高密实度模拟月壤力学特性试验研究
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摘要
为保证月面采样任务顺利实施,该文以钻取采样的JLU5系列模拟月壤(JLU5-1、JLU5-2和JLU5-3,探月工程内场试验采用)为对象,利用振实装置进行高密实度模拟月壤整备,开展不同密实度条件下(相对密度为0.85、0.9、0.95和0.99)模拟月壤剪切和贯入特性力学试验,分析了相对密度对剪切强度、内聚力、内摩擦角、圆锥指数和圆锥指数梯度的影响规律。试验结果表明,剪切强度和内聚力随相对密度增加总体呈现增加规律,平均变化率分别为11.1%和35.8%;3种模拟月壤内摩擦角随相对密度增加无明显变化趋势,范围为53.3o～67.7o;圆锥指数和圆锥指数梯度随相对密度增加而增加,且圆锥指数和圆锥指数梯度平均变化率较剪切强度和内聚力的大;相同试验条件下,颗粒较细的JLU5-3型模拟月壤较JLU5-1和JLU5-2具有更大的剪切强度、内聚力和圆锥指数,JLU5-2内摩擦角总体上较JLU5-1和JLU5-3的小。利用EDEM软件建立贯入特性试验数值模型,仿真结果表明:不同模拟月壤圆锥指数仿真值总体小于实际试验值,且随相对密度变化规律一致,建立了仿真与试验值线性关系。研究结果可为采样任务顺利实施、钻取机构优化设计、采样触月部件与月壤相互作用力学模型建立提供参考。
In order to analyze the mechanical properties of lunar soil simulant at different densities,3 types of high density lunar soil simulant(JLU5-1, JLU5-2 and JLU5-3, which has been adopted in the Chinese lunar exploration program) was prepared by a self-designed vibrating device, the shearing and penetrating tests of 4 different soil relative density(0.85, 0.9, 0.95 and 0.99) were performed, the influence of relative density on shear strength, cohesion, internal friction angle, cone index and cone index gradient were analyzed. The result showed that the shear strength of 3 lunar soil simulant ranged from 36.6 to 158.4 kPa. The shear strength increased with the increase of relative density, the average change rate was 11.1%, which indicated that the shear capacity was enhanced with the increase of soil relative density. JLU5-3 had the largest shear strength, while the shear strength of JLU5-2 was smallest. The cohesion ranged from 14.9 to 68.0 kPa, which was about 3 to 10 times higher than that of lunar soil simulant JSC-1A and TJ-1. The cohesion increased by 35.8% with the increase of relative density, the average change rate for different lunar soil simulant was 24.7%(JLU5-1), 22.8%(JLU5-2) and 37.5%(JLU5-3), respectively. When the relative density reached 0.9, the cohesion of JLU5-3 was larger than that of JLU5-1 and JLU5-2, and the difference between them increased apparently, which may due to the effect of interface energy and viscidity became more obvious with the decreasing of soil grain size. The internal friction angle ranged from 53.3o to 67.7o, which had no obvious variation trend with the increase of relative density. The internal friction angle of JLU5-2 was always smaller than that of the JLU5-1 and JLU5-3 under different soil relative density conditions. The internal friction angle of JLU5 under high compactness condition was apparently larger than other series lunar soil simulant regolith under natural condition. When penetration depth reached 40 mm in the tests, the cone index of 3 types high-density simulant lunar soil were 129.8 MPa(JLU5-1), 142.9 MPa(JLU5-2) and 175.2 MPa(JLU5-3), respectively. Cone index presented the fluctuations but generally increased with the increase of penetration depth, smaller grain size lead to the increasing of cone index under same testing condition, which was similar to variation trend of cohesion. The cone index of JLU5-3 increased by 13.4% on average compared with that of JLU5-2, and the cone index of JLU5-2 increased on average by 20.5% compared with that of JLU5-1. Cone index gradient was defined as the curve gradient of the cone index versus with penetration depth. When the relative density changed from 0.85 to 0.9 and 0.95 to 0.99, the cone index gradient obviously increased, while there was no significant increase for cone index gradient when relative density changed from 0.9 to 0.95. The average increasing ratio of cone index gradient was 50.6% with the increasing of relative density, greater than that of the cohesion, which indicated that cone index gradient was more sensitive to soil relative density. For different types of lunar soil simulant, JLU5-3 had larger shear strength, cohesion and cone index and cone index gradient than that of JLU5-1 and JLU5-2 under same testing conditions, which may due to JLU5-3 had smaller particle size. Numerical model for penetration characteristic test had been conducted by using discrete element method software(EDEM), simulation results showed that, the simulative value of cone index was always smaller than that of the testing value, however, their variation trend versus with the relative density was consistent. A linear relation model between simulative and testing value was established, the determination coefficient value of the proposed model was 0.87. The simulation method could provide technique method for cone index prediction of lunar soil simulant under high compactness condition. The results of this paper were expected to provide references for drilling sampling mission of lunar soil, optimization design of drilling mechanism, and establishment of mechanical interaction model between drilling component and lunar soil.
