| 孔隙分布分形维对多孔材料抗压强度的影响研究 |
| |
| 引用本文： | 鲁功达,晏鄂川,王雪明,谢良甫,高连通.孔隙分布分形维对多孔材料抗压强度的影响研究[J].岩土力学,2014,35(8):2261-2268. |
| |
| 作者姓名： | 鲁功达 晏鄂川 王雪明 谢良甫 高连通 |
| |
| 作者单位： | 1.中国地质大学（武汉） 工程学院，武汉 430074；2.渥太华大学 工程学院，渥太华 K1N 6N5 |
| |
| 基金项目： | 国家重点基础研究发展计划(973)项目（No. 2011CB710605）；教肓部新世纪人才支持计划资助项目（No. NCET-07-0775）；北京市科学技术委员会重点资助项目（No.20090102-2796） |
| |
| 摘 要： | 建立了4组不同孔隙分布形式的多孔材料模型，在考虑孔隙分布范围和密度的基础上计算其孔隙分布分形维数，并利用假三维数值试验的方法获得了相同初始强度、不同孔隙度和孔隙分布形式试样的抗压强度。数值试验结果表明，除了孔隙度较小和孔隙分布分维数较大的试样破坏形式基本满足45° 破裂角的规律以外，该分维数较小的试样均呈现出不对称的斜截面破坏；在孔隙度相同的情况下，该分维数越大，样品的抗压强度越高；通过推导假三维情况下材料孔隙度与抗压强度的理论关系发现，该分维数越大，样组的抗压强度随孔隙度增大而衰减的速率越慢；根据损伤力学模型对试样的抗压强度进行预测分析发现，当样组的该分维数较大时，该模型能够较准确地预测多孔材料的抗压强度，而当样组的该分维数逐渐减小时，损伤力学模型的精度也逐渐降低。上述规律是由孔隙分布分维数越小、孔隙分布越不均匀、试样中应力集中的累积效应越显著的原因而造成的。
|
| 关 键 词： | 孔隙 分形 数值试验 抗压强度 损伤 应力集中 |
| 收稿时间： | 2013-04-22 |
Study of impact of fractal dimension of pore distribution on compressive strength of porous material |
| |
| LU Gong-da,YAN E-chuan,WANG Xue-ming,XIE Liang-fu,GAO Lian-tong.Study of impact of fractal dimension of pore distribution on compressive strength of porous material[J].Rock and Soil Mechanics,2014,35(8):2261-2268. |
| |
| Authors: | LU Gong-da YAN E-chuan WANG Xue-ming XIE Liang-fu GAO Lian-tong |
| |
| Institution: | 1. Faculty of Engineering, China University of Geosciences, Wuhan 430074, China; 2. Faculty of Engineering, University of Ottawa, Ottawa K1N 6N5, Canada |
| |
| Abstract: | Four types of porous material models with different pore distribution patterns are established, and their fractal dimensions of pore distribution (FDPD) are calculated based on both the range and concentration of their pore locations. Then biaxial numerical experiments are conducted to obtain the compressive strength of samples with identical intact strength and different pore distributions and porosities. The results indicate that the failure modes of samples with small porosity or high FDPD conform to the law of 45° angle of rupture, while other samples with low FDPD show asymmetric rupture in oblique section; for samples with identical porosity, the higher the FDPD is, the greater the compressive strength is; the theoretical relationship between sample porosity and its compressive strength proposed demonstrates that the higher the FDPD is, the slower the rate of strength declining with the growth of porosity is; and according to the prediction for compressive strength using damage model, the predicting result is more accurate for porous materials when their FDPD is high, while its accuracy gradually decreases as the FDPD becomes lower. The laws above can be attribute to the fact that a drop in FDPD will lead to more irregular distribution of pores, thus the accumulation of stress concentration in turn will more likely to trigger irregular and easy failures. |
| |
| Keywords: | pore fractal numerical test compressive strength damage stress concentration |
|
| 点击此处可从《岩土力学》浏览原始摘要信息 |
| 点击此处可从《岩土力学》下载免费的PDF全文 |
|
