in Shenyang District

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.71-78.3308 ◽

2011 ◽

Vol 71-78 ◽

pp. 3308-3311

Author(s):

Xiang Ruan ◽

Ren Yu Zuo

Keyword(s):

Bearing Capacity ◽

Empirical Formula ◽

Standard Penetration Test ◽

Penetration Test ◽

Initial Stage ◽

Engineering Requirement ◽

Load Tests ◽

Vertical Bearing ◽

Vertical Bearing Capacity ◽

The Relationship

Though the wide applications of jacked pile in engineering in Shenyang district, the problem is also exist in engineering for the capacity of the jacked pile is hard to account. The relationship between the standard penetration test and the ultimate vertical bearing capacity of jacked pile is established in this paper; also an empirical formula is put forward for calculating the ultimate vertical bearing capacity of the jacked pile in this district with blow count of standard penetration test (SPT). The engineering examples indicated that the empirical formula is feasible because the calculating bearing capacity of the silent pipe pile is coincided with the static load tests. The calculated results satisfy the engineering requirement andt can be concluded that the method is also convenient to choose the diameter and length of the pile during the initial stage of design.

Download Full-text

PROPOSTA DE APLICAÇÃO DE RESULTADOS DE SONDAGENS COM MARTELO LEVE (DPL) NO CAMPO EXPERIMENTAL DA UNIFOR EM PROJETOS DE FUNDAÇÕES PARA PEQUENAS CARGAS [ Proposal for the Application of Dynamic Probing Light (DPL) Results in the Experimental Field of UNIFOR in Foundations Projects for Small Loads ]

REEC - Revista Eletrônica de Engenharia Civil ◽

10.5216/reec.v14i2.47577 ◽

2018 ◽

Vol 14 (2) ◽

Author(s):

Marcos Fábio Porto de Aguiar ◽

Fernando Feitosa Monteiro ◽

Francisco Heber Lacerda de Oliveira ◽

Yago Machado Pereira de Matos

Keyword(s):

Bearing Capacity ◽

Standard Penetration Test ◽

Coefficient Of Determination ◽

Deep Foundations ◽

Penetration Test ◽

In Situ Tests ◽

Foundation Design ◽

Experimental Field

RESUMO: Em meio aos diversos métodos utilizados no Brasil para determinação da capacidade de carga de fundações, a grande maioria parte do índice de resistência à penetração (NSPT). Para o caso de pequenas edificações, devido a fatores geralmente econômicos, a experiência ou a prática regional costumam prevalecer. Sendo assim, são elaborados, muitas vezes, projetos sem um procedimento de cálculo fundamentado em parâmetros comprovados por ensaios geotécnicos, podendo ocasionar problemas na edificação, como recalques excessivos, ou, até mesmo, comprometer a segurança da estrutura. Dessa forma, técnicas mais simples e de baixo custo, como o DPL (Dynamic Probing Light), podem ser uma opção para situações de pequenas cargas, viabilizando projetos fundamentados em ensaios in situ. Partindo de investigações com o DPL, este trabalho tem o objetivo de dimensionar fundações superficiais e profundas para edificações de pequeno porte através de algumas das principais metodologias disponíveis na literatura e verificar a sua eficiência. Por meio de resultados de campanhas de sondagens SPT (Standard Penetration Test) e DPL no campo experimental da Universidade de Fortaleza (UNIFOR), determinou-se a capacidade de carga de fundações superficiais e profundas fazendo aplicação dos índices NSPT e NSPT equivalente obtido pela correlação com o DPL. Identificou-se que essa correlação apresentou coeficiente de determinação satisfatório entre os parâmetros obtidos nos ensaios SPT e DPL para o terreno em questão, mostrando-se o DPL ser uma alternativa pertinente, em termos técnicos para projetos de fundações de obras de pequeno porte.ABSTRACT: Among the various methods used in Brazil of the determination of the bearing capacity on foundations, most part uses the standard penetration resistance (NSPT). For small constructions, due to economic factors generally, experience or regional practice usually prevails. Thus, projects without a reasoned calculation procedure in parameters supported by geotechnical tests are often designed, and may cause problems in the building, as excessive settlements, or even compromise the safety of the structure. In this way, simple and low cost techniques such as DPL (Dynamic Probing Light) may be an option for small loads situations, enabling projects based on in situ tests. This paper proposes to calculate the dimensions of shallow and deep foundations for small constructions and check its efficiency using DPL tests. Through the results of SPT (Standard Penetration Test) and DPL tests in the experimental field of the University of Fortaleza (UNIFOR), the determination of the bearing capacity in shallow and deep foundations was done using NSPT index and equivalent NSPT index obtained by the correlation with DPL. A correlation with satisfactory coefficient of determination was obtained between SPT and DPL tests parameters for the analyzed field, showing up the DPL as an appropriate alternative in technical terms for foundation design of small constructions.