In order to analyze the mechanical properties of lunar soil simulant at different densities,3 types of high density lunar soil simulant(JLU5-1, JLU5-2 and JLU5-3, which has been adopted in the Chinese lunar exploration program) was prepared by a self-designed vibrating device, the shearing and penetrating tests of 4 different soil relative density(0.85, 0.9, 0.95 and 0.99) were performed, the influence of relative density on shear strength, cohesion, internal friction angle, cone index and cone index gradient were analyzed. The result showed that the shear strength of 3 lunar soil simulant ranged from 36.6 to 158.4 kPa. The shear strength increased with the increase of relative density, the average change rate was 11.1%, which indicated that the shear capacity was enhanced with the increase of soil relative density. JLU5-3 had the largest shear strength, while the shear strength of JLU5-2 was smallest. The cohesion ranged from 14.9 to 68.0 kPa, which was about 3 to 10 times higher than that of lunar soil simulant JSC-1A and TJ-1. The cohesion increased by 35.8% with the increase of relative density, the average change rate for different lunar soil simulant was 24.7%(JLU5-1), 22.8%(JLU5-2) and 37.5%(JLU5-3), respectively. When the relative density reached 0.9, the cohesion of JLU5-3 was larger than that of JLU5-1 and JLU5-2, and the difference between them increased apparently, which may due to the effect of interface energy and viscidity became more obvious with the decreasing of soil grain size. The internal friction angle ranged from 53.3o to 67.7o, which had no obvious variation trend with the increase of relative density. The internal friction angle of JLU5-2 was always smaller than that of the JLU5-1 and JLU5-3 under different soil relative density conditions. The internal friction angle of JLU5 under high compactness condition was apparently larger than other series lunar soil simulant regolith under natural condition. When penetration depth reached 40 mm in the tests, the cone index of 3 types high-density simulant lunar soil were 129.8 MPa(JLU5-1), 142.9 MPa(JLU5-2) and 175.2 MPa(JLU5-3), respectively. Cone index presented the fluctuations but generally increased with the increase of penetration depth, smaller grain size lead to the increasing of cone index under same testing condition, which was similar to variation trend of cohesion. The cone index of JLU5-3 increased by 13.4% on average compared with that of JLU5-2, and the cone index of JLU5-2 increased on average by 20.5% compared with that of JLU5-1. Cone index gradient was defined as the curve gradient of the cone index versus with penetration depth. When the relative density changed from 0.85 to 0.9 and 0.95 to 0.99, the cone index gradient obviously increased, while there was no significant increase for cone index gradient when relative density changed from 0.9 to 0.95. The average increasing ratio of cone index gradient was 50.6% with the increasing of relative density, greater than that of the cohesion, which indicated that cone index gradient was more sensitive to soil relative density. For different types of lunar soil simulant, JLU5-3 had larger shear strength, cohesion and cone index and cone index gradient than that of JLU5-1 and JLU5-2 under same testing conditions, which may due to JLU5-3 had smaller particle size. Numerical model for penetration characteristic test had been conducted by using discrete element method software(EDEM), simulation results showed that, the simulative value of cone index was always smaller than that of the testing value, however, their variation trend versus with the relative density was consistent. A linear relation model between simulative and testing value was established, the determination coefficient value of the proposed model was 0.87. The simulation method could provide technique method for cone index prediction of lunar soil simulant under high compactness condition. The results of this paper were expected to provide references for drilling sampling mission of lunar soil, optimization design of drilling mechanism, and establishment of mechanical interaction model between drilling component and lunar soil.
