The strength and failure characteristics of most natural rock mass are influenced by discontinues such as fissures, joints, and weak surfaces. In the present study, the strength and failure behavior of ubiquitous- joi...The strength and failure characteristics of most natural rock mass are influenced by discontinues such as fissures, joints, and weak surfaces. In the present study, the strength and failure behavior of ubiquitous- joint rock-l!ke specimens under uniaxial loading have been investigated by DIC （digital image correlation） and discrete element numerical method （PFC2D）. The results are obtained. Firstly, the UCSJ of spec- imens with γ= 15° or 30° shows similar tendency while α goes from 0° to 75°. With γ= 45° or 60°, the UCSJ of specimens increases when α goes from 0° to 30° and decreases after α goes beyond 30°. With γ=75°, the peak UCSJ value is reached when α=0°. The UCSJ value shows an increasing trend when α goes from 60° to 75°. Secondly, the ubiquitous-joint specimens present different failure modes for various levels of α and γ（β-α）. Based on the experimental results, the failure mode of ubiquitous-joint specimens can be classified into three categories： stepped path failure, failure through parallel plane, and failure through cross plane.展开更多
The results of a study on the binary HIP 18856 and construction of its orbit are presented.New observational data were obtained at the BTA of SAO RAS in 2007-2019.Earlier,Cvetkovic et al.constructed the orbit for this...The results of a study on the binary HIP 18856 and construction of its orbit are presented.New observational data were obtained at the BTA of SAO RAS in 2007-2019.Earlier,Cvetkovic et al.constructed the orbit for this system.However,it is based on six measurements,which cover a small part of the orbit.The positional parameters of the ESA astrometric satellite Hipparcos published speckle interferometric data(Mason et al.,Balega et al.,Horch et al.)and new ones were used in this study.Based on the new orbital parameters,the mass sum was calculated and the physical parameters of the components were found.The obtained orbital and fundamental parameters were compared with the data from the study by Cvetkovic et al..The comparison shows that the new orbital solution is better than the old one,since it fits new observational data accurately.Also based on a qualitative evaluation performed by Worley&Heintz,the new orbit was classified as"reliable",which means data cover more than half of the orbit with sufficient quantities of residuals of measurements.展开更多
基金funding from Project (Nos.51474249 and 51404179) supported by National Natural Science Foundation of ChinaProject Supported by Innovation Driven Plan of Central South University of China (No.2016CX019)Project (No. SKLGDUEK1405) funded by the Open Projects of State Key Laboratory for Geo-mechanics and Deep Underground Engineering of China University of Mining and Technology,in China
文摘The strength and failure characteristics of most natural rock mass are influenced by discontinues such as fissures, joints, and weak surfaces. In the present study, the strength and failure behavior of ubiquitous- joint rock-l!ke specimens under uniaxial loading have been investigated by DIC （digital image correlation） and discrete element numerical method （PFC2D）. The results are obtained. Firstly, the UCSJ of spec- imens with γ= 15° or 30° shows similar tendency while α goes from 0° to 75°. With γ= 45° or 60°, the UCSJ of specimens increases when α goes from 0° to 30° and decreases after α goes beyond 30°. With γ=75°, the peak UCSJ value is reached when α=0°. The UCSJ value shows an increasing trend when α goes from 60° to 75°. Secondly, the ubiquitous-joint specimens present different failure modes for various levels of α and γ（β-α）. Based on the experimental results, the failure mode of ubiquitous-joint specimens can be classified into three categories： stepped path failure, failure through parallel plane, and failure through cross plane.
基金funded by RFBR,project number 20–32–70120Funding for the DPAC has been provided by national institutions,in particular the institutions participating in the Gaia Multilateral Agreement。
文摘The results of a study on the binary HIP 18856 and construction of its orbit are presented.New observational data were obtained at the BTA of SAO RAS in 2007-2019.Earlier,Cvetkovic et al.constructed the orbit for this system.However,it is based on six measurements,which cover a small part of the orbit.The positional parameters of the ESA astrometric satellite Hipparcos published speckle interferometric data(Mason et al.,Balega et al.,Horch et al.)and new ones were used in this study.Based on the new orbital parameters,the mass sum was calculated and the physical parameters of the components were found.The obtained orbital and fundamental parameters were compared with the data from the study by Cvetkovic et al..The comparison shows that the new orbital solution is better than the old one,since it fits new observational data accurately.Also based on a qualitative evaluation performed by Worley&Heintz,the new orbit was classified as"reliable",which means data cover more than half of the orbit with sufficient quantities of residuals of measurements.
