尾矿库筑坝土石料大型三轴试验与力学模型研究
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摘要
针对沙溪铜矿龙王顶尾矿库工程初设土石坝建设方案,配置了3种含石量(5%、15%和30%)的筑坝土石料,开展了常围压条件下的大三轴压缩试验。试验表明,在低围压下土石料表现出明显的剪胀变形,在高围压条件下其变形以剪缩为主。随试样含石量从5%增加至30%,土石料的应力应变曲线形态相似,但强度和剪胀效应均明显增大。基于试验成果分析,构造适用于描述土石料剪缩/剪胀变形规律的塑性加载和流动方向矢量。在广义塑性本构模型框架内,建立了一个适用于土石料的弹塑性力学模型,阐述了模型参数的确定方法。将此力学模型应用于土石料的大型三轴试验模拟,发现该力学模型能较好地模拟土石料的剪缩/剪胀变形规律。
Based on the preliminarily designed construction plan of a soil-rockfill dam for Longwangding tailing dam project in Shaxi Copper Mine, the soil-rockfill materials with three different stone contents(5%, 15% and 30%) are compounded. A series of large-scale triaxial compression tests under various confining pressures are conducted on the soil-rockfill materials. The test results show that the soil-rockfill materials exhibit shear-dilatation and shear-comtraction deformations under low and high confining pressures, respectively. With the increase of stone content from 5% to 30%, the stress-strain curves are similar, but the strength and dilatation effects obviously increase. Based on the test result analysis, the plastic loading and flow direction vectors are constructed to build an elastoplastic mechanical model within the generalized plasticity framework. The method for determining the model parameters is described. Then, the model is applied to the simulations of the large-scale triaxial compression tests, and satisfactory simulation on the shear-comtraction/dilatation deformations of the soil-rockfill materials is obtained.
Based on the preliminarily designed construction plan of a soil-rockfill dam for Longwangding tailing dam project in Shaxi Copper Mine, the soil-rockfill materials with three different stone contents(5%, 15% and 30%) are compounded. A series of large-scale triaxial compression tests under various confining pressures are conducted on the soil-rockfill materials. The test results show that the soil-rockfill materials exhibit shear-dilatation and shear-comtraction deformations under low and high confining pressures, respectively. With the increase of stone content from 5% to 30%, the stress-strain curves are similar, but the strength and dilatation effects obviously increase. Based on the test result analysis, the plastic loading and flow direction vectors are constructed to build an elastoplastic mechanical model within the generalized plasticity framework. The method for determining the model parameters is described. Then, the model is applied to the simulations of the large-scale triaxial compression tests, and satisfactory simulation on the shear-comtraction/dilatation deformations of the soil-rockfill materials is obtained.
引文
[1]HUANG S L,DING X L,ZHANG Y T,et al.Triaxial test and mechanical analysis of rock-soil aggregate sampled from natural sliding mass[J].Advances in Materials Science and Engineering,2015,2015:1-14.
[2]姜景山,程展林,左永振,等.粗粒土剪胀性大型三轴试验研究[J].岩土力学,2014,35(11):3129-3138.(JIANGJing-shan,CHENG Zhan-lin,ZUO Yong-zhen,et al.Dilatancy of coarse-grained soil in large-scale triaxial tests study[J].Rock and Soil Mechanics,2014,35(11):3129-3138.(in Chinese))
[3]刘萌成,高玉峰,黄晓明.考虑强度非线性的堆石料弹塑性本构模型研究[J].岩土工程学报,2005,27(3):294-298.(LIU Meng-cheng,GAO Yu-feng,HUANG Xiao-ming.Study on elasto-plastic constitutive model of rockfills with nonlinear strength characteristics[J].Chinese Jounal of Geotechnical Engineering,2005,27(3):294-298.(in Chinese))
[4]SUKKARAK R,PRAMTHAWEE P,JONGPRADIST P.Amodified elasto-plastic model with double yield surfaces and considering particle breakage for the settlement analysis of high rockfill dams[J].Ksce Journal of Civil Engineering,2017,21(3):1-12.
[5]邹德高,付猛,刘京茂,等.粗粒料广义塑性模型对不同应力路径适应性研究[J].大连理工大学学报,2013,53(5):702-709.(ZOU De-gao,FU Meng,LIU Jing-mao,et al.Study of adaptability of generalized plastic model of coarse grained soil under various stress paths[J].Journal of Dalian University of Technology,2013,53(5):702-709.(in Chinese))
[6]王占军,陈生水,傅中志.堆石料的剪胀特性与广义塑性本构模型[J].岩土力学,2015,36(7):1931-1938.(WANGZhan-jun,CHEN Sheng-shui,FU Zhong-zhi.Dilatancy behaviors and generalized plasticity constitutive model of rockfill materials[J].Rock and Soil Mechanics,2015,36(7):1931-1938.(in Chinese))
[7]朱晟,魏匡民,林道通.筑坝土石料的统一广义塑性本构模型[J].岩土工程学报,2014,36(8):1394-1399.(ZHUSheng,WEI Kuang-min,LIN Dao-tong.Generalized plasticity model for soil and coarse-grained dam materials[J].Chinese Journal of Geotechnical Engineering,2014,36(8):1394-1399.(in Chinese))
[8]郭万里,朱俊高,彭文明.粗粒土的剪胀方程及广义塑性本构模型研究[J].岩土工程学报,2017,32(2):1-7.(GUOWan-li,ZHU Jun-gao,PENG Weng-ming.Study on dilatancy equation and generalized plastic constitutive model for coarse-grained soil[J].Chinese Journal of Geotechnical Engineering,2017,32(2):1-7.(in Chinese))
[9]XU B,ZOU D,LIU H.Three-dimensional simulation of the construction process of the Zipingpu concrete face rockfill dam based on a generalized plasticity model[J].Computers and Geotechnics,2012,43:143-154.