引文
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[19]邹猛,李建桥,李因武,等.刚性轮-月壤相互作用预测模型及试验研究[J].农业工程学报,2007,23(12):119-123.Zou Meng,Li Jianqiao,Li Yinwu,et al.Prediction model and experimental study on the interaction of rigid-wheel and lunar soil[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2007,23(12):119-123.(in Chinese with English abstract)
[20]黄晗,李建桥,陈百超,等.滑转条件下星球车坡面通过性评估试验[J].农业工程学报,2016,32(16):40-44.Huang Han,Li Jianqiao,Chen Baichao,et al.Experiment of slope trafficability assessment of planetary rover under slip condition[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2016,32(16):40-44.(in Chinese with English abstract)
[21]黄晗,李建桥,吴宝广,等.轻载荷条件下轻型车辆车轮牵引通过性模型的建立与验证[J].农业工程学报,2015,31(12):64-70.Huang Han,Li Jianqiao,Wu Baoguang,et al.Research on lightweight vehicle wheel tractive trafficability model under light load[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2015,31(12):64-70.(in Chinese with English abstract)
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[23]林呈祥,凌道盛,钟世英.模拟月壤抗剪强度试验研究及离散元分析[J].岩土力学,2017,38(3):893-901.Lin Chengxiang,Ling Daosheng,Zhong Shiying.Experimental research and discrete element analysis of shear strength of lunar soil simulants[J].Rock and Soil Mechanics,2017,38(3):893-901.(in Chinese with English abstract)
[24]Klosky J L,Sture S,Ko H Y,et al.Geotechnical Behavior of JSC-1 lunar soil simulant[J].Journal of Aerospace Engineering,2000,13(4):133-138.
[25]Zeng X W,Chun M H,Heather O.Geotechnical properties of JSC-1A lunar soil simulant[J].Journal of Aerospace Engineering,2010,23(2):111-116.
[26]Perkins S W.Bearing capacity of highly frictional material[J].Geotechnical Testing Journal,1991,18(4):450-462.
[27]张锐,罗刚,薛书亮,等.沙地刚性轮构型仿生设计及牵引性能数值分析[J].农业工程学报,2015,31(3):122-128.Zhang Rui,Luo Gang,Xue Shuliang,et al.Bionic design of configuration of rigid wheel moving on sand and numerical analysis on its traction performance[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2015,31(3):122-128.(in Chinese with English abstract)
[28]林呈祥,钟世英,凌道盛.模拟月壤颗粒形状特征及其对抗剪强度影响分析[J].东北大学学报:自然科学版,2016,37(11):1640-1644.Lin Chengxiang,Zhong Shiying,Ling Daosheng.Analysis of particle shape characteristics of lunar soil simulant and its effect on shear strength[J].Journal of Northeastern University:Natural Science,2016,37(11):1640-1644.(in Chinese with English abstract)
[29]林呈祥,凌道盛,钟世英.模拟月壤抗剪强度试验研究及离散元分析[J].岩土力学,2017,38(3):893-901.Lin Chengxiang,Ling Daosheng,Zhong Shiying.Experimental research and discrete element analysis of shear strength of lunar soil simulants[J].Rock and Soil Mechanics,2017,38(3):893-901.(in Chinese with English abstract)
[30]Knuth M A,Johnson J B,Hopkins M A,et al.Discrete element modeling of a Mars Exploration Rover wheel in granular material[J].Journal of Terramechanics,2012,49(1):27-36.
