img

Wechat

Adv. Search

Gold Science and Technology ›› 2022, Vol. 30 ›› Issue (3): 449-459.doi: 10.11872/j.issn.1005-2518.2022.03.142

• Mining Technology and Mine Management • Previous Articles    

Study on Creep Characteristics and Nonlinear Creep Model of Argillaceous Siltstone

Ziyang ZHANG(),Ping CAO,Zhizhen LIU(),Feng XIAO   

  1. School of Resource and Safety Engineering,Central South University,Changsha 410083,Hunan,China
  • Received:2021-10-05 Revised:2022-01-11 Online:2022-06-30 Published:2022-09-14
  • Contact: Zhizhen LIU E-mail:852065530@qq.com;zzliu0217@163.com

Abstract:

The stability and rock long-term strength of underground rock mass engineering are closely related to the rock creep characteristics.With the deepening of resource exploitation,there are many mining rock mass large deformation and strong rheology problems.Therefore,the research of rock creep,especially the creep model under high stress condition,has great engineering significance and research value. Creep tests on moderately weathered argillous siltstone under graded uniaxial loading was carried out.The rock samples were machined into cylinders with dimensions of ?50 mm×100 mm.The stress loading level was 6~20 MPa,the stress increment was determined to be 2 MPa for each stage,and the stress remained constant for 72 h for each stage.The research shows that most of the creep deformation of moderately weathered argillaceous siltstone occurs at the moment of loading.When the creep stress is less than 12 MPa,the rock creep shows decelerating creep phase and even creep phase.When the creep stress is greater than 14 MPa,the rock creep shows decelerating creep phase,even creep phase and accelerating creep phase.The rock long-term strength obtained by using the given creep rate threshold method is 14.3 MPa.In order to describe the nonlinear creep characteristics of rock,a nonlinear viscoplastic element related to time and stress level was introduced.By connecting the nonlinear viscoplastic with a generalized Kelvin component and a viscous component with a switch,an improved nonlinear viscoelastic-plastic creep model was obtained,and the constitutive equation and creep equation of the improved viscoelastic-plastic creep model were given.The Levenberg-Marquardt nonlinear least square method of Origin platform was used to invert the creep model mechanical parameters.By comparing the generalized Kelvin creep model,Burgers creep model,improved viscoelastic-plastic creep model with the test results,obtain the applicable characteristic of each model.The generalized Kelvin creep model is suitable for describing the rock instantaneous deformation and decelerating creep phase at low stress level,and the Burgers creep model can describe the rock instantaneous deformation,decelerating creep and even creep phase very well.It is concluded that the improved viscoelastic-plastic creep model is suitable for middle-weathered argillaceous siltstone,which explains the nonlinear creep mechanical properties of mudstone formation well.The research results provide important guidance for further revealing the rock rheological properties and building rock creep model.

Key words: nonlinear creep model, creep property, accelerated creep, long-term strength, gradation loading, argillaceous siltstone

CLC Number: 

  • TD853

Fig.1

Rock sample"

Fig.2

Creep test system"

Fig.3

Loading scheme of creep test"

Fig.4

Uniaxial creep curves for staged loading of moderately weathered argillaceous siltstone"

Fig.5

Creep curves of rock at 12 MPa and 14 MPa stress levels"

Table 1

Creep test results of moderately weathered argillaceous siltstone under different load levels"

应力水平/MPaε0ε1ε2ε3εiεiε0/ε
61.520.66--2.190.66069.4%
82.220.07--2.290.07096.7%
102.420.11--2.530.11095.7%
122.600.14--2.740.14094.9%
142.800.100.020.0132.920.13395.9%
162.930.160.030.0193.150.20993.0%
183.190.160.040.0343.440.23492.7%
203.490.120.110.1193.850.34991.4%

Fig.6

Rock creep rate in stable creep stage under different load levels"

Fig.7

An improved nonlinear viscoelastic-plastic creep model for moderately weathered argillaceous sandstone"

Fig.8

Change of creep rate with time in accelerated creep stage"

Table 2

Generalized Kelvin creep model fitting parameters under different stress levels"

应力水平/MPaE0/MPaE1/MPaη1/(GPa·s)R2
64.38.319.70.991
83.7113.8270.60.971
104.2102.7120.90.988
124.798.9183.00.991

Table 3

Burgess creep model fitting parameters under different stress levels"

应力水平/MPaE0/MPaE1/MPaη1/(GPa·s)η2/(×104 GPa·s)R2
64.38.419.26.10.991
83.7133.7582.91 126.10.939
104.2102.8120.4604.40.988
124.799.6179.395.10.991
145.1157.4391.813.40.990
165.5127.4742.94.80.993

Table 4

Improved nonlinear viscoelastic-plastic creep model fitting parameters under different stress levels"

