露天矿复合边坡动水携砂现象危及边坡安全及周边环境。为揭示渗流作用下砂粒间相互作用机理,以砂颗粒团簇特征结构单元为对象,从颗粒尺度分析特征结构单元在自重、浮力、法向接触力、剪切接触力和渗透力作用下,砂粒间的非线性移动、变形过程及砂粒间在强力链上的力学行为。提出一种新的“塑转铰”元件,对Будин模型进行改进,建立“弹-黏-塑转铰”砂土蠕变力学模型,并给出其本构方程和蠕变曲线方程。通过动水携砂模型试验及砂土剪切蠕变试验数据,对改进Будин模型进行参数辨识和验证。分析结果表明:该模型精度较好,能描述蠕变过程中砂粒间的接触、摩擦、转动过程,能揭示含水砂层内的分级“阶梯”破坏现象及砂土颗粒间的剪切衰减及非衰减及第Ⅲ阶段正、负加速剪切蠕变过程及其变形规律,为分析散体颗粒间的相互作用机制提供了一种新的力学模型。
Abstract
The seepage induced by moving water and sand in composite slope in surface mine threatens the slope safety and surrounding environment. In order to reveal the interaction mechanism among sand particles under the action of seepage,with characteristic structure unit of sand clusters as object, we analyzed the process of nonlinear movement and deformation and mechanical behavior of the strong chain among sand particles under actions of gravity, buoyancy, normal and shear contact force and seepage force in particle size scale. Furthermore, we proposed a new plastic-to-hinge element to improve the Будин model and established a mechanical model of sand creep with elastic-visco-plastic hinge. According to model test of moving water and sand and data from sand creep test, we gave constitutive equation and creep curve equation of the model and identified the parameters of the improved Будин model and verified its accuracy. Results show that the model could describe the contact, friction and rotation among sand particles during creep process with good accuracy; secondly, the model reveals the graded ladder-like failure phenomenon in the water-sand layer and shear attenuation and non-attenuation among sand particles, as well as the positive and negative accelerating shear creep process in the third stage.The present model offers a new mechanical approach for analyzing the interaction mechanism among discrete particles.
关键词
露天矿 /
动水携砂 /
复合边坡 /
改进Будин模型 /
砂土蠕变
Key words
surface mine /
seepage induced by moving water and sand /
composite slope /
improved Будин model /
sand creep
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] 武 强,崔芳鹏,赵苏启,等. 矿井水害类型划分及主要特征分析[J]. 煤炭学报, 2013, 38(4): 561-565.
[2] 汪闻韶.土的液化机理[J]. 水利学报,1981,(5):22-34.
[3] BARDET J P, KAPUSKAR M. Liquefaction Sand Boils in San Francisco During 1989 Loma Prieta Earthquake [J]. Journal of Geotechnical Engineering,1993, 119(3):534-562.
[4] HOLZER T L, CLARK M M. Sand Boils Without Earthquakes[J]. Geology, 1993,21(10):873-876.
[5] CASAGRANDE A. Liquefaction and Cyclic Deformation of Sands—A Critical Review[C]∥Harvard Soil Mechanics. Proceedings of the 5th Pan American Conference on Soil Mechanics and Foundation Engineering.Buenos Aires,Argentina,November 17-22,1975:80-133.
[6] 邓荣贵,张倬元,刘 宏.饱和砂土动力液化到渗流液化过程探讨[J]. 山地学报, 2001, 19(5): 430-435.
[7] 刘红军,李洪江,王 虎,等.饱和海床土渗流-应力耦合损伤及液化破坏规律(Ⅰ)[J]. 哈尔滨工程大学学报, 2014, 35(11): 1-7.
[8] 李洪江,刘红军,王 虎,等.饱和海床土渗流-应力耦合损伤及液化破坏规律(Ⅱ)[J]. 哈尔滨工程大学学报, 2014, 35(12): 1480-1486.
[9] 周 健,姚志雄,张 刚.砂土渗流过程的细观数值模拟[J]. 岩土工程学报, 2007, 29(7): 977-981.
[10]李广信,周晓杰.堤基管涌发生发展过程的试验模拟[J]. 水利水电科技进展, 2005, 25(6): 21-24.
[11]刘忠玉,乐金朝,苗天德.无粘性土中管涌的毛管模型及其应用[J]. 岩石力学与工程学报, 2004, 23(22): 3871-3876.
[12]李守德,徐红娟,田 军.均质土坝管涌发展过程的渗流场空间形状研究[J]. 岩土力学, 2005, 26(12): 2001-2004.
[13]刘丹珠,张家发,李少龙,等. 考虑土体坍塌的单层堤基管涌数值模拟方法研究[J]. 长江科学院院报, 2012, 29(10): 98-101.
[14]隋旺华,蔡光桃,董青红.近松散层采煤覆岩采动裂缝水砂突涌临界水力坡度试验[J]. 岩石力学与工程学报, 2007, 26(10): 2084-2091.
[15]隋旺华,董青红.近松散层开采孔隙水压力变化及其对水砂突涌的前兆意义[J]. 岩石力学与工程学报, 2008, 27(9): 1908-1916.
[16]杨伟峰.薄基岩采动破断及其诱发水砂混合流运移特征[D]. 徐州:中国矿业大学, 2009.
[17]孙其诚,王光谦.颗粒物质力学导论[M]. 北京:科学出版社,2009.
[18]孙其诚,厚美瑛,金 峰,等.颗粒物质物理与力学[M]. 北京:科学出版社,2011.
[19]王来贵,朱旺喜.科学研究要拥有系统哲学思维[J]. 中国基础科学,2015, (3): 60-62.
[20]王来贵,朱旺喜.试论工程系统演化过程研究内涵[J]. 中国基础科学,2013, (2): 3-6.
[21]维亚洛夫C C. 土力学的流变原理[M]. 杜于培,译.北京:科学出版社,1987.
[22]米海珍,吴紫汪,马 巍,等.冻结细砂剪切蠕变的若干特性[J]. 冰川冻土,1993, 15(3): 492-497.
基金
国家自然科学基金项目(51274110,51474121,51704143);国家煤炭联合基金重点支持项目(U1361211);博士后启动基金资助项目(165806);辽宁工程技术大学生产技术问题调研基金项目(20160058t)
PDF(2382 KB)