[10]NAKAI T.An isotropic hardening elastoplastic model for sand considering the stress path dependency in three-dimentional stresses[J].Soils and Foundations,1989,29:119-137.
[11]陈生水,傅中志,韩华强,等.一个考虑颗粒破碎的堆石料弹塑性本构模型[J].岩土工程学报,2011,33(10):1489-1495.(CHEN Sheng-shui,FU Zhong-zhi,HAN Hua-qiang,et al.An elastoplastic model for rockfill materials considering particle breakage[J].Chinese Journal of Geotechnical Engineering,2011,33(10):1489-1495.(in Chinese))
[2]姜景山,程展林,左永振,等.粗粒土剪胀性大型三轴试验研究[J].岩土力学,2014,35(11):3129-3138.(JIANGJing-shan,CHENG Zhan-lin,ZUO Yong-zhen,et al.Dilatancy of coarse-grained soil in large-scale triaxial tests study[J].Rock and Soil Mechanics,2014,35(11):3129-3138.(in Chinese))
[3]刘萌成,高玉峰,黄晓明.考虑强度非线性的堆石料弹塑性本构模型研究[J].岩土工程学报,2005,27(3):294-298.(LIU Meng-cheng,GAO Yu-feng,HUANG Xiao-ming.Study on elasto-plastic constitutive model of rockfills with nonlinear strength characteristics[J].Chinese Jounal of Geotechnical Engineering,2005,27(3):294-298.(in Chinese))
[4]SUKKARAK R,PRAMTHAWEE P,JONGPRADIST P.Amodified elasto-plastic model with double yield surfaces and considering particle breakage for the settlement analysis of high rockfill dams[J].Ksce Journal of Civil Engineering,2017,21(3):1-12.
[5]邹德高,付猛,刘京茂,等.粗粒料广义塑性模型对不同应力路径适应性研究[J].大连理工大学学报,2013,53(5):702-709.(ZOU De-gao,FU Meng,LIU Jing-mao,et al.Study of adaptability of generalized plastic model of coarse grained soil under various stress paths[J].Journal of Dalian University of Technology,2013,53(5):702-709.(in Chinese))
[6]王占军,陈生水,傅中志.堆石料的剪胀特性与广义塑性本构模型[J].岩土力学,2015,36(7):1931-1938.(WANGZhan-jun,CHEN Sheng-shui,FU Zhong-zhi.Dilatancy behaviors and generalized plasticity constitutive model of rockfill materials[J].Rock and Soil Mechanics,2015,36(7):1931-1938.(in Chinese))
[7]朱晟,魏匡民,林道通.筑坝土石料的统一广义塑性本构模型[J].岩土工程学报,2014,36(8):1394-1399.(ZHUSheng,WEI Kuang-min,LIN Dao-tong.Generalized plasticity model for soil and coarse-grained dam materials[J].Chinese Journal of Geotechnical Engineering,2014,36(8):1394-1399.(in Chinese))
[8]郭万里,朱俊高,彭文明.粗粒土的剪胀方程及广义塑性本构模型研究[J].岩土工程学报,2017,32(2):1-7.(GUOWan-li,ZHU Jun-gao,PENG Weng-ming.Study on dilatancy equation and generalized plastic constitutive model for coarse-grained soil[J].Chinese Journal of Geotechnical Engineering,2017,32(2):1-7.(in Chinese))
[9]XU B,ZOU D,LIU H.Three-dimensional simulation of the construction process of the Zipingpu concrete face rockfill dam based on a generalized plasticity model[J].Computers and Geotechnics,2012,43:143-154.
[10]NAKAI T.An isotropic hardening elastoplastic model for sand considering the stress path dependency in three-dimentional stresses[J].Soils and Foundations,1989,29:119-137.
[11]陈生水,傅中志,韩华强,等.一个考虑颗粒破碎的堆石料弹塑性本构模型[J].岩土工程学报,2011,33(10):1489-1495.(CHEN Sheng-shui,FU Zhong-zhi,HAN Hua-qiang,et al.An elastoplastic model for rockfill materials considering particle breakage[J].Chinese Journal of Geotechnical Engineering,2011,33(10):1489-1495.(in Chinese))