[31]Johnson J B,Kulchitsky A V,Duvoy P,et al.Discrete element method simulations of Mars Exploration Rover wheel performance[J].Journal of Terramechanics,2015,62(6):31-40.
[32]Jiang Mingjing,Yin Zhenyu,Shen Zhifu.Shear band formation in lunar regolith by discrete element analyses[J].Granular Matter,2016,18(2):32.
[2]叶培建,彭兢.深空探测与我国深空探测展望[J].中国工程科学,2006,8(10):13-18.Ye Peijian,Peng Jing.Deep space exploration and its prospect in China[J].Engineering Science,2006,8(10):13-18.(in Chinese with English abstract)
[3]吴伟仁,于登云.深空探测发展与未来关键技术[J].深空探测学报,2014,1(1):5-17.Wu Weiren,Yu Dengyun.Development of deep space exploration and its future key technologies[J].Journal of Deep Space Exploration,2014,1(1):5-17.(in Chinese with English abstract)
[4]蒋明镜,奚邦禄,申志福,等.月壤水平开挖推剪阻力影响因素离散元数值分析[J].岩土力学,2016,37(1):229-236.Jiang Mingjing,Xi Banglu,Shen Zhifu,et al.Discrete element numerical analysis of factors affecting horizontal pushing resistance in lunar ground excavation[J].Rock and Soil Mechanics,2016,37(1):229-236.(in Chinese with English abstract)
[5]Gao Y,Thomas E D,Pitcher C.Piercing the extraterrestrial surface:integrated robotic drill for planetary exploration[J].IEEE Robotics&Automation Magazine,2015,22(1):45-53.
[6]Tian Ye,Tang Dewei,Deng Zongquan,et al.Drilling power consumption and soil conveying volume performances of lunar sampling auger[J].Chinese Journal of Mechanical Engineering,2015,28(3):451-459.
[7]史晓萌,节德刚,全齐全,等.模拟月壤钻进负载分析与试验研究[J].宇航学报,2015,35(6):648-656.Shi Xiaomeng,Jie Degang,Quan Qiquan,et al.Experimental research on lunar soil simulant drilling load analysis[J].Journal of Astronautics,2015,35(6):648-656.(in Chinese with English abstract)
[8]Taylor L A,Pieters C M,Britt D.Evaluations of lunar regolith simulants[J].Planetary and Space Science,2016,126(7):1-7.
[9]He Chunmei,Zeng Xiangwu,Wilkinson A.Geotechnical properties of GRC-3 lunar simulant[J].Journal of Aerospace Engineering,2011,26(3):528-534.
[10]King R H,Van Susante P,Gefreh M A.Analytical models and laboratory measurements of the soil-tool interaction force to push a narrow tool through JSC-1A lunar simulant and Ottawa sand at different cutting depths[J].Journal of Terramechanics,2011,48(1):85-95.
[11]Allan S,Braunstein J,Baranova I,et al.Computational modeling and experimental microwave processing of JSC-1Alunar simulant[J].Journal of Aerospace Engineering,2012,26(1):143-151.
[12]Suescun Florez E,Roslyakov S,Iskander M,et al.Geotechnical properties of BP-1 lunar regolith simulant[J].Journal of Aerospace Engineering,2014,28(5):04014124.
[13]张宇,余飞,陈善雄,等.CAS-1模拟月壤动剪切模量与阻尼比的试验研究[J].岩土力学,2014,35(1):74-82.Zhang Yu,Yu Fei,Chen Shanxiong,et al.Experimental study of dynamic shear modulus and damping ratio of CAS--1lunar soil simulant[J].Rock and Soil Mechanics,2014,35(1):74-82.(in Chinese with English abstract)
[14]Jiang Mingjing,Li Liqing,Yang Qijun.Experimental investigation on deformation behavior of TJ-1 lunar soil simulant subjected to principal stress rotation[J].Advances in Space Research,2013,52(1):136-146.
