Determination of soil parameters from in-situ tests. Report of the organiser, specialty session No 5

1979 ◽  
Vol 16 (3) ◽  
pp. 73
Keyword(s):  
Soil Parameters ◽  
In Situ Tests

scholarly journals Laboratory and In Situ Determination of Hydraulic Conductivity and Their Validity in Transient Seepage Analysis

Water ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1131
Author(s):  
Soonkie Nam ◽  
Marte Gutierrez ◽  
Panayiotis Diplas ◽  
John Petrie
Keyword(s):  
Hydraulic Conductivity ◽  
Field Measurements ◽  
Natural Soil ◽  
In Situ Tests ◽  
Seepage Analysis ◽  
Soil Deposits ◽  
Seepage Modeling ◽  
Sample Disturbance

This paper critically compares the use of laboratory tests against in situ tests combined with numerical seepage modeling to determine the hydraulic conductivity of natural soil deposits. Laboratory determination of hydraulic conductivity used the constant head permeability and oedometer tests on undisturbed Shelby tube and block soil samples. The auger hole method and Guelph permeameter tests were performed in the field. Groundwater table elevations in natural soil deposits with different hydraulic conductivity values were predicted using finite element seepage modeling and compared with field measurements to assess the various test results. Hydraulic conductivity values obtained by the auger hole method provide predictions that best match the groundwater table’s observed location at the field site. This observation indicates that hydraulic conductivity determined by the in situ test represents the actual conditions in the field better than that determined in a laboratory setting. The differences between the laboratory and in situ hydraulic conductivity values can be attributed to factors such as sample disturbance, soil anisotropy, fissures and cracks, and soil structure in addition to the conceptual and procedural differences in testing methods and effects of sample size.

scholarly journals Neural networks and principle component analysis approaches to predict pile capacity in sand

2018 ◽  
Vol 149 ◽  
pp. 02025 ◽  
Author(s):  
A Benali ◽  
A Nechnech ◽  
B Boukhatem ◽  
M N Hussein ◽  
M Karry
Keyword(s):  
Neural Networks ◽  
Bearing Capacity ◽  
Driven Piles ◽  
In Situ Tests ◽  
Pile Capacity ◽  
Significant Development ◽  
Pca Method ◽  
Main Component

Determination of pile bearing capacity from the in-situ tests has developed considerably due to the significant development of their technology. The project presented in this paper is a combination of two approaches, artificial neural networks and main component analyses that allow the development of a neural network model that provides a more accurate prediction of axial load bearing capacity based on the SPT test data. The retropropagation multi-layer perceptron with Bayesian regularization (RB) was used in this model. This was established by the incorporation of about 260 data, obtained from the published literature, of experimental programs for large displacement driven piles. The PCA method is proposed for compression and suppression of the correlation between these data. This will improve the performance of generalization of the model.

scholarly journals Determination of p-y curves for offshore piles based on in-situ soil investigations

2018 ◽  
Vol 219 ◽  
pp. 05003
Author(s):  
Kamila Międlarz ◽  
Lech Bałachowski
Keyword(s):  
Field Tests ◽  
Soil Parameters ◽  
Lateral Loads ◽  
Cohesionless Soils ◽  
In Situ Tests ◽  
Soil Stiffness ◽  
Soil Response ◽  
Direct Design ◽  
Offshore Piles

Offshore piles are subjected to complex loads with considerable lateral component. The pile-soil response to lateral loads can be described with the p-y method. For a given depth the load–deflection relationship is built to simulate the surrounding soil stiffness. This state-of-art paper presents a brief discussion of determination methods for the p-y curves using a standard approach based on the soil parameters derived from laboratory and in-situ tests or directly from field tests. The basic relationships for both cohesive and cohesionless soils are discussed. The advantage of direct design methods to describe the p-y curve relies in the reduction of necessary laboratory tests.

