粉砂质泥岩峰前、峰后应力松弛特性试验研究

doi:10.13722/j.cnki.jrme.2014.1538

摘要
图/表
参考文献(26)
相关文章 (15)

全文: PDF (945 KB) HTML (1 KB)
输出: BibTeX | EndNote (RIS)

摘要采用分级加载方法，对三峡地区巴东组粉砂质泥岩开展峰前、峰后三轴压缩应力松弛试验。依据试验结果，分析峰前弹性段、屈服段，峰后应变软化段、残余强度段岩石应力松弛量、应力松弛度、松弛稳定时间以及应力松弛速率的变化规律，研究峰前、峰后不同阶段岩石应力松弛特征的差异。引入损伤变量对三参量广义Kelvin模型进行改进，建立岩石的非线性应力松弛损伤模型。应用Levenberg-Marquardt算法，辨识得出岩石的应力松弛损伤模型参数。基于辨识结果，分析峰后破裂对岩石应力松弛模型参数的影响作用，研究峰前、峰后不同阶段岩石应力松弛模型参数的变化规律。在试验研究成果的基础上，总结得出峰前、峰后岩石不同的应力松弛机制。研究结果表明：(1) 峰前、峰后各阶段中，峰后应变软化段试样的应力松弛量大，应力损失程度高，松弛稳定时间长，应力松弛速率快，工程实践中应尽可能避免使岩石处于峰后应变软化段。(2) 峰后各级应变水平试样的G1，G2，H1参数值为峰前0.20%应变水平相应参数值的1%～53%，峰后岩石的应力松弛模型参数值急剧降低。(3) 峰后形成的宏观破裂对试样的黏弹性力学特性影响最大，黏性力学特性其次，而对试样的瞬时弹性力学特性影响最小。(4) 峰后应变软化段试样的G1，H1模型参数值大幅降低，峰前屈服段试样的G2模型参数值大幅降低。(5) 峰前岩石的应力松弛主要是由于岩石内部微裂隙的产生、扩展等原因而引起的，峰后岩石的应力松弛主要是由于岩石中宏观裂纹的产生、扩展以及贯通等原因而引起的。峰前、峰后岩石的应力松弛机制不同。

	服务

	把本文推荐给朋友
	加入我的书架
	加入引用管理器
	E-mail Alert
	RSS
	作者相关文章
	于怀昌
	董金玉
	刘汉东
	黄志全
	史广诚

关键词 ：岩石力学, 粉砂质泥岩, 峰前, 峰后, 应力松弛, 机制

Abstract：The pre-peak and post-peak stress relaxation tests under triaxial compression were conducted on silty mudstone samples from Badong Formation strata in the Three Gorges Reservoir area. The pre-peak stress relaxation of rocks was divided into elastic and yield stages，and the post-peak stress relaxation of rocks was separated into strain softening and residual strength stages according to the test results. The variations of relaxation magnitude，degree，time and rate of rocks with time in four stages were analyzed，and the differences between pre-peak and post-peak stress relaxation characteristics of rocks were investigated in detail. A damage variable was proposed considering the deterioration of relaxation moduli of rocks with time. A new nonlinear damage model was established by introducing the damage variable into three-parameter generalized Kelvin model. The Levenberg-Marquardt algorithm was used to identify the pre-peak and post-peak model parameters of rocks. The variations of model parameters in four stages were analyzed，and the differences between pre-peak and post-peak model parameters were investigated according to the identification results. Finally，the mechanisms of pre-peak and post-peak stress relaxation behavior of rocks were discussed. The results show that：(1) through comparing four values of relaxation magnitude，degree，time and rate of rocks among different stages，it is found that four values of paramters in the strain softening stage are larger than those in three other stages，which should be paid more attention in rock engineering. (2) The post-peak values of G1，G2 and H1 in 5–9 strain levels are 1–53 percent of corresponding pre-peak values in first strain level. (3) The influence of post-peak rapture on the viscoelasticity of rocks is the largest，followed by the viscosity，and that on the instantaneous elasticity of rocks is the smallest. (4) The values of G1 and H1 decrease sharply in the strain softening stage，and the value of G2 drops dramatically in the yield stage. (5) The pre-peak and post-peak stress relaxation behavior of silty mudstone is mainly derived from the initiation and growth of microfissures and the initiation，growth and coalescence of macrocracks in rocks，respectively. Therefore，the mechanisms of pre-peak and post-peak stress relaxation behavior of rocks are different.

Key words： rock mechanics silty mudstone pre-peak post-peak stress relaxation mechanism

引用本文:

于怀昌，董金玉，刘汉东，黄志全，史广诚. 粉砂质泥岩峰前、峰后应力松弛特性试验研究[J]. 岩石力学与工程学报, 2016, 35(S1): 2663-2672.
YU Huaichang，DONG Jinyu，LIU Handong，HUANG Zhiquan，SHI Guangcheng. Experimental study of pre-peak and post-peak stress relaxation behavior of silty mudstone. , 2016, 35(S1): 2663-2672.

