scholarly journals Study of the bearing capacity and settlement behavior of skirted foundations resting on cohesive soils

2020 ◽  
Vol 16 (32) ◽  
pp. 35-45
Author(s):  
Sajjad Gholipour ◽  
Masoud Makarchian ◽  
Reza Gholipour ◽  
◽  
◽  
...  
Keyword(s):  
Bearing Capacity ◽  
Cohesive Soils ◽  
Settlement Behavior

scholarly journals Simulation Study of the Load-settlement Behavior of a Single Pile Using the Osterberg-cell Test Based on the Load Transfer Theory

2016 ◽  
Vol 10 (1) ◽  
pp. 813-825
Author(s):  
Lina Xu ◽  
Xuedong Guo ◽  
Lei Nie ◽  
Yongmei Qian
Keyword(s):  
Bearing Capacity ◽  
Load Transfer ◽  
Simulation Analysis ◽  
Deformation Analysis ◽  
Single Pile ◽  
Simulation Test ◽  
Transfer Theory ◽  
Settlement Behavior ◽  
Cell Test ◽  
Selection Of

In this paper, a theoretical relationship between the load and settlement of a single pile in an Osterberg-Cell test was developed, considering the joint action of piles and soil and a detailed deformation analysis was conducted based on the load transfer theory of piles. The shear test and the compression test were used to determine the load transfer parameters for soil layers around a pile at various depths as well as the parameters for pile-tip soils. Based on this method, a simulation analysis program was applied to determine the location of the balance point in the Osterberg-Cell test to provide a reference for the test design. The analytical methods presented in this paper could be considered practical because the results from the simulation test and on-site measurement indicate that the theoretically predicted result is consistent with the measurements. A reasonable selection of the location of the hydraulic jack-like device (O-cell) could maximize the bearing capacity of testing piles to obtain a more accurate ultimate bearing capacity. This study provides a reference for the design of the Osterberg-Cell test as well as pile foundations.

scholarly journals A Framework to Predict the Load-Settlement Behavior of Shallow Foundations in a Range of Soils from Silty Clays to Sands using CPT Records

2021 ◽  
Author(s):  
Hossein MolaAbasi ◽  
Aghileh Khajeh ◽  
REZA JAMSHIDI CHENARI ◽  
Meghdad Payan
Keyword(s):  
Bearing Capacity ◽  
Volterra Series ◽  
Current Model ◽  
Shallow Foundations ◽  
Hyperbolic Function ◽  
Cone Penetration ◽  
Settlement Behavior ◽  
Tip Resistance ◽  
Allowable Bearing Capacity ◽  
Load Tests

Abstract Using a set of cone penetration test (CPT) records,the current paper develops a general framework based on regression analyses to model the load-settlement (q-s) behavior of shallow foundations resting on a variety of soils ranging from silty clays to sands.A three-parameter hyperbolic function is employed to rigorously examine the obtainedq-s curves, and to determine the model parameters.Also, the results of someCPT soundings, including the corrected cone tip resistance (qt) and the skin friction (Rf),are adopted to predict the results of plate load tests(PLT). The findingscorroborate the high accuracy of the proposed model, thereasonable performance of the hyperbolic function and the use of the Volterra series to predict the q-s curves.Moreover, the obtained curves from the newly developed model arecompared to those from other methods in the literature which cross-confirms the efficacyof the current model. Asensitivity analysis isalso conductedand the exclusive effects of all the contributing parameters are assessed among which Rfis shown to be the most influential. Ultimately, simple solutionsare adoptedto determine variouskey geotechnical parameters, like the ultimate bearing capacity (qult), the allowable bearing capacity (qa) andthe modulus of subgrade reaction (ks).

scholarly journals Influence of time on the bearing capacity of precast piles

2013 ◽  
Vol 35 (4) ◽  
pp. 65-74 ◽  
Author(s):  
Kazimierz Gwizdała ◽  
Paweł Więcławski
Keyword(s):  
Bearing Capacity ◽  
Cohesive Soils ◽  
Geotechnical Parameters ◽  
Well Control ◽  
Time Points ◽  
Pile Shaft ◽  
Field Investigations ◽  
Load Tests ◽  
Pile Load Tests ◽  
Change Of Microstructure

