The strength of the contact surface should be divided into stages from the stable state to the final sliding state, as listed in Table 6. (Washington Post photo by Bonnie Jo Mount). The comparison shows that both have four different degrees of cracks, with identical curve trend and characteristics. This is particularly true against a backdrop of dramatically changing temperatures, vegetation and sea level rises in the Reserve and across the Arctic. used the three-dimensional rapid Lagrangian analysis program (FLAC3D, 4.0) of geotechnical engineering to numerically simulate the deformation and failure process of the bank slope rock and obtained the deformation mechanism of the E20 bank slope [27]. The new plan most notably opens the entire Teshekpuk Lake Special Area to oil and gas leasing. The axial force of the NPR anchor cable increases from 400 kN to 530 kN, and its elongation reaches 0.3 m. The sliding distance is 0.6 m. Stage 2 (revival of the old sliding body): with the excavation of the electric shovel, the sliding force of the slope rock mass increases and then the old sliding body revives, the strength of weak sliding surface decreases gradually, and the axial force of the NPR anchor cable increases sharply; the curve of the axial force monitoring increases rapidly to 680 kN, the elongation of the anchor cable reaches 0.64 m, and the relative displacement of sliding surface is 1.54 m. Stage 3 (relative displacement of the 16-1101 slip surface): the slope reached the safety threshold because of shovel excavation. Numerical simulation analysis of the old landslide (Figure. Kai Zhang, 1,2 Xiaojie Yang, 1,2 Xuebin Cui, 1,2 Yong Wang, 1,2 and Zhigang Tao 1,2. Y. Li, S. Zhang, and X. Zhang, “Classification and fractal characteristics of coal rock fragments under uniaxial cyclic loading conditions,”, Z. Qin, H. Fu, and X. Chen, “A study on altered granite meso-damage mechanisms due to water invasion-water loss cycles,”, J. Wang, S.-c. Li, L.-p. Li, P. Lin, Z.-h. Xu, and C.-l. Gao, “Attribute recognition model for risk assessment of water inrush,”, S. Zhang, Y. Li, B. Shen, X.
Based on the monitoring data and the engineering geological conditions of “2016-1101 landslide,” in this study, we established the NPR anchor cable numerical calculation model and carried out numerical simulation on the monitoring of “2016-1101 landslide” through the Fish language in FLAC3D and 3DEC software. 2019C03104) and the Fundamental Research Funds for the Central Universities, SCUT (No. The geological structure in the mining is the fold structure and fault structure dominated by the inverted anticline (the inverted dome structure of the Heibeishan mountain, the inverted anticline of the open-pit mine, and the F1 fault structure). (2)Negative Poisson’s ratio effect of the constant resistance large deformation anchor cable structure. The new plan put forth by the Trump administration adopts a “preferred alternative E” which was not proposed or available for public comment during the draft plan and EIS processes. (1)The double-sliding model is shown below (Figure 23).
(c)Observe the strain increment contour of the sliding surface. During the static tension, the axial force of the anchor cable rises to the maximum constant resistance (850 kN) in a short time and then becomes constant at 850 kN, exhibiting a remarkable constant resistance characteristic. (iii)Numerical simulation analysis of “16-1101 landslide”. Data transmission and aggregation in the monitoring area are mainly based on the data transmission topology (Figure 11). Although they successfully monitored and warned of many dangerous landslides, they neither established the NPR anchor cable numerical calculation model and nor carried out the numerical simulation of the whole process of landslide monitoring and early warning. After the appearance of “16-1101 landslide,” the old landslide body “resurrected” and then slipped, and the 502 m step appeared staggered. The cable structure with a constant resistance and large deformation under axial elongation also undergoes radial structural expansion. The numerical simulation monitoring curve of the anchor cable force shows four times of rise and one time of decline, coinciding with the field monitoring curve. There are microcracks in the rock mass. Stage 4 (16-1101 landslide facing slip warning): the sliding surface completely losses its stability and sends out early warning information. According to these three principles, the maximum displacement of the old landslide after stabilization is ∼1.3 m. The landslide body is basically located at the set position of the contact surface of the model. 1 State Key Laboratory for Geomechanics & Deep Underground Engineering, China University of Mining & Technology, Beijing 100083, China. Static tensile test curve of the anchor cable. (3)After the slope slides (Figure 12(c)): controlling the sliding body In the case of large deformation, the elastic energy is released, the deformation energy inside the slope is less than the design constant resistance P of the resistor, the axial force F of the anchor cable is less than the friction force, and the soil body reaches a new equilibrium and stable state. Caribou and geese at Teshekpuk Lake in North Slope Borough, Alaska, on May 26, 2019. The numerical simulation calculation of the whole process monitoring and early warning target of 16-1101 landslide in Nanfen open-pit iron mine was realized, indicating that the model can be used in Nanfen open-pit mine.