Nonlinear Analysis of Settlement for Cohesionless Soil Foundations Based on In Situ Tests

2012 ◽  
Vol 204-208 ◽  
pp. 107-114
Author(s):  
Ren Ping Li ◽  
Jie Liu
Keyword(s):  
Limit State ◽  
Standard Penetration Test ◽  
Summation Method ◽  
Tangent Modulus ◽  
Cohesionless Soil ◽  
Soil Parameters ◽  
Ultimate Limit State ◽  
In Situ Tests ◽  
Loading Test

A new technique is proposed to calculate nonlinear settlement for foundation by using the data of plate loading test (PLT) and standard penetration test (SPT) or other in-situ tests. Firstly, hyperbolic curve is fitted out from the data of PLT and the tangent modulus equation of soil is established, then correctional tangent modulus (CTM) equation is established by feedback adjusting according to the fitting curve of PLT; Secondly, the CTM equations of different stratified soil at different depth are determined by soil parameters of SPT or other in-situ tests according to linear correlation; Finally, the nonlinear settlement of foundation is calculated by the layerwise summation method. An engineering application of settlement prediction for the largest oil tank in China indicated that this technique is able to calculate the entire nonlinear settlement from initiation to ultimate limit state and obtain accurate results, and it is suitable for cohesionless soil with high permeability.

Analysis of self-boring pressuremeter (SBPM) and Marchetti dilatometer (DMT) tests in granite saprolites

2000 ◽  
Vol 37 (4) ◽  
pp. 796-810 ◽  
Author(s):  
F Schnaid ◽  
J AR Ortigao ◽  
F M Mántaras ◽  
R P Cunha ◽  
I MacGregor
Keyword(s):  
Site Investigation ◽  
Friction Angle ◽  
Soil Parameters ◽  
Residual Soil ◽  
Residual Soils ◽  
In Situ Tests ◽  
Cemented Sand ◽  
Fundamental Parameters ◽  
Analysis Technique

This paper presents the analyses of the results of the site investigation programme carried out at the Kowloon Bay site in Hong Kong. The tests consisted of self-boring pressuremeter (SBPM), Marchetti dilatometer (DMT), and laboratory tests carried out in a granite saprolite, which can be described as a lightly cemented sand. The purpose of this research project is to stimulate the development of methods to interpret data obtained from tests in residual soils. In particular, the work aims to evaluate the analyses of the SBPM data through a curve-fitting technique. Both the loading and unloading portions of the SBPM curve were analysed and the results compared with those from other tests. The advantage of this analysis technique is the possibility of constructing a theoretical curve that reproduces a pressuremeter test from which a set of fundamental parameters can be derived, namely the friction angle, cohesion intercept, lateral stress, and shear modulus. The DMT proved to be a reliable tool that yielded good soil parameters at a small fraction of the cost of the other in situ tests.Key words: residual soil, in situ tests, pressuremeter, Marchetti dilatometer.

Determination of horizontal geostatic stress in clay with self-bored pressuremeter

1988 ◽  
Vol 25 (3) ◽  
pp. 559-573 ◽  
Author(s):  
M. G. Jefferies
Keyword(s):  
Key Words ◽  
Image Matching ◽  
The Self ◽  
In Situ Tests ◽  
Extended Theory ◽  
Computer Aided ◽  
Modelling Procedure

The Gibson–Anderson theory for interpretation of pressuremeter data in clay is extended to include the unloading part of the test for the particular circumstances that prevail with a self-bored pressuremeter (SBP). Incorporation of the extended theory in a computer-aided modelling procedure allows horizontal geostatic stress to be unambiguously determined from SBP data by image matching irrespective of imperfections in the self-boring process. The procedure is illustrated by example on a previously reported test carried out in Beaufort Shelf clay. Key words: clay, in situ tests, self-bored pressuremeter, K0.

scholarly journals 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 ]

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.

scholarly journals The analysis on the correlation parameters of the embankment compaction under in situ conditions

2013 ◽  
Vol 12 (3) ◽  
pp. 097-104
Author(s):  
Maciej Kumor ◽  
Łukasz Kumor ◽  
Joanna Farmas
Keyword(s):  
Particle Size ◽  
In Situ Tests ◽  
Geotechnical Assessment ◽  
In Situ Conditions ◽  
Wide Range ◽  
Correlation Parameters ◽  
And Control

