Elastic-Plastic analysis

Fisher, S. and Marom, G. (1984). A complete elastic-plastic analysis of Aramid fiber composites. Composites Sci. Technol. 20, 91-98. 

Arnold, S.M., Arya, V.K. and Melis, M.E. (1990). Elastic/plastic analysis of advanced composite investigating the use of the compliant layer concept in reducing residual stresses resulting from processing, NASA TM-103204. 

The residual stress effect is considered by the separate analysis model and unified analysis model, and the results are shown in figures 3(a) and (b). Figure 3(a) corresponds to the elastic analysis and it is seen that the separate analysis model and unified analysis model give the same resultant stress Figure 3(b) corresponds to the eltistic-plastic analysis tmd it is seen that the resultant stresses found from the two models are different. This is because in the elastic analysis the two responses in phase I and phase II are both linear and the resultant response can be obtained from a direct superposition of the two separate ones. In the elastic-plastic analysis, however, the two separate responses are both nonlinear and the separate analysis model based on the direct superposition of the two separate responses is no longer suitable. 

In the elastic-plastic analysis, the separate ancilysis model and the unified analysis model give the different results because the two responses of the cooling and working phases are both nonlinear. In this case, the separate analysis model is no longer suitable and the unified analysis model should be used.. 

According to Landes and Wei [2], the connection between the steady-state creep rate and the crack-driving force (characterized by K) is derived through the use stress-strain results from elastic-plastic analysis by Hutchinson [9] and Rice and Rosengren [10], According to these models, crack-tip stress and strains in the loading direction (y-direction) are given by Eqn. (6.7). 

There has been the question why the TPV materials with ductile thermoplastic matrix display rubber elasticity. Several models have been suggested to answer this question (41 7). Inoue group first analyzed the origin of mbber elasticity in TPVs (43). They constructed a two-dimensional model with four EPDM mbber inclusions in ductile PP matrix and carried out the elastic-plastic analysis on the deformation mechanism of the two-phase system by finite-element method (FEM). The FEM analysis revealed that, even at highly deformed states at which almost the whole matrix has been yielded by the stress concentration, the ligament matrix between mbber inclusions in the stretching direction is locally preserved within an elastic limit and it acts as an in-situ formed adhesive for interconnecting mbber particles. 

Kikuchi, Y., Fukui, T., Okada, T. and Inoue, T. (1991) Elastic-plastic analysis of the deformation mechanism of PP-EPDM thermoplastic elastomer Origin of rubber elasticity. Polymer Engng Sci., 31, 1029-1032. 

Finite element analysis is useful for elastic or elastic-plastic analysis of single-lap joints. It can also be applied to other joint geometries such as double-lap and modified-lap types. 

In cases where Oa- is greater than 3S but less than 3m5m, die rules of the ASME Code, VIII, paragraph 4-136.4, apply for a simplified elastic-plastic analysis. In this case... 

In this division, there is the possibility to estimate the results of an FE analysis based on the KD-230 Elastic-plastic analysis and KD-240 Linear elastic analysis. KD-3 Fatigue evaluation and KD-4 Fracture mechanics evaluation also give a guideline to assess the protection against failure from cyclic loading. 

The minimum required thickness can be determined by using closed-form equations for cylindrical and spherical shells, blind ends, threaded closures, and clamp connections. The elastic-plastic analysis can be used in most cases and for all D/d ratios. The linear elastic analysis is permitted only if D/d< 1.25 [17]. 

Kavanagh, G. M., Tod, D. A. (2002). Elastic-plastic analysis of bonded joints in rocket motor structures. Extended Abstracts to Euradh /Adhesion 02, lOM Communications,... 

The important aspect to consider is that the corresponding strain amplimde and life N are both the real ones, the first was imposed to the specimen under testing, the second measured. Therefore, with this procedure it is sufficient to calculate stresses in the linear elastic regime as if the material were ideally perfect elastic and enter the ideally elastic S-N curve of the material to derive the allowable fife N. Stress values are not truth, but the corresponding strains are. The procedure needs no sophisticated elastic plastic analysis If we compare the two... 

An important step in local strain fatigue analysis under irregular variation of load with time, as schematized in Fig. 6.16a, is the knowledge of the local notch strain-stress history, as shown in Fig. 6.16c. This, in turn, necessitates the knowledge of the cyclic stress-strain characteristic of the material (see Sect. 1.3.1). Advanced elastic-plastic analysis technique such as finite element computer code is needed or it can be used a simplified Neuber s rule as described in the next section. 

Wilson, W.K. Elastic-plastic analysis of blunt notched ct specimens and applications. J. Press. Vessel Technol. 96(4), 293-298 (1974)... 

Considering the out-of-plane tranverse tensile stresses, crn, in the case of the single lap joint, then obviously, from the above comments, they are most significant and cannot be ignored. Therefore, to accompany his elastic-plastic analysis of the shear stresses Hart-Smith [66] derived solutions for these transverse stresses, but he assumed only elastic behaviour of the adhesive since this was considered to model the adhesive behaviour in tension sufficiently accurately (see Fig. 6.3). For a single lap joint with identical substrates, the maximum value, crii(max), in the adhesive at the ends of the overlap is given by ... 

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