链接本文:

https://rockmech.whrsm.ac.cn/CN/10.13722/j.cnki.jrme.2014.1538 或 https://rockmech.whrsm.ac.cn/CN/Y2016/V35/IS1/2663

[1] SUN J，HU Y Y. Time-dependent effects on the tensile strength of saturated granite at the Three Gorges project in China[J]. International Journal of Rock Mechanics and Mining Sciences，1997，34(2)：323–337.

[2] 徐卫亚，杨圣奇，杨松林，等. 绿片岩三轴流变力学特性的研究(I)：试验结果[J]. 岩土力学，2005，26(4)：531–537.(XU Weiya，YANG Shengqi，YANG Songlin，et al. Investigation on triaxial rheological mechanical properties of greenschist specimen(I)：experimental results[J]. Rock and Soil Mechanics，2005，26(4)：531–537.(in Chinese))

[3] 王志俭，殷坤龙，简文星，等. 三峡库区万州红层砂岩流变特性试验研究[J]. 岩石力学与工程学报，2008，27(4)：840–847.(WANG Zhijian，YIN Kunlong，JIAN Wenxing，et al. Experimental study on rheological behaviors of Wanzhou red sandstone in Three Gorges Reservoir area[J]. Chinese Journal of Rock Mechanics and Engineering，2008，27(4)：840–847.(in Chinese))

[4] 朱珍德，李志敬，朱明礼，等. 岩体结构面剪切流变试验及模型参数反演分析[J]. 岩土力学，2009，30(1)：99–104.(ZHU Zhende，LI Zhijing，ZHU Mingli，et al. Shear rheological experiment on rock mass discontinuities and back analysis of model parameters[J]. Rock and Soil Mechanics，2009，30(1)：99–104.(in Chinese))

[5] 韩庚友，王思敬，张晓平，等. 分级加载下薄层状岩石蠕变特性研究[J]. 岩石力学与工程学报，2010，29(11)：2 239–2 247.(HAN Gengyou，WANG Sijing，ZHANG Xiaoping，et al. Study of creep properties of thinly laminated rock under step loading[J]. Chinese Journal of Rock Mechanics and Engineering，2010，29(11)：2 239– 2 247.(in Chinese))

[6] 范庆忠，高延法. 分级加载条件下岩石流变特性的试验研究[J]. 岩土工程学报，2005，27(11)：1 273–1 276.(FAN Qingzhong，GAO Yanfa. Experimental study on creep properties of rocks under stepwise loading[J]. Chinese Journal of Geotechnical Engineering，2005，27(11)：1 273–1 276.(in Chinese))

[7] 朱杰兵，汪斌，邬爱清. 锦屏水电站绿砂岩三轴卸荷流变试验及非线性损伤蠕变本构模型研究[J]. 岩石力学与工程学报，2010，29(3)：528–534.(ZHU Jiebing，WANG Bin，WU Aiqing. Study of unloading triaxial rheological tests and its nonlinear damage constitutive model of Jinping Hydropower Station green sandstone[J]. Chinese Journal of Rock Mechanics and Engineering，2010，29(3)：528–534.(in Chinese))

[8] PENG S S. Time-dependent aspects of rock behavior as measured by a servocontrolled hydraulic testing machine[J]. International Journal of Rock Mechanics Mining Sciences and Geomechanics Abstracts，1973，10(3)：235–246.

[9] ЯЛУШКО В Т，BИНOГРАДОВ B B. Разрушeниe горныx пород и прогнозированиe проявлeний горногo давления[M]. Москва：Недра，1982：58–67.

[10] BIENIAWSKI Z T. Time-dependent behaviour of fractured rock[J]. Rock Mechanics，1970，2(3)：123–137.

[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. (in Chinese))

[12] 刘传孝，黄东辰，张秀丽，等. 深井泥岩峰前/峰后单轴蠕变特征实验研究[J]. 实验力学，2011，26(3)：267–273.(LIU Chuanxiao，HUANG Dongchen，ZHANG Xiuli，et al. Experimental study of uniaxial creep properties of mudstone in deep site front and rear the ultimate strength[J]. Journal of Experimental Mechanics，2011，26(3)：267–273.(in Chinese))

[13] 李永盛. 单轴压缩条件下四种岩石的蠕变和松弛试验研究[J]. 岩石力学与工程学报，1995，14(1)：39–47.(LI Yongsheng. Creep and relaxation of four kinds of rock under uniaxial compression tests[J]. Chinese Journal of Rock Mechanics and Engineering，1995，14(1)：39–47.(in Chinese))

