Plane-strain investigation of rubber specimens using a variable Poisson's ratio

1972 ◽  
Vol 5 (2) ◽  
pp. 284-285
Author(s):  
B. M. Gorelik ◽  
M. A. Maiskaya ◽  
V. G. Loginov ◽  
G. I. Fel'dman
Keyword(s):  
Plane Strain ◽  
Poisson’S Ratio ◽  
Poisson's Ratio

Settlement of a strip footing on a confined clay layer

1983 ◽  
Vol 20 (3) ◽  
pp. 535-542
Author(s):  
Brian B. Taylor ◽  
Elmer L. Matyas
Keyword(s):  
Stress Distribution ◽  
Plane Strain ◽  
Poisson’S Ratio ◽  
Ground Surface ◽  
Finite Depth ◽  
Strip Footing ◽  
Poisson's Ratio ◽  
Clay Layer ◽  
Line Load ◽  
Settlement Analysis

A procedure is described that permits an estimation of either consolidation or immediate settlements of a uniformly loaded, flexible strip footing founded below the ground surface. The soil above the base of the footing is sand, and the soil below the base consists of clay, which extends to a finite depth. The procedure is based on a solution of Kelvin's equations for a line load acting within an infinite solid. Charts are presented which permit an estimate of settlement for various compression moduli, Poisson's ratio, and clay thickness.The proposed method predicts consolidation settlements that are generally slightly greater than those predicted from Boussinesq theory. Consolidation settlements increase as Poisson's ratio increases. Immediate settlements are slightly greater than those reported previously. Keywords: consolidation, elasticity, footings, plane strain, settlement analysis, stress distribution.

Response of a Viscoelastic Annulus to a Step Transverse Load

1970 ◽  
Vol 92 (3) ◽  
pp. 425-434
Author(s):  
S. R. Robertson
Keyword(s):  
Plane Strain ◽  
Poisson’S Ratio ◽  
Logarithmic Decrement ◽  
Poisson's Ratio ◽  
Transverse Load ◽  
Transverse Loads ◽  
Work Done

The problem of finding the response of a viscoelastic annulus in plane strain to step, transverse loads is solved. It is solved by employing Valanis’ method which assumes constant Poisson’s ratio. The resulting displacements are used to calculate the work done by the applied transverse load for various thicknesses of the annuli. A simple spring-dashpot model is then fitted to the work versus time curves so as to provide the logarithmic decrement for design.

Parameters governing load trasnfer for single reinforcing members

1973 ◽  
Vol 8 (1) ◽  
pp. 35-42
Author(s):  
N C Remedios ◽  
W G Wood
Keyword(s):  
Aspect Ratio ◽  
Plane Strain ◽  
Plane Stress ◽  
Poisson’S Ratio ◽  
Stress Transfer ◽  
Quantitative Comparison ◽  
Poisson's Ratio ◽  
Stiffness Parameter ◽  
Stress Diffusion ◽  
Matrix Modulus

The diffusion of stress between a single reinforcing member and a matrix is shown to be a function of three main parameters. These are: position along the stiffener; a stiffness parameter which is the product of the ratio of stiffener to matrix modulus and the aspect ratio of the stiffener; a matrix-width parameter. The effects of variations in Poisson's ratio are found to be small so that similar patterns of stress transfer occur in plane-stress and plane-strain systems if the governing parameters for the systems are the same. No quantitative comparison can be made between stress diffusion in plane and axisymmetric systems.

scholarly journals Bond-based peridynamics: A tale of two Poisson's ratios

2019 ◽  
Author(s):  
Jeremy Trageser ◽  
Pablo Seleson
Keyword(s):  
Plane Strain ◽  
Plane Stress ◽  
Poisson’S Ratio ◽  
Poisson's Ratio ◽  
Two Dimensional ◽  
Isotropic Materials ◽  
Stress Models ◽  
Poisson's Ratios ◽  
Poisson’S Ratios

This paper explores the restrictions imposed by bond-based peridynamics, particularly with respect to plane strain and plane stress models. We begin with a review of the derivations in [2] wherein for isotropic materials a Poisson's ratio restriction of 1/4 for plane strain and 1/3 for plane stress is deduced. Next, we show Cauchy's relations are an intrinsic limitation of bond-based peridynamics and specialize this result to plane strain and plane stress models, generalizing the results of [2] and demonstrating the Poisson's ratio restrictions in [2] are simply a consequence of Cauchy's relations. We conclude with a discussion of the validity of peridynamic plane strain and plane stress models formulated from two-dimensional bond-based peridynamic models.

