Applied Mechanics and Materials Vols. 580-583

Abstract: In Diaobingshan area, Use 76 data points (geodetic height and normal height are known) as experimental data, the quadric surface fitting mean square error as GPS height partition fitting basis in the area. In 76 data points, some data points which GPS height fitting residual value is less than the quadric surface fitting mean square error in a region, other points which GPS height fitting residual value is more than the quadric surface fitting mean square error in a region, in the same time, individual regions (data points is less) use mobile triangle method to establish GPS height the fitting model. The experiment prove that the effect of this kind partition fitting method is better than that of no partition fitting method, has a certain reference value.

Abstract: The super open-caisson foundation of Taizhou Yangtze River Bridge was used by positioning system of anchor piers. GPS RTK Techniques was used to real-time monitor the open-caisson and by software compute current geometric posture of open-caisson timely. This could provide guarantee for sinking of caisson, and shorten construction period and save cost.

Abstract: An algorithm for triangle interpolation on discrete points is presented in the paper. It creates a square mesh which covers all the discrete points, then puts the points into the mesh and records the relationship between grids and points. When interpolating elevation of an interpolation point, it can fast find the discrete points which are near the interpolation point and these discrete points can be used to create a special triangle which contains the interpolation point. The elevation of the interpolation point can be obtained from the triangle. The method has the advantage of fast speed, high precision and needing less memory.

Abstract: Effect of ring support position and geometrical dimension on the free vibration of ring-stiffened cylindrical shells is studied in this paper. The study is carried out by using Sanders shell theory. Based on the Rayleigh-Ritz method, the shell eigenvalue governing equation is derived. The present analysis is validated by comparing results with those in the literature. The vibration characteristics are obtained investigating two different boundary conditions with simply supported-simply supported and clamped-free as the examples. Key Words: Ring-stiffened cylindrical shell; Free vibration; Rayleigh-Ritz method.

Abstract: The simulation of two-phase oil-water coupling flows in a low permeability reservoir with capillary pressure and start-up pressure gradient was carried out. First of all, the state equations with all the oil pressures at grid nodes were established based on lump-centre finite difference method. Secondly, the recurrence formulae of all the oil pressures and water saturations at grid nodes were built up according to IDPIM and an explicit difference method, respectively. Finally, the simulation of two-phase oil-water coupling flows for a typical five point area water injection as an example was carried out. Simulating results show that capillary pressure has a little effect on moisture rate and oil production, but startup pressure gradients have an outstanding effect on them. Therefore the existence of startup pressure gradients will enhance the difficulty of oil development.

Abstract: In this paper, the vertical vibration influence on the surface velocity of a 5cSt silicone oil liquid bridge has been investigated numerically. The Navier-Stokes equations coupled with the energy conservation equation are solved on a staggered grid, and the two-phase surface is captured by using the mass conserving level set method. The present results indicate that the axial and radial surface velocities of the liquid bridge are suppressed by the external vertical vibration.

Abstract: A linearization method of the uniaxial non-fitting nonlinear stress-strain curve given by the author of the paper is presented. The evolution equation between disturbances variable and plastic strain is derived based on Theory of Duality Disturbance. A simple method for concrete structures preforming elastoplastic analysis is presented (including softening analysis).

Abstract: The distinctive paper is devoted to general principles of mesh approximation for boundary problems of structural analysis with the use of so-called method of extended domain, proposed by Prof. Alexander B. Zolotov. In particular we studied questions dealing with approximation of domain, approximation of functions and approximations of operators. Mesh functions are introduced as well as corresponding mesh operations and various types of implementation. The results are rather efficient algorithms in respect to number of operations, computing time and required memory.

Abstract: Models with main-branch channel, crossing channel and net type channel are established and nutrient liquid with a velocity of 0.01m/s is adopted in the study to investigate the fluid field in the channel by using FEA software FLUENT. The velocity and pressure distribution have been obtained in the investigation. By comparing the results in the three models, pressure and velocity distribution in the second and the third models are relatively uniform and are appropriate for the bionics principles. Studies in this paper will be of benefits for the development of tissue engineering.

Abstract: The general parallel preconditioning subspace iteration software GPPS is developed based on the integration of various preconditioning methods, parallelization techniques, and subspace iterations, to solve general sparse linear systems. The software has several characteristics, including high computational performance, good readability, simple interface, and excellent scalability. In this paper, the functions of the software are outlined, and then it is used to solve the sparse linear systems from meso-scale simulation of concrete specimens. The numerical experiments show that GPPS is clearly superior to the software package AZTEC, which is used in the simulation up to now, and in addition, ICT and the parallelization technique based on factors combination outperform other preconditioning techniques integrated in the software.