[14] 杨春和，殷建华，DAEMEN J J K. 盐岩应力松弛效应的研究[J]. 岩石力学与工程学报，1999，18(3)：262–265.(YANG Chunhe，YIN Jianhua，DAEMEN J J K. The investigation of stress relaxation of salt rock[J]. Chinese Journal of Rock Mechanics and Engineering，1999，18(3)：262–265.(in Chinese))

[15] 李铀，朱维申，彭意，等. 某地红砂岩多轴受力状态蠕变松弛特性试验研究[J]. 岩土力学，2006，27(8)：1 248–1 252.(LI You，ZHU Weishen，PENG Yi，et al. Multi-axial experimental study on creep and relaxation properties of red sandstone from somewhere[J]. Rock and Soil Mechanics，2006，27(8)：1 248–1 252.(in Chinese))

[16] 熊良宵，杨林德，张尧. 绿片岩多轴受压应力松弛试验研究[J]. 岩土工程学报，2010，32(8)：1 158–1 165.(XIONG Liangxiao，YANG Linde，ZHANG Yao. Stress relaxation tests on green schist specimens under multi-axial compression[J]. Chinese Journal of Geotechnical Engineering，2010，32(8)：1 158–1 165.(in Chinese))

[17] 于怀昌，周敏，刘汉东，等. 粉砂质泥岩三轴压缩应力松弛特性试验研究[J]. 岩石力学与工程学报，2011，30(4)：803–811.(YU Huaichang，ZHOU Min，LIU Handong，et al. Experimental investigation on stress relaxation properties of silty mudstone under triaxial compression[J]. Chinese Journal of Rock Mechanics and Engineering，2011，30(4)：803–811.(in Chinese))

[18] 曹平，郑欣平，李娜，等. 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，2012，31(增1)：3 015–3 021.(CAO Ping，ZHENG Xinping，LI Na，et al. Experiment and model study of rheological characteristics for deep amphibolite[J]. Chinese Journal of Rock Mechanics and Engineering，2012，31(Supp.1)：3 015–3 021.(in Chinese))

[19] 田洪铭，陈卫忠，赵武胜，等. 宜–巴高速公路泥质红砂岩三轴应力松弛特性研究[J]. 岩土力学，2013，34(4)：981–986.(TIAN Hongming，CHEN Weizhong，ZHAO Wusheng，et al. Analysis of triaxial stress relaxation properties of red silty mudstone of Yichang-Badong highway[J]. Rock and Soil Mechanics，2013，34(4)：981–986.(in Chinese))

[20] 唐礼忠，潘长良. 岩石在峰值荷载变形条件下的松弛试验研究[J].岩土力学，2003，24(6)：940–942.(TANG Lizhong，PAN Changliang. Experiment study on properties of stress relaxation of rock under deformation at peak load[J]. Rock and Soil Mechanics，2003，24(6)：940–942.(in Chinese))

[21] 李晓，王思敬，李焯芬. 破裂岩石的时效特性及长期强度[C]// 中国岩石力学与工程学会第5次学术大会论文集. 北京：[s. n.]，1998：214–219.(LI Xiao，WANG Sijing，LEE C F. Time-dependent behaviour and long-term strength of fractured rock[C]// The 5th Academic Meeting of China Society of Rock Mechanics and Engineering. Beijing：[s. n.]，1998：214–219.(in Chinese))

[22] 李华亮，易顺华，邓清禄. 三峡库区巴东组地层的发育特征及其空间变化规律[J]. 工程地质学报，2006，14(5)：577–581.(LI Hualiang，YI Shunhua，DENG Qinglu. Development characteristics and their spatial variations of Badong formation in the three gorges reservoir region[J]. Journal of Engineering Geology，2006，14(5)：577–581.(in Chinese))

[23] ISRM. Suggested methods for determining the strength of rock material in triaxial compression[J]. International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts，1978，15(2)：47–51.

[24] 于怀昌，赵阳，刘汉东，等. 三轴应力作用下水对岩石应力松弛特性影响作用试验研究[J]. 岩石力学与工程学报，2015，34(2)：313–322.(YU Huaichang，ZHAO Yang，LIU Handong，et al. Experimental study of influence of water on stress relaxation of rock under triaxial stress[J]. Chinese Journal of Rock Mechanics and Engineering，2015，34(2)：313–322.(in Chinese))

[25] HAO S W，ZHANG B J，TIAN J F. Relaxation creep rupture of heterogeneous material under constant strain[J]. Physical Review E.，2012，85(1)：012501.

[26] 朱合华，叶斌. 饱水状态下隧道围岩蠕变力学性质的试验研究[J]. 岩石力学与工程学报，2002，21(12)：1 791–1 796.(ZHU Hehua，YE Bin. Experimental study on mechanical properties of rock creep in saturation[J]. Chinese Journal of Rock Mechanics and Engineering，2002，21(12)：1 791–1 796.(in Chinese))