Generalized non-linear strength theory and transformed stress space

Yangping YAO

doi:10.1360/04ye0199

Damage Model for Dissipative Materials with Generalized Non-Linear Strength Theory

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.415-417.1439 ◽

2011 ◽

Vol 415-417 ◽

pp. 1439-1442

Author(s):

Wei Wei Yu ◽

Xuan Guo

Keyword(s):

Internal Structure ◽

Damage Model ◽

Structural Evolution ◽

Strength Theory ◽

Structural Configuration ◽

Progressive Loss ◽

Proposed Model ◽

Non Linear ◽

Predicting Behavior

This paper builds the formulations of damage model for dissipative materials with generalized non-linear strength theory. The proposed model reflects the internal structural configuration and damage behavioure. The structural evolution parameters are introduced to account for the progressive loss of the internal structure. The proposed damage model is proposed by generalized non-linear strength theory, the capability of the models in predicting behavior of clay has been examined.

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Application the Thermomechanical Damage Modeling Approach with Generalized Non-Linear Strength Theory

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.415-417.1417 ◽

2011 ◽

Vol 415-417 ◽

pp. 1417-1420

Author(s):

Xuan Guo ◽

Wei Wei Yu

Keyword(s):

Structural Rearrangement ◽

Internal Variables ◽

Damage Modeling ◽

Strength Theory ◽

Energy Functions ◽

Damage Behavior ◽

Modeling Approach ◽

Non Linear ◽

Thermomechanical Damage ◽

The Given

This paper builds the formulations of thermomechanical damage modeling approach with generalized non-linear strength theory. The bulk and the likely damage behavior can be described. The independent kinematic internal variables are introduced to describe the damage behavior and structural rearrangement of the Geo-granules for bulk deformation. The accordingly generalized stress can be deduced by combining the given thermodynamical energy functions. A systematic constitutive presentation is presented through the thermodynamical damage framework with generalized non-linear strength theory. The theory is based on previous work by Houlsby et al., and extends to the multi-mechanisms (Guo&Zhao et al.) description for geomaterial.

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Experimental Study of Biaxial Load-Unload Behavior of DP590 Steel Sheets

Volume 1: Processing ◽

10.1115/msec2013-1171 ◽

2013 ◽

Author(s):

Yannis P. Korkolis ◽

Nengxiu Deng ◽

Toshihiko Kuwabara

Keyword(s):

Plastic Strain ◽

Yield Function ◽

Elastic Response ◽

Dissipated Energy ◽

Stress Space ◽

Steel Sheets ◽

Anisotropic Yield Function ◽

Biaxial Load ◽

Non Linear ◽

Elastic Unloading

Biaxial load-unload tests under radial paths in the true stress space were carried out for DP590 steel sheets using specially-designed cruciform specimens. Depending on the specific path, over 15% equivalent logarithmic plastic strain was achieved so that the load-unload behavior was successfully probed at relatively high strain levels. It was found that the stress-strain response at the initial load/unload follows the predicted linearly elastic response very well and that subsequently the slope decays. Following this initial phase, a second linear response is observed, which ultimately leads to the non-linear plastic response. The biaxial non-linear strain recovery components εxnl and εynl were measured to be on average approximately 11% of the elastic strains εxe and εye, respectively. At higher strains, this ratio is approximately 25%, indicating the inaccuracy of springback simulations when a linearly elastic unloading response is assumed. For each load-unload cycle, the dissipated energy density tends to increase with the progression of prestrain. The plastic work contours covering the first quadrant of the stress space were successfully constructed and the directions of the plastic strain rates were then calculated. A good agreement with the experimental facts was found by adopting the anisotropic yield function Yld2000-2D.

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Extended Transformed Stress Space for Geomaterials and Its Application

Journal of Engineering Mechanics ◽

10.1061/(asce)0733-9399(2007)133:10(1115) ◽

2007 ◽

Vol 133 (10) ◽

pp. 1115-1123 ◽

Cited By ~ 32

Author(s):

Yang-Ping Yao ◽

An-Nan Zhou ◽

De-Chun Lu

Keyword(s):

Stress Space ◽

Transformed Stress

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B. The Non-Linear Calculations for Pulsating Stars

Symposium - International Astronomical Union ◽

10.1017/s0074180900019008 ◽

1967 ◽

Vol 28 ◽

pp. 105-176

Author(s):

Robert F. Christy

Keyword(s):

Major Part ◽

Afternoon Session ◽

Discussion Session ◽

Pulsating Stars ◽

Fourth Symposium ◽

Non Linear ◽

Considerable Discussion ◽

Informal Approach ◽

Preceding Session

(Ed. note: The custom in these Symposia has been to have a summary-introductory presentation which lasts about 1 to 1.5 hours, during which discussion from the floor is minor and usually directed at technical clarification. The remainder of the session is then devoted to discussion of the whole subject, oriented around the summary-introduction. The preceding session, I-A, at Nice, followed this pattern. Christy suggested that we might experiment in his presentation with a much more informal approach, allowing considerable discussion of the points raised in the summary-introduction during its presentation, with perhaps the entire morning spent in this way, reserving the afternoon session for discussion only. At Varenna, in the Fourth Symposium, several of the summaryintroductory papers presented from the astronomical viewpoint had been so full of concepts unfamiliar to a number of the aerodynamicists-physicists present, that a major part of the following discussion session had been devoted to simply clarifying concepts and then repeating a considerable amount of what had been summarized. So, always looking for alternatives which help to increase the understanding between the different disciplines by introducing clarification of concept as expeditiously as possible, we tried Christy's suggestion. Thus you will find the pattern of the following different from that in session I-A. I am much indebted to Christy for extensive collaboration in editing the resulting combined presentation and discussion. As always, however, I have taken upon myself the responsibility for the final editing, and so all shortcomings are on my head.)

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