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In order to study the evolution characteristics of the fracture plane of the anti-dip rock slope with the steep and gently dipping structural plane under the condition of its own weight. Taking the toppling deformation form of right abutment of Miaowei Hydropower Station as the geological prototype, the centrifugal model test was carried out by presetting non-penetrating cracks of the rock strata in different parts of the slope body to simulate the evolution characteristics of the fracture surface of the anti-dip rock slope under the condition of its own weight. The researches have demonstrated that: (1) The failure of anti-dip rock slopes with steep and gently dipping structural planes are marked by the formation of fracture surfaces, which are divided into three stages: in the initial period (0–40g, g is the acceleration of gravity), it refers to the stage of partial fracturation which takes partial fracturation and stratum forwarding on the trailing edge as the major failure characteristics with less position changes in slope plane. In the middle period (40g–80g), it refers to the formation stage of major fracture plane which can be formed in the deep structural plane of slope through expansion and connection in a top-down approach. Position changes in slope nearly account for 3/4 of total position changes. In the later period (80g–120g), it refers to the formation stage of multi-stage fracture plane whose main formation feature is the stress redistribution of fracture strata within the slope. Position changes in slope basically remain unchanged. (2) The fracture of rock bridge between structural planes is transient, but the formation of fracture plane is a gradual development process which is mainly controlled by steep-inclined structural planes. The strain at the crevice of the main fracture plane is the greatest and the stress mode is the most complex. And the fracture strain at the secondary fracture plane takes the second place. Based on fracture mechanics, the fracture criteria of the rock compression-shear and unbalanced force formula for rock stratum have been simplified. It is revealed that the unbalanced force of the rock stratum at the main fracture surface decreases from 1/3 of the slope height to the bottom and top of the slope. The formation of fracture surface is mainly affected by the ratio of the intensity factor of shear stress to normal stress, the length of rock structure plane and the crack rate.

Totally asymmetric exclusion processes at constrained m-input n-output junction points under random update are studied by theoretical calculation and computer simulation in this paper. At the junction points, the hopping rate of particles from m-input parallel lattices to n-output parallel lattices is assumed to be equal to r/n (0c = n(1 √ - 1 m/n)/m. In the cases of r > rc and r < rc, qualitatively different phases exist in the system. With the increase of the value of m/n, the regions of (LD, LD) and (MC, LD) or (HD, LD) decrease, and the (HD, HD) is the only phase that increases in the region (LD stands for low density, HD stands for high density, and MC for maximal current). Stationary current and density profiles are calculated, showing that they are in good agreement with Monte Carlo simulations. [ABSTRACT FROM AUTHOR]

To investigate the correlation between carbon and oxygen isotope compositions of plant cellulose and climatic factors as well as plant physiological indices on the southeastern margin of the Qinghai-Tibet Plateau, we examined plant species in eight sampling sites with similar latitudes and different longitudes in this region. Through the characteristics of δ 13 C and δ 18 O values, fractionation values (Δ 13 C and Δ 18 O) in leaf cellulose, we discussed water use efficiency (WUE) and the environmental factors, the variation of carbon and oxygen isotopes in the southeastern margin of the Qinghai-Tibet Plateau with elevation and longitude, and revealed the indication degrees of isotopic signals to different environments and vegetation physiology. By using the semi-quantitative model of carbon and oxygen dual isotopes, we investigated the physiological adaptation mechanisms of plants to varying environmental conditions. The results demonstrated that both Δ 13 C and Δ 18 O of cellulose decreased with increasing elevation and longitude, and Δ 13 C was more influenced by longitude, while Δ 18 O was more susceptible to elevation variation. Additionally, Δ 13 C and Δ 18 O were significantly and positively correlated with temperature (TEM), precipitation (PRE), potential evapotranspiration (PET), and relative humidity (RH). PRE was the dominant meteorological factor driving the variation of Δ 13 C, while RH was the dominant meteorological factor influencing Δ 18 O variation. In contrast to Δ 13 C, WUE showed a stronger correlation with elevation than with longitude, which increased as elevation and longitude increased. According to the carbon-oxygen model, plant stomatal conductance ( g s ) and photosynthetic capacity ( A max ) decreased with increasing precipitation and relative humidity, while the values increased with increasing elevation and longitude. The combined analysis of carbon and oxygen isotopes of organic matters would yield additional environmental and gas exchange information for studies on climate tracing and vegetation physiology studies on the southeastern margin of the Qinghai-Tibet Plateau.