The NPR anchor reinforcement unit is generally defined by geometric parameters, material parameters, and anchorage agent characteristics. © 2020 Anchorage Daily News.
The comparison between the numerical simulation results and the field measurement results shows good agreement between the simulation monitoring curve and the field monitoring curve and proves that this model can be used to monitor the landslide model of Nanfen open-pit mine. The initial average diameters before and after the test in the 2-2 direction are 121.50 and ∼125.66 mm, respectively. Comparison of numerical simulation curve and monitoring curve. The results of this study indicate that the stress monitoring curves and failure characteristics of the NPR anchor cables in the whole process of landslide by the two numerical simulation methods are basically consistent with the field measurement results, providing a theoretical and practical basis for the mechanistic analysis and numerical simulation of other similar slopes. (ii)Numerical simulation analysis of “16-1101 landslide” (Figure 19). Rainfall mainly concentrates in the summer. Stage 2 (old sliding body revival): with the excavation of the electric shovel, the sliding force of the slope increases, the old sliding body revives, the strength of the weak interlayer of the sliding surface decreases gradually, and the axial force of the NPR anchor cable increases sharply; however, the sliding surface does not produce relative displacement. (1) Analysis of the Simulation Results(i)The Mohr–Coulomb elastic-plastic model was used to observe the displacement contours of the slip surface, settlement curve, and NPR cable axial force curve.
When the slope slides, the strength of the contact surface is set as the actual strength of the sliding surface and then slides until reaching the stable state.
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Most of the acreage not available for oil and gas leasing is in the Utukok Uplands Special Area, a remote area of low oil and gas potential. Caribou, waterfowl, shorebirds and other wildlife are dependent on specific undeveloped habitats that have been protected under the 2013 plan. (2)The initial average diameters before and after the test in the 2-2 direction are 121.50 and ∼125.66 mm, respectively. 16-1101 landslide instability displacement contour. Numerical simulation analysis of “16-1101 landslide” (Figure. Wildlife in the Reserve require large areas for their health and survival as their ranges and habitats are dynamic, varying with conditions year-to-year. The landslide body is basically located at the set position of the contact surface of the model.
The authors declare that they have no conflicts of interest. When the calculation exceeds 10,000 steps and the model is still unstable, the calculation is stopped, and the model is considered to be in a plastic flow state. When the sliding surface passes through, the software determines the sliding surface instability and stops calculation. It would dramatically increase the areas open to oil and gas leasing by seven million acres, as well as the areas allowing surface developments by 4.3 million acres. After the start of “16-1101 landslide,” the axial force variation characteristics of the NPR anchor cable, the elongation variation curve of the anchor cable, the vertical relative displacement curve of monitoring point 1 on the upper edge of the old landslide body, and the vertical relative displacement curve of monitoring point 2 on the upper edge of “16-1101 landslide” are shown in Figure 26. The 2013 plan prohibited leasing in approximately 3.1 million acres surrounding Teshekpuk Lake to protect the calving, migration and insect relief areas required for the Teshekpuk Lake caribou herd — counted at more than 56,000 animals in 2017. The anchor cables are numbered as “MS-01-01,” “MS-01-02,” and “MS-01-03,” and their physical parameters are listed in Table 1. When the sliding surface passes through, the software determines the sliding surface instability and stops calculation.
Figure 3 shows the schematic diagram of the static stretching system. Comparison of simulation results with field conditions. At present, a series of numerical methods such as finite difference method and finite volume method for different types of sliding bodies have been developed. Numerical simulation analysis of “16-1101 landslide”. The comparison between the numerical simulation results and the field measurement results shows good agreement between the simulation monitoring curve and the field monitoring curve and proves that this model can be used to monitor the landslide model of Nanfen open-pit mine. The NPR anchor cable model was constructed by FLAC3D software, as shown in Figure 15. combined C++ programming technology and finite difference method and realized the three-dimensional numerical simulation of slope through the intelligent inversion analysis of the structural parameters of the soil slope [28]. In summary, the large deformation anchor cable with a constant resistance has supernormal tensile properties, NPR characteristics, and constant resistance characteristics.