应力水平/MPaE0/MPaE1/MPaη1/(GPa·s)η2/(×104 GPa·s)ABm/(×103R2
66.354.702.1-0.681.12.2000.994
8189.7117.8269.754.8-0.012.20.0100.975
103.3103.4117.23.5321.48-322.5-2 236.0000.993
122.03.40.71.90.870.60.0010.995
142.23.61.92.41.754.10.0010.994
161.52.52.31.60.760.20.0020.995
186.32 086.904.8-0.130.45.2000.996
20184.293.13 327.30.117.7414.41 120.1000.995

Fig.9

Comparison between generalized Kelvin creep model fitting results and experimental results"

Fig.10

Comparison between Burgess creep model fitting results and experimental results"

Fig.11

Comparison between improved nonlinear viscoelastic-plastic creep model fitting results and experimental results"

Cao Ping, Zheng Xinping, Li Na,et al,2012.Experiment and model study of rheological characteristics for deep amphibolite[J].Chinese Journal of Rock Mechanics and Engineering,31(Supp.1):3015-3021.
Cao W G, Chen K, Tan X,et al,2020.A novel damage-based creep model considering the complete creep process and multiple stress levels[J].Computers and Geotechnics,124:103599.
Gong Cong, Zhao Kun, Bao Han,et al,2021.Acoustic emission source evolution characteristics and fractal features during creep failure of red sandstone[J].Rock and Soil Mechanics,42(10):1-13.
Han Gang, Hou Jing, Zhou Hui,et al,2021.Shear creep experimental study on constitutive model of interlayer shear weakness zones[J].Chinese Journal of Rock Mechanics and Engineering,40(5):958-971.
Han Y, Ma H L, Yang C H,et al,2020.A modified creep model for cyclic characterization of rock salt considering the effects of the mean stress,half-amplitude and cycle period[J].Rock Mechanics and Rock Engineering,53(7):3223-3236.
Hou R B, Zhang K, Tao J,et al,2018.A nonlinear creep damage coupled model for rock considering the effect of initial damage[J].Rock Mechanics and Rock Engineering,52(5):1275-1285.
Huang Da, Yang Chao, Huang Runqiu,et al,2015.Experimental research of unloading triaxial rheological characteristics of marble affected by different step unloading values[J].Chinese Journal of Rock Mechanics and Engineering,34(Supp.1):2801-2807.
Huang Ming,2010.Study on the Creep Properties of Water-bearing Siltite and Its Application in Soft Rock Tunnel Engineering[D].Chongqing:Chongqing University.
Jiang Yuzhou, Wang Ruihong, Zhu Jiebing,et al,2015.Exprimental study of creep and elastic aftereffect of sandstone[J].Chinese Journal of Rock Mechanics and Engine-ering,34(10):2010-2017.
Jiang Yuzhou, Zhang Mingming, Li Liangquan,et al,2008.Study on nonlinear viscoelasto-plastic creep model of rock and its parameter identification[J].Chinese Journal of Rock Mechanics and Engineering,27(4):832-839.
Li Zuyong, Yang Gengshe, Wei Yao,et al,2021.Study on creep mechanical properties of frozen cretaceous sandstone during thawing process[J].Chinese Journal of Rock Mechanics and Engineering,40(9):1777-1788.
Lin Hanxiang, Zhang Qiangyong, Zhang Longyun,et al,2021.Triaxial creep test and theoretical analysis of argillaceous siltstone of large buried deep tunnel[J].Journal of Central South University(Science and Technology),52(5):1552-1561.
Liu Xinxi, Li Shengnan, Zhou Yanming,et al,2020.Study on creep behavior and long-term strength of argillaceous siltstone under high stresses[J].Chinese Journal of Rock Mechanics and Engineering,39(1):138-146.
Luo Runlin, Ruan Huaining, Sun Yunqiang,et al,2007.Non-stationary parameter creep constitutive model of rocks[J].Journal of Guilin University of Technology,27(2):200-203.