Download Full-text

Axial compressive capacity of driven piles in sand: a method including post-driving residual stresses

Canadian Geotechnical Journal ◽

10.1139/t00-104 ◽

2001 ◽

Vol 38 (2) ◽

pp. 364-377

Author(s):

Ahmed Shlash Alawneh ◽

Osama Nusier ◽

Abdullah I Husein Malkawi ◽

Mustafa Al-Kateeb

Keyword(s):

Residual Stresses ◽

Bearing Capacity ◽

Relative Density ◽

Friction Angle ◽

Accurate Estimate ◽

Driven Piles ◽

Pile Capacity ◽

Shaft Resistance ◽

Load Tests ◽

Pile Load Tests

In this paper, empirical formulae were developed between the well-known pile bearing capacity factors (Nq and β) and parameters which include friction angle of sand, relative density, average effective vertical stress, and deformability of the soil below the pile toe. The developed empirical formulae were totally based on a database comprised of 28 well-documented compressive pile load tests collected exclusively from geotechnical literature. The actual measurements of shaft and end-bearing resistances of each pile in the database were adjusted to account for post-driving residual loads. Calculation of pile bearing capacity factors (Nq and β) was based on the adjusted shaft and end-bearing resistances rather than the actual unadjusted measured resistances for residual loads. Comparison of predicted and measured compressive capacity of an independent database comprised of 18 pile load tests showed that the developed formulae yield a reasonably accurate estimate of compressive pile capacity in cohesionless soils.Key words: driven piles, residual load, toe resistance, shaft resistance.

Download Full-text

Accuracy of pile capacity assessment on the basis of piling reports

E3S Web of Conferences ◽

10.1051/e3sconf/20199704029 ◽

2019 ◽

Vol 97 ◽

pp. 04029 ◽

Cited By ~ 2

Author(s):

Jakub Rainer

Keyword(s):

Bearing Capacity ◽

Operational Reliability ◽

Driven Piles ◽

Safety Factors ◽

Pile Capacity ◽

Current Assessment ◽

Proper Design ◽

Foundation Pile ◽

Load Tests ◽

Pile Load Tests

Current assessment of foundation pile bearing capacity during driving may considerably improve operational reliability in terms of loads to be transferred. It also enables proper design and trial examinations by focusing attention on piles with atypical driving characteristics. The paper presents the method applicable to assess the bearing capacity of prefabricated driven piles and provides analysis of likelihood of this assessment by the example of numerous prefabricated piles documented by piling reports and results of static pile load tests to the extent allowing to determining the limit bearing capacity. The results attained could be the basis to determine respective safety factors in pile design based on driving resistance analysis.

Download Full-text

Bearing capacity of rigid piles under eccentric and inclined loads

Canadian Geotechnical Journal ◽

10.1139/t85-040 ◽

1985 ◽

Vol 22 (3) ◽

pp. 267-276 ◽

Cited By ~ 37

Author(s):

G. G. Meyerhof ◽

V. V. R. N. Sastry

Keyword(s):

Bearing Capacity ◽

Soft Clay ◽

Horizontal Load ◽

Soil Pressure ◽

Pile Capacity ◽

Inclined Loads ◽

Pure Moment ◽

Load Tests ◽

Rigid Model ◽

Test Pile

The ultimate bearing capacity of instrumented vertical single rigid model piles in homogeneous loose sand and soft clay under vertical eccentric and central inclined loads has been investigated. The results of these load tests provide a more realistic lateral soil pressure distribution on the pile shaft and better theoretical estimates of pile capacity under pure moment and under horizontal load. For intermediate eccentricities and inclinations of the load, the bearing capacity can be obtained from simple interaction relationships between the axial load and moment capacities and between the axial and horizontal load capacities, respectively. The influence of lateral soil pressures due to installation of displacement piles in clay is examined in relation to the ultimate load of the pile. The analyses are compared with the results of model tests and some field case records. Key words: bearing capacity, clay, eccentric loading, horizontal load, instrumentation, model test, pile, sand.