Geotechnical assessment of the implementation correctness of a road embankment wide range of issues, among which important selection and control of the quality of the earthworks are extremely significant. The article presents results of in situ tests determining correlations between the depending parameters defined by a static plate – VSS test – E1 and E2, and obtained from the study LFG Dynamic Load Plate. Studies indicate that the determination of the correlation between the parameters characterizing the particle size distribution (Cc, Cu, D10, D20, D30, D60), and the compaction parameters obtained by examining the compaction of sand embankment (Evd, E1, E2, I0) is physically complex and hence extremely difficult. 

scholarly journals Improvement of Gas Drainage Efficiency via Optimization of Sealing Depth of Cross-Measure Boreholes

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Pu Li ◽  
Zhiheng Cheng ◽  
Liang Chen ◽  
Hongbing Wang ◽  
Jialin Cao
Keyword(s):  
Stress Concentration ◽  
Drainage System ◽  
Stress Concentration Zone ◽  
Concentration Zone ◽  
Air Leakage ◽  
In Situ Tests ◽  
Gas Drainage ◽  
Drainage Borehole

The sealing depth of a gas-drainage borehole is critically important as it directly affects the efficiency of the whole drainage system. In order to determine the shortest reasonable sealing depth, in this paper, a theoretical drainage model using different sealing depths was proposed. Based on theoretical analysis presented, two parts of the fractures system surrounding the drainage borehole were proposed, i.e. the fractures induced by roadway excavation and the fractures induced by borehole drilling. A series of geological in-situ tests and simulations research were conducted to determine the stress and fracture distributions in the surrounding rock of the borehole. The depths of crushing zones, plastic zones and stress concentration zones were determined as 5 m, 2 m and 12 m, respectively. Meanwhile, stress simulation shows that the depth of the stress concentration zone was 12 m from the roadway wall and the stress peak was located at the depth of 8 m, which can be verified by the results of drilling penetration velocity analysis. To determine the optimum sealing depth, gas drainage holes with different sealing depths were drilled in the field. The field results revealed that the crushing zones were the main area for air leakage, and the stress concentration induced by roadway excavation assisted in the reduction of air leakage. Therefore, the optimized sealing depth should both cover the plastic zone and the stress concentration zone. The research achievements can provide a quantitative method for the determination of optimum sealing depth in cross-measure drainage boreholes.

New equipment for densification of granular soils at depth

1990 ◽  
Vol 27 (2) ◽  
pp. 167-176
Author(s):  
R. G. Campanella ◽  
R. Hitchman ◽  
W. E. Hodge
Keyword(s):  
Field Testing ◽  
Independent Study ◽  
Soil Parameters ◽  
Granular Soils ◽  
In Situ Tests ◽  
River Sand ◽  
University Of British Columbia ◽  
A Site ◽  
The Phoenix

An in situ densification probe that employs the novel technique of simultaneous vibration and dewatering has been developed by Phoenix Engineering Ltd. to compact deep, loose, granular soils. It is believed that pumping water out of the soil during the densification process offers improved densification capability over systems operating with vibration alone. An independent study was undertaken by the In-Situ Testing Group at the University of British Columbia to evaluate the performance of the Phoenix system.A field testing programme was conducted at a site in Vancouver where hydraulic sand fill overlies a natural silt and then medium Fraser River sand. Characterization of the site and evaluation of the densification treatment process were achieved using in situ tests. Changes to soil parameters due to densification treatment were examined, taking into account the modification of stresses brought about by the vibro-drainage process. The study investigated the degree of densification achieved, the value of concurrent drainage, the zone of influence of a single compaction probe, and group effects. The study also compares the performance of the Phoenix machine with that of other vibrocompaction equipment. Key words: in situ, densification, soils, granular, probe, vibratory, drainage, compaction, R&D.

Sign in / Sign up

Export Citation Format

Share Document