•  
  •  
 

Coal Geology & Exploration

Abstract

For conquering limitation that the traditional Nishihara model cannot describe the accelerated creep characteristics of coal body, according to the visco-elastic-plastic flow characteristics of coal in the accelerated creep stage, a nonlinear visco-elastic-plastic model was used to replace the ideal viscoelastic-plastic body in Nishihara model to establish the improved Nishihara acceleration model. And creep equation of the improved model under equal confining pressure triaxial condition was also deduced. Afterwards, the improved accelerated creep model was analyzed by the creep test data of coal specimens in the triaxial creep tests using the method of model identification. The results show that the fitting results are basically consistent with the test data, which can preferably reflect non-decay creep characteristics of coal. In addition, the stability of the improved model was also analyzed, the parameter E3 has clear physical significance, and E3 < 0 can be used as the basis for judging creep instability of coal.

Keywords

Nishihara model, accelerated creep, creep characteristic, model identification

DOI

10.3969/j.issn.1001-1986.2019.06.018

Reference

[1] 周世宁,林柏泉. 煤层瓦斯赋存与流动理论[M]. 北京:煤炭工业出版社,1997.

[2] 冶小平,李曼,孙强. 巷道软岩蠕变损伤模型[J]. 煤田地质与勘探,2009,37(2):44-46. YE Xiaoping,LI Man,SUN Qiang. Creep damage model of soft rock roadway[J]. Coal Geology & Exploration,2009,37(2):44-46.

[3] ZHANG Junxiang,LI Bo,SUN Yuning. Dynamic leakage mechanism of gas drainage borehole and engineering application[J]. International Journal of Mining Science and Technology,2018,28(3):505-512.

[4] KANG Jianhong,ZHOU Fubo,LIU Chun,et al. A fractional non-linear creep model for coal considering damage effect and experimental validation[J]. International Journal of Non-Linear Mechanics,2015,76:20-28.

[5] CAI Tingting,FENG Zengchao,JIANG Yulong. An improved hardening-damage creep model of lean coal:A theoretical and experimental study[J]. Arabian Journal of Geosciences,2018,11(20):645.

[6] 赵洪宝,尹光志,张卫中. 围压作用下型煤蠕变特性及本构关系研究[J]. 岩土力学,2009,30(8):2305-2308. ZHAO Hongbao,YIN Guangzhi,ZHANG Weizhong. Study of creep characteristics and constitutive relation of briquette under confining pressure[J]. Rock and Soil Mechanics,2009,30(8):2305-2308.

[7] 陈绍杰,郭惟嘉,杨永杰. 煤岩蠕变模型与破坏特征试验研究[J]. 岩土力学,2009,30(9):2595-2598. CHEN Shaojie,GUO Weijia,YANG Yongjie. Experimental study of creep model and failure characteristics of coal[J]. Rock and Soil Mechanics,2009,30(9):2595-2598.

[8] 尹光志,张东明,何巡军. 含瓦斯煤蠕变实验及理论模型研究[J]. 岩土工程学报,2009,31(4):528-532. YIN Guangzhi,ZHANG Dongming,HE Xunjun. Creep experiment and theoretical model of gas-containing coal[J]. Chinese Journal of Geotechnical Engineering,2009,31(4):528-532.

[9] 杨逾,李盈,周小科. 基于西原加速模型的煤岩蠕变试验研究[J]. 煤炭学报,2014,39(11):2190-2194. YANG Yu,LI Ying,ZHOU Xiaoke. Study on the coal creep test based on the improved Nishihara model[J]. Journal of China Coal Society,2014,39(11):2190-2194.

[10] 尹光志,王登科,张东明,等. 含瓦斯煤岩三维蠕变特性及蠕变模型研究[J]. 岩石力学与工程学报,2008,27(增刊1):2631-2636. YIN Guangzhi,WANG Dengke,ZHANG Dongming,et al. Research on triaxial creep properties and creep model of coal containing gas[J]. Chinese Journal of Rock Mechanics and Engineering,2008,27(S1):2631-2636.

[11] 郭臣业,鲜学福,姜永东,等. 破裂砂岩蠕变试验研究[J]. 岩石力学与工程学报,2010,29(5):990-995. GUO Chenye,XIAN Xuefu,JIANG Yongdong,et al. Experimental research on creep of fractured sandstone[J]. Chinese Journal of Rock Mechanics and Engineering,2010,29(5):990-995.

[12] 王路军,周宏伟,荣腾龙,等. 深部煤体非线性蠕变本构模型及实验研究[J]. 煤炭学报,2018,43(8):2196-2203. WANG Lujun,ZHOU Hongwei,RONG Tenglong,et al. Research on experimental and nonlinear creep constitutive model of coal at depth[J]. Journal of China Coal Society,2018,43(8):2196-2203.

[13] 吴春,郭棋武,洪涛,等. 基于超声检测的软岩单轴流变损伤试验[J]. 煤田地质与勘探,2017,45(5):105-111. WU Chun,GUO Qiwu,HONG Tao,et al. Uniaxial rheological damage experiment of soft rock based on the ultrasonic testing[J]. Coal Geology & Exploration,2017,45(5):105-111.

[14] 陶波,伍法权,郭改梅,等. 西原模型对岩石流变特性的适应性及其参数确定[J]. 岩石力学与工程学报,2005,24(17):3165-3171. TAO Bo,WU Faquan,GUO Gaimei,et al. Flexibility of visco-elastoplastic model to rheological characteristics of rock and solution of rheological parameter[J]. Chinese Journal of Rock Mechanics and Engineering,2005,24(17):3165-3171.

[15] 杨彩红,毛君,李剑光. 改进的蠕变模型及其稳定性[J]. 吉林大学学报(地球科学版),2008,38(1):92-97. YANG Caihong,MAO Jun,LI Jianguang. Modified creep model and its stability[J]. Journal of Jilin University(Earth Science Edition),2008,38(1):92-97.

[16] 邹友平,邹友峰,郭文兵. 改进的西原模型及其稳定性分析[J]. 河南理工大学学报(自然科学版),2005,24(1):22-24. ZOU Youping,ZOU Youfeng,GUO Wenbing. The modified Xiyuan model and its stability analysis[J]. Journal of Henan Polytechnic University(Natural Science),2005,24(1):22-24.

[17] JIANG Qinghui,QI Yajing,WANG Zhijian,et al. An extended Nishihara model for the description of three stages of sandstone creep[J]. Geophysical Journal International,2013,193(2):841-854.

[18] 蒋海飞,刘东燕,黄伟,等. 高围压下不同孔隙水压作用时岩石蠕变特性及改进西原模型[J]. 岩土工程学报,2014,36(3):443-451. JIANG Haifei,LIU Dongyan,HUANG Wei,et al. Creep properties of rock under high confining pressure and different pore water pressures and a modified Nishihara model[J]. Chinese Journal of Geotechnical Engineering,2014,36(3):443-451.

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.