Download Full-text

Ultimate pile capacity in layered soil under eccentric and inclined loads

Canadian Geotechnical Journal ◽

10.1139/t85-051 ◽

1985 ◽

Vol 22 (3) ◽

pp. 399-402 ◽

Cited By ~ 4

Author(s):

G. G. Meyerhof ◽

R. D. Purkayastha

Keyword(s):

Bearing Capacity ◽

Layered Soil ◽

Clay Layer ◽

Pile Groups ◽

Eccentric Load ◽

Pile Capacity ◽

Foundation Model ◽

Load Tests ◽

Rigid Model ◽

Single Piles

The ultimate bearing capacity of rigid model piles and pile groups in layered soil consisting of clay overlying sand has been investigated for various combinations of eccentricity and inclination of load and with varying thicknesses of clay layer. The effect of eccentricity and inclination of the load and thickness ratios of clay layer to pile embedment in the sand on the bearing capacity can be represented by simple interaction relationships to estimate the ultimate load. The results of load tests on single model piles and freestanding pile groups are presented in the form of polar bearing capacity diagrams and are compared with the theoretical estimates. The thickness of clay layer on the sand is found to have a significant influence on the bearing capacity of single piles and pile groups. Key words: pile foundation, model test, layered soil, eccentric load, inclined load, sand, clay, analysis, bearing capacity.

Download Full-text

Determination of Soil Bearing Capacity from Spectral Analysis of Surface Wave Test, Standard Penetration Test and Mackintosh Probe Test

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.g5006.059720 ◽

2020 ◽

Vol 9 (7) ◽

pp. 340-346

Keyword(s):

Spectral Analysis ◽

Surface Wave ◽

Bearing Capacity ◽

Cost Effective ◽

Standard Penetration Test ◽

Ultimate Bearing Capacity ◽

Coefficient Of Determination ◽

Penetration Test ◽

Investigation Methods ◽

Probe Test

Spectral Analysis of Surface Wave (SASW) method is one of soil investigation methods which promotes cost-effective and less time-consuming procedures, apart form of its non-destructive nature. This study aims to determine the soil ultimate bearing capacity obtained from the SASW method by using Ali Keceli’s equation for sandy silt soil. The finding in terms of bearing capacity is then compared to the Standard Penetration Test (SPT) and Mackintosh Probe (MP) results. All the tests were conducted at seven different locations. It is found that there is no 1:1 relationship between the bearing capacity obtained from SPT and SASW although the pattern of the trendline is similar. However, the pattern of the trendline captured is not as similar as SPT for MP and SASW. The coefficient of determination (R2 ) between SPT and SASW varies from 0.74 to 0.95 and the R2 between the MP and SASW varies from 0.43 to 0.77. The overall R 2 found for SPT and SASW is 0.87 and 0.74 for MP and SASW in all locations. For the comparison with SPT and MP, SASW is well-correlated with SPT and moderately with MP. From this study, it can be concluded that SASW has the potential to determine the ultimate bearing capacity of soil as an alternative to SPT and MP tests.

Download Full-text

Driven cast-in-situ pile capacity: insights from dynamic and static load testing

Canadian Geotechnical Journal ◽

10.1139/cgj-2020-0630 ◽

2021 ◽

Author(s):

Kevin N. Flynn ◽

Bryan A. McCabe

Keyword(s):

Dynamic Load ◽

Shear Stresses ◽

Load Testing ◽

Pile Capacity ◽

Compression Load ◽

Shaft Resistance ◽

Pile Installation ◽

Cast Concrete ◽

Load Tests

Driven cast-in-situ (DCIS) piles are classified as large displacement piles. However, the use of an oversized driving shoe introduces additional complexities influencing shaft resistance mobilisation, over and above those applicable to preformed displacement piles. Therefore, several design codes restrict the magnitude of shaft resistance in DCIS pile design. In this paper, a series of dynamic load tests was performed on the temporary steel driving tubes during DCIS pile installation at three UK sites. The instrumented piles were subsequently subjected to maintained compression load tests to failure. The mobilised shear stresses inferred from the dynamic tests during driving were two to five times smaller than those on the as-constructed piles during maintained load testing. This was attributed to soil loosening along the tube shaft arising from the oversized base shoe. Nevertheless, the radial stress reductions appear to be reversible by the freshly-cast concrete fluid pressures which provide lower-bound estimates of radial total stress inferred from the measured shear stresses during static loading. This recovery in shaft resistance is not recognised in some European design practices, resulting in conservative design lengths. Whilst the shaft resistance of DCIS piles was underpredicted by the dynamic load tests, reasonable estimates of base resistance were obtained.

Download Full-text