Abstract One of the most popular types of foundations in layered subsoil with very differentiated soil shear strengths are precast piles. One of the reasons is the fact that we can well control the driving process during the installation of these piles. The principles of the assessment of bearing capacity and settlements of the piles given by Eurocode 7, concentrate on two main methods, i.e., Static Pile Load Tests (SPLT) and Dynamic Driving Analysis (PDA). However, the evaluation of real load-settlement curve for piles being driven in layered subsoil, where noncohesive and cohesive soils occur alternately, is neither easy nor straightforward. In the paper, the results of both SPLT and PDA tests for objects on the highways in Poland are presented. Field investigations carried out at various time points since the installation of piles (from 7 to 90 days) revealed an increase of bearing capacity with time. The reason for this may be a change of the soil state near the piles due to their driving (displacement of piles) as well as a change of microstructure at the contact between soil and pile shaft. The results of load tests were referred to the geotechnical parameters of the subsoil, which was recognized by means of traditional borings and CPTU tests. The results of tests allow phenomena occurring with time to be assessed and bearing capacity of precast piles to be predicted.

scholarly journals A Review Study on Sand Compaction Piles in Cohesive Soils and as a Liquefaction Resistance Technique

2020 ◽  
pp. 354-357
Author(s):  
Aarthi N
Keyword(s):  
Bearing Capacity ◽  
State Of The Art ◽  
Ground Improvement ◽  
The State ◽  
Cohesive Soils ◽  
Liquefaction Resistance ◽  
Detailed Review ◽  
The Subject ◽  
Review Study

The paper presents a detailed review of the state-of-the-art ground improvement technique namely sand compaction piles. The technique being originated in Japan has flourished around the globe for its efficient characteristics to act as a reinforcing member when it is installed in clays and is recognized as one of the best methods to prevent liquefaction. Known for its larger bandwidth of advantages, articles summarising the literature contribution on the technique are found to be very limited. Therefore, an attempt has been made to review the noteworthy literature that provides valuable information on the subject. An overview of the literature present on sand compaction piles installed in cohesive soils targeted to meet various demands like increasing bearing capacity, settlement, etc., and the technique’s efficiency in mitigating liquefaction associated problems are discussed.

scholarly journals The Behavior of Strip Footing Resting on Soil Strengthened with Geogrid

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Duaa Al-Jeznawi ◽  
Adel A. Al-Azzawi
Keyword(s):  
Finite Elements ◽  
Bearing Capacity ◽  
Soil Improvement ◽  
Strip Footing ◽  
Analytical Models ◽  
Number Of Layers ◽  
Settlement Behavior ◽  
Load Carrying ◽  
Low Load ◽  
The World

Abstract The soil in Iraq has a low load carrying or bearing capacity and high deflections or settlement because of the applied loads. The use of strip footing as a foundation to support different kinds of heavy structures has become necessary nowadays through solving such problems by using geogrid. This soil improvement technique is widely used all over the world. In this paper, the bearing capacity and settlements were calculated using finite elements and analytical models for strip footing resting on different kinds of soil. The study parameters are footing rigidity, the number of layers in a geogrid, the dimension of geogrid, and spacing of geogrid layers. According to the findings, the geogrid improved the bearing ability of the footing and reduced settlement. The optimum geogrid dimension was three times the footing width, and three geogrid layers were optimum. The changing in footing rigidity also affects the stress and settlement behavior.

