CAJ | 학술논문

基于CLoE与Gudehus-Bauer亚塑性模型数值模拟了平面应变条件下Hostun砂的应变局部化现象。从侧向压力和初始缺陷两个方面对比研究了两种模型所预测应变局部化的产生及演化模式。结果表明：（1）两种模型均能反映 Hostun 砂刚度随着侧向压力提高而增大的现象。（2）相比Gudehus-Bauer亚塑性模型，CLoE亚塑性模型所得出的应变局部化形态与试验结果更加一致。（3）CLoE 亚塑性模型能够反映随着荷载增加，砂的体积先膨胀后缩小的特点。（4）相比 Gudehus-Bauer亚塑性模型，CLoE亚塑性模型所得到的应变-应力曲线能够更明显地反映应变局部化带中单元的软化现象。（5）CLoE亚塑性模型能够更好地模拟由初始缺陷导致的不均匀应变。总的来说，所得的数值结果表明，CLoE亚塑性模型能够较好地模拟侧向压力和初始缺陷对应变局部化的影响，在模拟应变局部化现象方面较Gudehus-Bauer更有优势。然而，现有CLoE亚塑性模型无法考虑孔隙比，也未包含颗粒材料内尺度变量，有待进一步完善。
기우CLoE여Gudehus-Bauer아소성모형수치모의료평면응변조건하Hostun사적응변국부화현상。종측향압력화초시결함량개방면대비연구료량충모형소예측응변국부화적산생급연화모식。결과표명：（1）량충모형균능반영 Hostun 사강도수착측향압력제고이증대적현상。（2）상비Gudehus-Bauer아소성모형，CLoE아소성모형소득출적응변국부화형태여시험결과경가일치。（3）CLoE 아소성모형능구반영수착하재증가，사적체적선팽창후축소적특점。（4）상비 Gudehus-Bauer아소성모형，CLoE아소성모형소득도적응변-응력곡선능구경명현지반영응변국부화대중단원적연화현상。（5）CLoE아소성모형능구경호지모의유초시결함도치적불균균응변。총적래설，소득적수치결과표명，CLoE아소성모형능구교호지모의측향압력화초시결함대응변국부화적영향，재모의응변국부화현상방면교Gudehus-Bauer경유우세。연이，현유CLoE아소성모형무법고필공극비，야미포함과립재료내척도변량，유대진일보완선。
To compare CLoE and Gudehus-Bauer hypoplastic models, a series of finite element analyses were carried out on modeling the strain localization for Hostun sand under plane strain condition. The strain localization was analyzed mainly in terms of different confining pressures and same initial imperfection. The results are drawn as follows. (1) Compressive hardening can be observed by two hypoplastic models;the stiffness of Hostun sand rises with the increasing of confining pressures. (2) The pattern of strain localization from the results of CLoE hypoplastic model is more compatible with the results of experiments than Gudehus-Bauer model. (3) CLoE hypoplastic model can simulate volume expansion before shrink with the increase of load of Hostun sand. (4) The softening behavior under high confining pressures of the elements in strain localization is more obvious in the strain-stress curve based on CLoE hypoplastic model. (5) CLoE hypoplastic model is better than Gudehus-Bauer model in simulating the nonuniform strain localization which is caused by initial imperfection. All in all, numerical results suggest that CLoE model performs better than Gudehus-Bauer model in modeling strain localization. What’s more, influences of confining pressure and initial imperfection can be modeled by CLoE hypoplastic model. However, CLoE model should be improved because of void ratio and intrinsic length scales unconsidered.