[15]Zou Meng,Fan Shichao,Shi Ruiyang,et al.Effect of gravity on the mechanical properties of lunar regolith tested using a low gravity simulation device[J].Journal of Terramechanics,2015,60(4):11-22.
[16]Sture S.A review of geotechnical properties of lunar regolith simulants[M]//Houston:American Society of Civil Engineers.2006.
[17]Arslan H,Batiste S,Sture S.Engineering properties of lunar soil simulant JSC-1A[J].Journal of Aerospace Engineering,2009,23(1):70-83.
[18]蒋明镜,奚邦禄,孙德安,等.TJ-1模拟月壤承载特性物理模型试验研究[J].同济大学学报:自然科学版,2016,44(2):167-172.Jiang Mingjing,Xi Banglu,Sun Dean,et al.Experimental study of bearing behavior of TJ-1 lunar soil simulant using physical model[J].Journal of Tongji University:Natural science2016,44(2):167-172.(in Chinese with English abstract)
[19]邹猛,李建桥,李因武,等.刚性轮-月壤相互作用预测模型及试验研究[J].农业工程学报,2007,23(12):119-123.Zou Meng,Li Jianqiao,Li Yinwu,et al.Prediction model and experimental study on the interaction of rigid-wheel and lunar soil[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2007,23(12):119-123.(in Chinese with English abstract)
[20]黄晗,李建桥,陈百超,等.滑转条件下星球车坡面通过性评估试验[J].农业工程学报,2016,32(16):40-44.Huang Han,Li Jianqiao,Chen Baichao,et al.Experiment of slope trafficability assessment of planetary rover under slip condition[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2016,32(16):40-44.(in Chinese with English abstract)
[21]黄晗,李建桥,吴宝广,等.轻载荷条件下轻型车辆车轮牵引通过性模型的建立与验证[J].农业工程学报,2015,31(12):64-70.Huang Han,Li Jianqiao,Wu Baoguang,et al.Research on lightweight vehicle wheel tractive trafficability model under light load[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2015,31(12):64-70.(in Chinese with English abstract)
[22]Morris R V.Handbook of lunar soils[M].Houston:Northrop Services,Inc.,1983.
[23]林呈祥,凌道盛,钟世英.模拟月壤抗剪强度试验研究及离散元分析[J].岩土力学,2017,38(3):893-901.Lin Chengxiang,Ling Daosheng,Zhong Shiying.Experimental research and discrete element analysis of shear strength of lunar soil simulants[J].Rock and Soil Mechanics,2017,38(3):893-901.(in Chinese with English abstract)
[24]Klosky J L,Sture S,Ko H Y,et al.Geotechnical Behavior of JSC-1 lunar soil simulant[J].Journal of Aerospace Engineering,2000,13(4):133-138.
[25]Zeng X W,Chun M H,Heather O.Geotechnical properties of JSC-1A lunar soil simulant[J].Journal of Aerospace Engineering,2010,23(2):111-116.
[26]Perkins S W.Bearing capacity of highly frictional material[J].Geotechnical Testing Journal,1991,18(4):450-462.
[27]张锐,罗刚,薛书亮,等.沙地刚性轮构型仿生设计及牵引性能数值分析[J].农业工程学报,2015,31(3):122-128.Zhang Rui,Luo Gang,Xue Shuliang,et al.Bionic design of configuration of rigid wheel moving on sand and numerical analysis on its traction performance[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2015,31(3):122-128.(in Chinese with English abstract)
[28]林呈祥,钟世英,凌道盛.模拟月壤颗粒形状特征及其对抗剪强度影响分析[J].东北大学学报:自然科学版,2016,37(11):1640-1644.Lin Chengxiang,Zhong Shiying,Ling Daosheng.Analysis of particle shape characteristics of lunar soil simulant and its effect on shear strength[J].Journal of Northeastern University:Natural Science,2016,37(11):1640-1644.(in Chinese with English abstract)
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