An attempt to apply the kinematic method of rigid solids in the study of bearing capacity of shallow foundations

Abstract In the geotechnical engineering field, shallow foundations are frequently needed to ensure good fieldwork stability. They are also intended to permanently and uniformly transmit all load pressure on the seating floor. However, numerous mechanical constraints, such as bearing capacity of foundations, durability, stability, design of shallow foundations, lead, unfortunately, to a serious realization challenge. Finding an adequate solution presents the main goal and effort of both scholars and professionals. Indeed, the corresponding drawback is observed through the high number of reported damages that occurred in the structure of foundations and the punching failure. The failure mechanisms of shallow foundations, verified in full size or on scale models, show “sliding surfaces” and rigid (solid) blocks, which can be described with the kinematic method of rigid solids. The main objective of this study is the application of the kinematic method of rigid solids in the study of the stability of shallow foundations with respect to punching, the purpose of which is to determine the bearing capacity factors Nc, N γ, and the passive earth pressure coefficient Kp of foundations. In this context, two mechanical models have been proposed with 5 and 7 rigid solids, and a program developed via the MathCAD environment is applied to check the validity of the two previous models. The kinematic method of rigid solids gives results very close and comparable with that of Caquot/Kerisel for the factors of the bearing capacity and passive earth pressure coefficient - the ratio Kp - according to the five- and seven-solid model.

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Experimental Study on a Three-Dimensional Passive Earth Pressure Coefficient in Cohesionless Soil

Lecture Notes in Civil Engineering - Geotechnical Research for Land Protection and Development ◽

10.1007/978-3-030-21359-6_58 ◽

2019 ◽

pp. 545-554

Author(s):

P. Capilleri ◽

E. Motta ◽

M. Todaro ◽

G. Biondi

Keyword(s):

Experimental Study ◽

Pressure Coefficient ◽

Three Dimensional ◽

Earth Pressure ◽

Cohesionless Soil ◽

Passive Earth Pressure ◽

Earth Pressure Coefficient

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Use of the ranking distance as an index for assessing the accuracy and precision of equations for the bearing capacity of piles and at-rest earth pressure coefficient

Canadian Geotechnical Journal ◽

10.1139/t03-063 ◽

2003 ◽

Vol 40 (6) ◽

pp. 1200-1207 ◽

Cited By ~ 14

Author(s):

T LL Orr ◽

C Cherubini

Keyword(s):

Bearing Capacity ◽

Pressure Coefficient ◽

Probabilistic Approach ◽

Statistical Parameter ◽

Earth Pressure ◽

Central Tendency ◽

Accuracy And Precision ◽

Bias Factor ◽

Earth Pressure Coefficient ◽

Ranking Distance

In many geotechnical design situations, a number of different calculation models have been developed to predict the value of a particular quantity required for use in design calculations, for example, the bearing capacities of driven and root piles, and K0, the at-rest earth pressure coefficient. In this paper the authors show how the dependability of different calculation methods can be compared and assessed using a synthetic probabilistic approach and the ranking distance (RD) index. Measured values, Qmeas, are compared with calculated values, Qcalc, using the "bias factor," defined as the ratio Qmeas/Qcalc. The bias factor values obtained using a particular calculation method are processed to evaluate the "accuracy" and "precision" by calculating a central tendency and a variability statistical parameter, respectively, from the values. The RD index is a comprehensive statistical parameter for assessing the dependability of a particular calculation method and is based on the central tendency and variability. Using the ratios between calculated and measured bearing capacity and earth pressures values, the RD index is used to assess the accuracy and precision of the most frequently used pile driving formulae, two equations for the bearing capacity of root piles, and seven equations for the at-rest earth pressure coefficient.Key words: accuracy, precision, probabilistic approach, ranking distance.

