Advanced Materials Research Vols. 919-921

Abstract: On the basic of rock and soil mass mathematic model, with the boundary conditions of classic section, the seepage field in construction period is simulated. Some conclusions are drawn: the hydraulic gradient of the channel slope where the seepage spills out exceeds the allowable hydraulic gradient and some engineering measures are needed to avoid seepage damage; hydraulic gradient on rock base is less than the allowable hydraulic gradient and the seepage is safe.

Abstract: The security researches of energy dissipation were always the focus in the High arch dams. Statistically, the trajectory type energy dissipation is the most widely used in the built high arch dams, and the protected plunge poor were always set downstream the dam body. However, the widely used protected plunge poor need large investment with the disadvantage of complicated operation and maintenance. Along with the construction of concrete high arch dam in the Southwest China, the “Reventment-Protected and Non-Bottom-Protected Plunge Pool” has been studied and proposed, which has the advantage of more simplified project design and more economy investment.

Abstract: The South-to-North Water Transfer Project is a cross century water diversion project. So it is very important to ensure its normal operation. The hydraulic calculation of Jiping Canal of the South-to-North Water Transfer Project is carried out in this paper, working out cross section, the profile and the X-Y-Z perspective plot of Jiping Canal respectively. An analysis of the canal stability enables us to get the condition in which the canal is stable, which will provide strong technical support for the design and construction of the canal. Therefore, the analysis has important practical significance. The study will be effective guidance on the normal operation of Jiping Canal of South-to-North Water Transfer Project.

Abstract: Based on the analysis of the regional geological and hydrogeologic conditions of a coal mine in Xishan Coalfield, Shanxi Province in China, the groundwater aquifer system is generalized as a three layers structure in vertical direction and a three-dimensional unsteady flow model in confined aquifer is established. The regime of karst groundwater levels under the coal mining conditions for both Carboniferous and Ordovician limestone aquifers are predicted by using Visual Modflow. The results show that the groundwater levels of the two aquifers are all in decline as a result of coal mining. After 2373 days of mining, the maximum drawdown is 137m in Carboniferous limestone aquifer with the unwatering area in southeast, while the water level in Ordovician limestone aquifer dropped by 8.1m. The dropped rates of groundwater levels in the two aquifers trend to decrease with the coal mining. The results play an important role in the reasonable protection of water resources.

Abstract: This paper mainly discusses some details when applying data assimilation method via an ensemble Kalman filter (EnKF) to improve prediction of adsorptive solute Cr(VI) transfer from soil into runoff. Based on this work, we could make better use of our theoretical model to predict adsorptive solute transfer from soil into surface runoff in practice. The results show that the ensemble number of 100 is reasonable, considering assimilation effect and efficiency after selecting its number from 25 to 225 at an interval of 25. While the initial ensemble value makes little difference to data assimilation (DA) results. Besides, DA results could be improved by multiplying an amplification factor to forecast error covariance matrix due to underestimation of forecast error.

Abstract: To study the vibration response of submerged floating tunnel tether under the combined action of vortex-induced vibration and parametric vibration, a non-linear vibration equation based on wake oscillator model is set up taking the geometric nonlinearity of tether into account, in which effect of tube on tether is simplified as axial excitation. An approximate numerical solution of planning submerged floating tunnel tether is obtained by applying Galerkin method and Runge-kutta method. The variation degree of mid-span displacement response and axial force of tether is analyzed when the vortex-induced resonance and parametric resonance occur. The results show that, when vortex-induced resonance and parametric resonance occur simultaneously, the mid-span displacement and axial force of tether increase dramatically; the tether sag effect results in the asymmetry of tether mid-span vibration amplitude.

Abstract: In order to improve the management of groundwater by the groundwater level, this paper selects the ErLongtao irrigation area, Tailai County of Heilongjiang Province as an example, is based on the principles that without the occurrence of geological hazards, does not destroy the ecological environment and does not affect the normal production. Considering the example area actual situation, this paper constructs example of groundwater key groundwater level index, and delineates the groundwater key groundwater depth.

Abstract: In this paper, a three-dimensional beam element is developed for geometric nonlinear dynamical analysis. This element is based on the co-rotational formulation, in which the displacements of beam element are subdivided into rigid body movements and elastic deformations. The formulations are derived from the continuum mechanics based Updated Lagrangian incremental equations. The element can undergo large deflections and rotations, but small strains are assumed in the deduction. The validity of this element is confirmed by comparing with the numerical results in other literatures.

Abstract: A quantum mechanics study on the electronic properties and copper activation of Fe- and Cd-bearing sphalerite (ZnS) has been done using density-functional theory (DFT). Calculated results indicate that Fe impurity introduces the impurity state near the Fermi level and Fe-S bond shows stronger covalent character. Moreover, Fe impurity could not be replaced by Cu atom due to the more stable electronic structure, which results in the reduced copper adsorption amount. For the Cd-bearing ZnS, the Cd-Zn substitution introduces large lattice distortion and the Cd-S bond shows stronger ionic bonding character than Zn-S bond. For Cd-bearing sphalerite, Cd atom is easily replaced by Cu atom, which could increase the Cu²⁺ adsorption. The experiments of copper adsorption on the synthesized Fe-doped and Cd-doped ZnS samples confirm the simulation prediction.

Abstract: In this paper, an algorithm for computing logarithms of r-sum of first and last circulant matrices is given.