The Model for Calculating Elastic Modulus and Poisson's Ratio of Coal Body

2013 ◽  
Vol 6 (1) ◽  
pp. 36-43 ◽  
Author(s):  
Ai Chi ◽  
Li Yuwei
Keyword(s):  
Elastic Modulus ◽  
Poisson’S Ratio ◽  
Fractured Rock ◽  
Rock Block ◽  
Poisson's Ratio ◽  
Linear Elastic ◽  
Study Results ◽  
The Face ◽  
Block Face ◽  
Coal Rock

Coal body is a type of fractured rock mass in which lots of cleat fractures developed. Its mechanical properties vary with the parametric variation of coal rock block, face cleat and butt cleat. Based on the linear elastic theory and displacement equivalent principle and simplifying the face cleat and butt cleat as multi-bank penetrating and intermittent cracks, the model was established to calculate the elastic modulus and Poisson's ratio of coal body combined with cleat. By analyzing the model, it also obtained the influence of the parameter variation of coal rock block, face cleat and butt cleat on the elastic modulus and Poisson's ratio of the coal body. Study results showed that the connectivity rate of butt cleat and the distance between face cleats had a weak influence on elastic modulus of coal body. When the inclination of face cleat was 90°, the elastic modulus of coal body reached the maximal value and it equaled to the elastic modulus of coal rock block. When the inclination of face cleat was 0°, the elastic modulus of coal body was exclusively dependent on the elastic modulus of coal rock block, the normal stiffness of face cleat and the distance between them. When the distance between butt cleats or the connectivity rate of butt cleat was fixed, the Poisson's ratio of the coal body initially increased and then decreased with increasing of the face cleat inclination.

scholarly journals A Hybrid Artificial Intelligence Model to Predict the Elastic Behavior of Sandstone Rocks

2019 ◽  
Vol 11 (19) ◽  
pp. 5283 ◽  
Author(s):  
Gowida ◽  
Moussa ◽  
Elkatatny ◽  
Ali
Keyword(s):  
Poisson’S Ratio ◽  
Accurate Determination ◽  
Oil And Gas Industry ◽  
Poisson's Ratio ◽  
Elastic Behavior ◽  
Percentage Error ◽  
Ann Model ◽  
Field Development ◽  
Well Completion

Rock mechanical properties play a key role in the optimization process of engineering practices in the oil and gas industry so that better field development decisions can be made. Estimation of these properties is central in well placement, drilling programs, and well completion design. The elastic behavior of rocks can be studied by determining two main parameters: Young’s modulus and Poisson’s ratio. Accurate determination of the Poisson’s ratio helps to estimate the in-situ horizontal stresses and in turn, avoid many critical problems which interrupt drilling operations, such as pipe sticking and wellbore instability issues. Accurate Poisson’s ratio values can be experimentally determined using retrieved core samples under simulated in-situ downhole conditions. However, this technique is time-consuming and economically ineffective, requiring the development of a more effective technique. This study has developed a new generalized model to estimate static Poisson’s ratio values of sandstone rocks using a supervised artificial neural network (ANN). The developed ANN model uses well log data such as bulk density and sonic log as the input parameters to target static Poisson’s ratio values as outputs. Subsequently, the developed ANN model was transformed into a more practical and easier to use white-box mode using an ANN-based empirical equation. Core data (692 data points) and their corresponding petrophysical data were used to train and test the ANN model. The self-adaptive differential evolution (SADE) algorithm was used to fine-tune the parameters of the ANN model to obtain the most accurate results in terms of the highest correlation coefficient (R) and the lowest mean absolute percentage error (MAPE). The results obtained from the optimized ANN model show an excellent agreement with the laboratory measured static Poisson’s ratio, confirming the high accuracy of the developed model. A comparison of the developed ANN-based empirical correlation with the previously developed approaches demonstrates the superiority of the developed correlation in predicting static Poisson’s ratio values with the highest R and the lowest MAPE. The developed correlation performs in a manner far superior to other approaches when validated against unseen field data. The developed ANN-based mathematical model can be used as a robust tool to estimate static Poisson’s ratio without the need to run the ANN model.

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