Papers by Keyword: Slope Angle

Abstract: Rainfall-runoff process plays an important role in hydrological cycle, and the study on the rainfall-runoff will provide foundation and basis for research on basin hydrology and flood forecasting. In this paper, the surface runoff and subsurface flow of wheat were observed in the laboratory by artificial rainfall, and analyzed the cumulated surface runoff and recession process of subsurface flow by regression analysis. In addition, the factors affected the runoff and response of soil moisture on the runoff coefficients was also discussed. Results showed that the rainfall intensity, soil coverage and slope had important influence on the surface runoff generation, and the surface runoff was observed when the total rainfall amount exceeded 32mm and 13mm for 5°and 15° slope respectively. The cumulative surface runoff could be expressed as a power function, which had higher determination coefficient R² (0.92~0.999). The subsurface flow was only observed at the ripening period and wheat stubble treatment, and mainly affected by slope angle and initial soil moisture, whereas rainfall intensity showed little impact. The recession curve of subsurface flow can be described as a simple exponential expression or power function, which the determination coefficient was 0.88 and 0.94 by regression analysis, respectively. Moreover, there was an obvious threshold (approximately 30%) between the average initial soil moisture and runoff coefficients, which the runoff increased significantly as above the threshold.

Abstract: The conventional distance estimation system only uses a constant speed and a constant level of road elevation to estimate the driving mileage for a vehicle. This technique leads to a low accuracy. In the current project, a new estimation technique namely; the Contour Positioning System (CPS) for an electric vehicle has been proposed. The CPS has a better estimation on the electric vehicle battery usage because of the consideration of road elevation, regenerative energy etc. In order to perform the CPS calculation, the elevation profile of the selected destination must be known. In this paper, the technique to extract the elevation profile i.e. latitude, longitude and altitude has been performed and evaluated using Google Maps or Google Earth^Ò. This method enables the user to obtain the road information and compute the amount of energy needed to reach the said destination.

Abstract: There is a vitrified bond CBN point grinding wheel with coarse grinding area slope angle θ. This new grinding wheel has higher removing rate and better machining accuracy than conventional wheels. The design and manufacture principle of the new grinding wheels are studied in this paper. These wheels with different coarse grinding area slope angle θ are used to grind the stepped shaft of QT700 with a series of grinding parameters.VHX-1000E microscopic system and Micromeasure system are used to measure the surface quality of workpiece. In the same group of grinding parameters, compare the effect of these different wheels on surface roughness. The effect of deflection angle α on surface roughness is generalized.

Abstract: The critical slip field theory is applied to optimization design of the slope angle. An intelligent matching optimization of the slope angle design is carried out based on the strata distribution, mechanics parameters of rock mass and a given security reserve. That is the implementation of the maximum allowable slope angle of slope rock mass under the given conditions. Optimized by the final highwall of Buzhaoba Open-Pit Mine, the overall slope angle increased 3°compared to the original design. Which implement the optimum slope angle of final highwall, modified the shortcoming in the original design and ensure the maximization of mine safety and the resource exploitation.

Abstract: As there is a few area or topographic factors for landfill site, the slope angle becomes steeper because it makes much disposal capacity. Tensile force in the geotextile is caused by compaction work of disposed waste, and the tensile force is transferred into the liner system by friction, but the tensile force of liner system will change with a change of slope angle, so it is very important to determine the amount of tensile forces creating at the fixed ends of liner system for avoiding the tearing failure of liner system and designing the anchorage. In this paper, FEM analyses, in which the joint element was used to model the interface between the liner system, were conducted to estimate the tensile forces creating at the fixed ends of liner system with a change of slope angle from 1:2.5 to 1:0.2. The analysis results show that the tensile forces creating at the fixed end of liner decrease as the slope angle increases.

Abstract: In the process of tunnel excavation, due to the complexity of geological and geomorphic conditions etc, in the given tunnel heading shape conditions, it is more important to determine the tunnel location near tunnel portal. The large-scale finite numerical simulation software ANSYS is adopted to analyze that stress and displacement of tunnel surrounding rock vary with unsymmetrical location, including burial depth, slope angle and thickness of overburden layer. The analysis results show that: Under the condition of reinforcement in advance, it is proper for the tunnel excavation to reduce burial depth and thickness of overburden layer. This paper provides the theory basis for rational selection of support types and parameters and proper determination of tunnel location.

Abstract: Geocell protection of slope was influenced by environment and climates largely. Many of them came to failure when subjected to rainfall infiltration. Aiming at the general shear failure mode of the geocell-protection-system (GPS), its stability analysis model during rainfall was established by the limit equilibrium method. A new approach of evaluating stability of the GPS was proposed.

Abstract: Inbetween the many factors, which will influence the distribution character of initial stress in a mountain, different angle of mountain slopes and horizontal geostress will have important effects on it. Therefore, stress distribution in mountains under different slope angles with considering different lateral coefficients of initial stress is studied using numerical method in here. In this paper, the initial geostress distribution of mountain at typical vertical profiles are studied in the gravity field, with the slope angles being 30°, 45° and 60°, respectively. After the calculation, it can be known that the actual initial vertical stresses may be 2-5 times of the gravitational stresses calculated by direct depth gh for some zones. Meanwhile, it reveals that different horizontal geostress has a momentous impact on it as well. Computation of damage-fracture model for jointed rock is adopted to analyze the rock stability of a cavern. Comparison of the rock stability excavated in a mountain area or under a flat surface is made also.

Abstract: As there is a few area or topographic factors for landfill site, the slope angle becomes steeper because it makes much disposal capacity. Tensile force in the geotextile is caused by compaction work of disposed waste, and the tensile force is transferred into the liner system by friction, but the tensile force of liner system will change with a change of slope angle, so it is very important to determine the amount of tensile forces creating at the fixed ends of liner system for avoiding the tearing failure of liner system and designing the anchorage. In this paper, FEM analyses, in which the joint element was used to model the interface between the liner system, were conducted to estimate the tensile forces creating at the fixed ends of liner system with a change of slope angle from 1:2.5 to 1:0.2. The analysis results show that the tensile forces creating at the fixed end of liner decrease as the slope angle increases.

Abstract: Rock slope failure mechanisms were assessed in this study using KOPEC and RCC quarries as case studies in Oyo state. Discontinuities such as joints and bedding planes were obtained through face mapping and scanline survey of the excavated slopes of the quarries. Stereographic projections of the discontinuities were generated using ROCKPACK III and the stereonets analyzed in accordance with Markland’s plane failure analysis. The results of the analyses show that there are possibilities of plane failures in the south- east region of KOPEC quarry slope face and south –west region of RCC quarry slope face. It is therefore recommended that constant monitoring of the slope failure should be done and the slope angle should be less than 700 and 600 for KOPEC quarry and RCC quarry respectively.