Capacité portante de pieux isolés dans les argiles sensibles: étude de cas par la méthode pénétrométrique

1989 ◽  
Vol 26 (3) ◽  
pp. 375-384 ◽  
Author(s):  
Marius Roy ◽  
Luc Tanguay
Keyword(s):  
Bearing Capacity ◽  
Key Words ◽  
Cohesive Soils ◽  
Friction Component ◽  
Good Potential ◽  
Capacité Portante ◽  
Loading Tests ◽  
Single Piles ◽  
Lateral Friction

The penetrometer test has been used to determine the bearing capacity of driven and jacked-in single piles in sensitive clays. The cases presented in this paper were carried out on two sites with steel, concrete, and wooden piles. The bearing capacities calculated on the basis of the results of penetrometer tests show that this approach has a good potential and at the same time is simple and fast. It has been possible to obtain a calibration by a comparison with the loading tests carried out on each of the piles. Taking into account the low strength of some of our clays, experience has to be gained in order to adapt the lateral unit friction curves to our clays. This approach also has the advantage of allowing the determination of the bearing capacity of wooden piles and of taking into account the conical effect when determining the lateral friction component. Key words: penetrometer test, piles, bearing capacity, cohesive soils, point resistance, lateral friction, steel, concrete, wood. [Journal translation]

scholarly journals Proposal for calculating the bearing capacity of screw displacement piles in non-cohesive soils based on CPT results

2012 ◽  
Vol 34 (4) ◽  
pp. 41-51 ◽  
Author(s):  
Adam Krasiński
Keyword(s):  
Bearing Capacity ◽  
Static Loading ◽  
Load Transfer ◽  
Transfer Functions ◽  
Cohesive Soil ◽  
Cohesive Soils ◽  
Considerable Influence ◽  
Calculation Methods ◽  
Capacity Calculation ◽  
Loading Tests

Abstract Screw displacement pile technology is relatively new and is still being developed. A specific characteristic of those piles is their very considerable influence on soil properties during the installation, which renders classical bearing capacity calculation methods insufficient. Some methods for calculating the bearing capacity of screw displacement piles have already been presented in literature, for example, by Bustmante and Gianesselli [2], [3], Van Impe [17], [18], Maertens and Huybrechts [15], Ne Smith [16] as well as Basu and Prezzi [1]. This paper proposes a new method of calculating the bearing capacity of screw displacement piles in non-cohesive soil which is based on CPT results. It has been devised as a result of research project No. N N506 432936 [11], carried out in 2009-2011. At 6 experimental sites screw displacement pile static loading tests were carried out together with CPTU tests of the subsoil. The results allowed us to establish soil resistances along the shaft ts as well as under the pile base qb and their correlations to the CPT soil cone resistances qc. Two approaches, both adapted to the general guidelines of Eurocode 7 (EC7) [20], were proposed: a classical approach and the second approach with load transfer functions application.

scholarly journals Comparison of shallow foundation design using Eurocode 7 and Polish Standard

2014 ◽  
Vol 20 (1) ◽  
pp. 57-62 ◽  
Author(s):  
Andrzej Olchawa ◽  
Andrzej Zawalski
Keyword(s):  
Bearing Capacity ◽  
Friction Angle ◽  
Cohesive Soil ◽  
Shallow Foundation ◽  
Cohesive Soils ◽  
Foundation Design ◽  
Eurocode 7 ◽  
Liquidity Index ◽  
Undrained Conditions ◽  
Factor Α

Abstract Bearing capacity of cohesive soils was calculated based on PN-B-03020:1981P and Eurocode 7. Strength parameters of cohesive soil modified by the authors: shear strength in undrained conditions cu, effective cohesion c' and effective friction angle φ' were adopted for calculations acc. to Eurocode 7. Values of these parameters depend on a leading parameter - liquidity index IL. Bearing capacity was calculated for two pad foundations of a size B × L = 2.0 × 3.0 m and 1.5 × 2.0 m and for one 2.0 × 14.0 m strip foundation. The capacity calculated acc. to EC 7 was reduced by multiplying by a factor α = 0.87 to account for different bearing capacity coefficients in Polish Norms and Eurocodes. Performed calculations showed comparable bearing capacity of substratum irrespective of adopted norms EC 7 and PN for foundation pads. In all analysed cases, however, the bearing capacity of foundation strips calculated acc. to Eurocode 7 was higher than those calculated acc. to PN-B-03020:1981P. The reason is in the values and ways of accounting partial security coefficients and in differences in the values of shape coefficients used in the equation for ultimate bearing resistance of soil substratum.

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