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Limit equilibrium computation of dynamic passive earth pressure

Canadian Geotechnical Journal ◽

10.1139/t95-050 ◽

1995 ◽

Vol 32 (3) ◽

pp. 481-487 ◽

Cited By ~ 44

Author(s):

Ernest E. Morrison Jr. ◽

Robert M. Ebeling

Keyword(s):

Limit Equilibrium ◽

Pressure Coefficient ◽

Earth Pressure ◽

Failure Surface ◽

Friction Angle ◽

Passive Earth Pressure ◽

Equilibrium Equations ◽

Cohesionless Soils ◽

Earth Pressures ◽

Earth Pressure Coefficient

Few solution techniques exist for the determination of pseudostatic dynamic passive earth pressures for cohesionless soils. The widely accepted Mononobe–Okabe equation can result in the computing of unconservative values if the wall interface friction angle is greater than half the soil internal friction angle. As an alternate solution, equilibrium equations were formulated assuming a log spiral failure surface, and a research computer program was written to calculate the dynamic passive earth pressure coefficient. The primary purpose of this paper is to present a comparison of results obtained using the Mononobe–Okabe equation with those obtained using the log spiral formulation. Key words : pseudostatic, dynamic, passive earth pressure.

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Response to the comment by Burland and Federico on: "Use of the ranking distance as an index for assessing the accuracy and precision of equations for the bearing capacity of piles and at-rest earth pressure coefficient"

Canadian Geotechnical Journal ◽

10.1139/t05-077 ◽

2005 ◽

Vol 42 (6) ◽

pp. 1720-1722

Author(s):

T L.L Orr ◽

C Cherubini

Keyword(s):

Bearing Capacity ◽

Pressure Coefficient ◽

Earth Pressure ◽

Accuracy And Precision ◽

Earth Pressure Coefficient ◽

Ranking Distance

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Comment on "Use of the ranking distance as an index for assessing the accuracy and precision of equations for the bearing capacity of piles and at-rest earth pressure coefficient"

Canadian Geotechnical Journal ◽

10.1139/t05-076 ◽

2005 ◽

Vol 42 (6) ◽

pp. 1718-1719

Author(s):

J B Burland ◽

A Federico

Keyword(s):

Bearing Capacity ◽

Pressure Coefficient ◽

Earth Pressure ◽

Accuracy And Precision ◽

Earth Pressure Coefficient ◽

Ranking Distance

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Lateral Earth Pressure Coefficient of Soils Subjected to Freeze–Thaw

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.4038032 ◽

2017 ◽

Vol 140 (2) ◽

Cited By ~ 2

Author(s):

Xiaodong Zhao ◽

Guoqing Zhou ◽

Bo Wang ◽

Wei Jiao ◽

Jing Yu

Keyword(s):

Pressure Coefficient ◽

Earth Pressure ◽

Retaining Walls ◽

Saturated Soil ◽

Frozen Soils ◽

Freeze Thaw ◽

Lateral Earth Pressure ◽

Soil Deposits ◽

Earth Pressure Coefficient ◽

Water Saturated

Artificial frozen soils (AFS) have been used widely as temporary retaining walls in strata with soft and water-saturated soil deposits. After excavations, frozen soils thaw, and the lateral earth pressure penetrates through the soils subjected to freeze–thaw, and acts on man-made facilities. Therefore, it is important to investigate the lateral pressure (coefficient) responses of soils subjected to freeze–thaw to perform structure calculations and stability assessments of man-made facilities. A cubical testing apparatus was developed, and tests were performed on susceptible soils under conditions of freezing to a stable thermal gradient and then thawing with a uniform temperature (Fnonuni–Tuni). The experimental results indicated a lack of notable anisotropy for the maximum lateral preconsolidated pressures induced by the specimen’s compaction and freeze–thaw. However, the freeze–thaw led to a decrement of lateral earth pressure coefficient K0, and K0 decrement under the horizontal Fnonuni–Tuni was greater than that under the vertical Fnonuni–Tuni. The measured K0 for normally consolidated and over-consolidated soil specimens exhibited anisotropic characteristics under the vertical Fnonuni–Tuni and horizontal Fnonuni–Tuni treatments. The anisotropies of K0 under the horizontal Fnonuni–Tuni were greater than that under the vertical Fnonuni–Tuni, and the anisotropies were more noticeable in the unloading path than that in the loading path. These observations have potential significances to the economical and practical design of permanent retaining walls in soft and water-saturated soil deposits.

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