Ma Dan, Duan Hongyu, Zhang Jixiong,et al,2021.Experimental investigation of creep-erosion coupling mechanical properties of water inrush hazards in fault fracture rock masses[J].Chinese Journal of Rock Mechanics and Engineering,40(9):1751-1763.
Shao Zhushan, Li Baixiao,2021.Study on deformation and secular stability of argillaceous siltstoue tunnel[J].Chinese Journal of Rock Mechanics and Engineering,17(3):883-896.
Shen Wenwu, Yuan Pengbo, Liu Xiaowei,et al,2009.Study on creep properties of red-bed soft rock under step load[J].Chinese Journal of Rock Mechanics and Engineering,28(Supp.1):3076-3081.
Su Teng, Zhou Hongwei, Zhao Jiawei,et al,2019.A creep model of rock based on variable order fractional derivative[J].Chinese Journal of Rock Mechanics and Engineering,38(7):1355-1363.
Sun Xiaoming, Miao Chengyu, Jiang Ming,et al,2021.Experimental and theoretical study on creep of sandstone with different moisture content based on modified Nishihara model[J].Chinese Journal of Rock Mechanics and Engineering,40(12):1-10.
Wang Junbao, Liu Xinrong, Guo Jianqiang,et al,2014.Creep properties of salt rock and its nonlinear constitutive model[J].Journal of China Coal Society,39(3):445-451.
Wang X G, Huang Q B, Lian B Q,et al,2018.Modified Nishihara rheological model considering the effect of thermal-mechanical coupling and its experimental verification[J].Advances in Materials Science and Engineering,2018:4947561..
Xue Dongjie, Lu Lele, Yi Haiyang,et al,2021.A fractional Burgers model for uniaxial and triaxial creep of damaged salt-rock considering temperature and volume-stress[J].Chinese Journal of Rock Mechanics and Engineering,40(2):315-329.
Zhang Junwen, Huo Yinghao,2021.Study on creep behavior of deep sandstones under stepwise incremental loading and unloading condition[J].Journal of China Coal Society:1-10..
Zhao Yanlin, Cao Ping, Wen Youdao,et al,2008.Elastovisco-plastic rheological experiment and nonlinear rheological model of rocks[J].Chinese Journal of Rock Mechanics and Engineering,27(3):477-486.
曹平,郑欣平,李娜,等,2012.深部斜长角闪岩流变试验及模型研究[J].岩石力学与工程学报,31(增1):3015-3021.
龚囱,赵坤,包涵,等,2021.红砂岩蠕变破坏声发射震源演化及其分形特征[J].岩土力学,42(10):1-13.
韩钢,侯靖,周辉,等,2021.层间错动带剪切蠕变试验及蠕变模型研究[J].岩石力学与工程学报,40(5):958-971.
黄达,杨超,黄润秋,等,2015.分级卸荷量对大理岩三轴卸荷蠕变特性影响规律试验研究[J].岩石力学与工程学报,34(增1):2801-2807.
黄明,2010.含水泥质粉砂岩蠕变特性及其在软岩隧道稳定性分析中的应用研究[D].重庆:重庆大学.
蒋昱州,王瑞红,朱杰兵,等,2015.砂岩的蠕变与弹性后效特性试验研究[J].岩石力学与工程学报,34(10):2010-2017.
蒋昱州,张明鸣,李良权,2008.岩石非线性黏弹塑性蠕变模型研究及其参数识别[J].岩石力学与工程学报,27(4):832-839.
李祖勇,杨更社,魏尧,2021.白垩系冻结砂岩解冻过程中蠕变力学特性研究[J].岩石力学与工程学报,40(9):1777-1788.
林韩祥,张强勇,张龙云,等,2021.大埋深隧洞泥质粉砂岩的三轴蠕变试验与理论分析[J].中南大学学报(自然科学版),52(5):1552-1561.
刘新喜,李盛南,周炎明,等,2020.高应力泥质粉砂岩蠕变特性及长期强度研究[J].岩石力学与工程学报,39(1):138-146.
罗润林,阮怀宁,孙运强,等,2007.一种非定常参数的岩石蠕变本构模型[J].桂林工学院学报,27(2):200-203.
马丹,段宏宇,张吉雄,等,2021.断层破碎带岩体突水灾害的蠕变—冲蚀耦合力学特性试验研究[J].岩石力学与工程学报,40(9):1751-1763.
邵珠山,李柏霄,2021.泥质粉砂岩隧道变形及长期稳定性研究[J].地下空间与工程学报,17(3):883-896.
谌文武,原鹏博,刘小伟,等,2009.分级加载条件下红层软岩蠕变特性试验研究[J].岩石力学与工程学报,28(增1):3076-3081.
苏腾,周宏伟,赵家巍,等,2019.基于变阶分数阶导数的岩石蠕变模型[J].岩石力学与工程学报,38(7):1355-1363.
孙晓明,缪澄宇,姜铭,等,2021.基于改进西原模型的不同含水率砂岩蠕变实验及理论研究[J].岩石力学与工程学报,40(12):1-10.
王军保,刘新荣,郭建强,等,2014.盐岩蠕变特性及其非线性本构模型[J].煤炭学报,39(3):445-451.
薛东杰,路乐乐,易海洋,等,2021.考虑温度和体积应力的分数阶蠕变损伤Burgers模型[J].岩石力学与工程学报,40(2):315-329.
张俊文,霍英昊,2021.深部砂岩分级增量加卸载蠕变特性研究[J].煤炭学报:1-10..
赵延林,曹平,文有道,等,2008.岩石弹黏塑性流变试验和非线性流变模型研究[J].岩石力学与工程学报,27(3):477-486.
[1] Yuanjiang CHEN,Zhihua SHI. Shear Rheological Properties of Sandy Pebble Soil [J]. Gold Science and Technology, 2019, 27(3): 378-384.
Viewed
Full text


Abstract

Cited

  Shared   
  Discussed   
No Suggested Reading articles found!