Applied Mechanics and Materials Vols. 353-356

Abstract: A nonlinear dynamic model for non-planar vibration of inclined cable with three lumped masses was developed by Hamilton principle, which considered the influence of the lumped masses, the external excitation and the inclination angle of the cable. The partial differential equations of this system were discretized to four degree of freedom ordinary differential equations by Galerkin method. The results show that there were complex model coupling between in-planar and out-planar model, first and second order model in this nonlinear dynamic system.

Abstract: In this paper a kind of quasi-linear singular perturbed problems with infinite initial conditions is investigated. The existence and uniqueness of the solution are proved.Therefore the asymptotic analysis of the solution can be obtained.

Abstract: A numerical triaxial apparatus based on discrete element method is developed on the platform of Yade using Python script. A DEM model with rolling resistance contact considered is proposed for dense granular materials, which is then applied in triaxial compression test of Chende sand. Stress-strain response and volume-axial strain response of the DEM model agree well with that of experiments, with a good prediction of dilatancy angle. Degradation of granular materials duo to particle erosion is also investigated using triaxial compression tests. It is indicated that peak friction angle decreases with the remove of particles if strong force network of granular materials is destroyed.

Abstract: In order to analysis thermal stress of mass concrete accurately, material properties of mass concrete are studied by numerical simulation method, and the equivalent age is introduced to describe the mechanical properties of concrete. The calculation models of concrete mechanical parameters are summarized, and then the calculation procedures are established on the basis of equivalent age. In this way, the temperature and temperature history are considered in these models. Meanwhile, the governing equation and computer program of the thermal stress based on the equivalent age are developed. The comparison of the numerical example using proposed method and conventional FEM method shows that the proposed method performs more adaptable and accurate.

Abstract: Several existing interface relaxation methods for finite element–boundary element coupling (FEM–BEM) and for boundary element–domain decomposition (BEM–DD) are reviewed. Furthermore, an interface relaxation method for BEM–DD is presented. This is Part I of two papers. In Part II, the convergence conditions of the interface relaxation FEM-BEM coupling and BEM-DD method are established. Example application is given for elaboration

Abstract: In Part I of this paper, a mixed Dirichlet-Neumann interface relaxation method for boundary element–domain decomposition (BEM–DD) is presented. In this part, the convergence conditions of the mixed Dirichlet-Neumann interface relaxation finite element-boundary element coupling (FEM–BEM) and for BEM–DD method are established.

Abstract: The finite element model of the combination bracket about solar collector was built and modal characteristics of the structure were analyzed. Wind speed time series was simulated in a given wind speed of the wind power spectrum by AR mode of linear filtering and fluctuating wind load time samples were got in each node on the windward side. The curve of load time series was took as the power input, and the wind-induced response of structures was calculated under random wind loads by the transient analysis. The results show that the large displacements appears on the edge of Collector components along horizontal and vertical direction in the case of fluctuating wind and the greater stress occurs in the joint of the cantilevered brackets connect and the upper end of the torque box, so it should be noted in the design of brackets of solar collector.

Abstract: Although installing offshore pipelines by reel-laying method is eases and cost-effective, still conceal some of plastic deformation into the pipeline which may, in combination with ageing, affect strength and ductility of the pipe material. Therefore, reeling pipelines that internally pressurized is addressed in this study sifting parametrically pipelines stiffness to prevent the ovalization and bifurcation produces during spooling of (initially straight) or laying of (initially bent) pipe. A combination of composite materials is examined and number of bending cases at the limit of ovalization and bifurcation is investigated. It is demonstrated that composite pipeline exhibit more bending stability than Steel. Results on the strain energy release in the reel lay system are presented, extending the findings of previous works on the methods of spooling and laying mechanism.

Abstract: This paper summarized the research method of flexible multi-body system dynamics. Three stages of flexible multi-body system model are reviewed. The paper is especially summary on modeling method of flexible multi-body system, flexible multi-body dynamical equation numerical calculation and flexible multi-body system vibration control and so on. And the paper is looked forward to further study.

Abstract: The bridge vibration problem would be highlighted due to flexibility of bridge when traffic is run on the long-span & high-tower continuous rigid-frame bridge. The finite-element (FE) software of bridge-vehicles coupling vibration theory was utilized to analyze traffic load influence on bridge vibration. It is found that the vehicle accelerations are varied greatly in the middle of mid-span and edge of side-span and vehicle bodies are plunged. According to the evaluating indicator of comfort level, people feel sea-sickness when vehicles run in design speed with fundamental frequency. Due to fundamental frequency of body in different speed, the sea-sickness feel will be stronger with lower speed. The impact action can be decreased by the increase number of vehicle-line load, and it is affected by the distance of vehicle-line load.