Applied Mechanics and Materials Vols. 423-426

Abstract: Cement silo belonging to special structure, widely used in the cement industry, cement production is essential in the process of building. With the development of society, advances in industrial, cement silo construction have been expanding. This is an update to a cement silo structure, using finite element analysis, calculation and analysis in the context of full and half given mechanical properties, with ANSYS simulation modeling in order to get weak cement silo structure location, and design improvements for the weak position.

Abstract: The input of road roughness, which affects the ride comfort and the handling stability of vehicle, is the main excitation for the running vehicle. The time history of the road roughness was researched with the random phases, based on the stationary power spectrum density of the road roughness determined by the standards. Through the inverse Fourier transform, the random phases can be used to get the road roughness in time domain, together with the amplitude. Then, the time domain simulation of the non-stationary random excitation when the vehicle ran at the changing speed, would also be studied based on the random phases. It is proved that the random road excitation for the vehicle with the changing speed is stationary modulated evolution random excitation, and its power spectrum density is the stationary modulated evolutionary power spectrum density. And the numerical results for the time history of the non-stationary random inputs were also provided. The time history of the non-stationary random road can be used to evaluate the ride comfort of the vehicle which is running at the changing speed.

Abstract: Combining with practical engineering, geometry optimization and engineering applications of transmission tower foundation in the slope is researched by using the finite-difference software FLAC3D. The variation of the pullout, vertical and horizontal ultimate bearing capacity with the diameter and length of the pile is analyzed. And optimization program of actual project is given. Research shows that when the pile length is constant, the variation of the pullout and vertical ultimate bearing capacity is increasing with the diameter increasing significantly and the horizontal ultimate bearing capacity is not significant. When the diameter is constant, the pullout, vertical and horizontal ultimate bearing capacity is increasing with the length increasing significantly. By analyzing nonlinear regression analysis of calculation data, the formula of the ultimate bearing capacity is carried out, which can consider the different pile diameters and lengths. When the gradient and distance of slopes is constant, the pullout, vertical and horizontal ultimate bearing capacity can be carried out with the formula, which can provide a reference to specification revision and engineering.

Abstract: Using 3d finite element method can simulate the process of shield tunnel construction. The paper studies the impact of different tunnel depth on the deformation of soil, when considering different excavation steps in the process of tunnel construction. The results show that the shallower the tunnel depth, and the greater the amount of the surface displacement during the tunnel construction. In the process of the tunnel excavation, the soil surface displacement in front of the shield machine is the result of superposition of the uplift and subsidence. When the tunnel depth increases, the surface displacement curve becomes smoother, and the rate of change becomes slower.

Abstract: Settlement prediction is an important method to judge whether the post-construction settlement of the high-speed railway foundation satisfies the requirement of the standard. The paper uses the numerical calculating method based on creep model to predict the subgrade post-construction settlement of the surcharge preloading processing segment of the high-speed railway through inversing the creep parameters, and does comparative analysis with the more researched function fitting methods. The conclusion is that: (1) the numerical calculating method based on creep model is feasible to predict the post-construction settlement; (2) the method can predict the settlement trend with any time starting point; (3) the method can predict the settlement with relatively less actually measured data so as to saving project cycle.

Abstract: With heavy stress concentration, the fatigue of cable-girder anchorage is one of the most important issues to be considered for the design of long-span cable-stayed bridges. The cable-girder anchorage of the Sutong Bridge taken as subject investigated, the design of experiment model, the determination of fatigue load range and the mechanical features of main components are investigated. The fatigue safety of the cable-girder anchorage in design life and limit life are verified by model test. The results indicate that the accurate simulation of mechanical characteristics and boundary condition of the actual structure can be achieved by the triangular design scheme of the model test with vertical column. The load transfer mechanism of main components of cable-girder anchorage differs notably. The stress concentrations in web plates and bottom plates are predominant. Overall, Sutong Bridge cable-girder anchorage is a reasonable design, and fatigue performance can meet with the design requirements.

Abstract: Wind pressure of pedestrian bridge induced by main line train has been investigated using numerical simulation. Based on time-filtered Reynolds Averaged Navier-Stokes equations, meanwhile, the RNG k-ε turbulent model is selected to close the equations, the three-dimensional incompressible unsteady flow computational fluid dynamics model have been established by commercial software FLUENT. The distribution of wind pressure and the time histories of wind pressure on surface of the bottom of bridge are obtained, moreover, the characteristics of variation process are summarized.

Abstract: Porous material has a function of sound absorption, dense hard material can prevent the spread of airborne sound. The building envelope which is made up of different properties of materials, with good effects on sound insulation, sound absorption and noise elimination, can be widely used in noise control engineering.

Abstract: Aimed at the cement slurry leak problem in the leakiness area cementing of Jilin oilfield, the fiber cement slurry system was developed. The general performance of fiber cement slurry, such as the pressure strength, thickness time, filter loss, flowing ability and water separate rate, etc was analysis in the room condition. The preventing and block leak ability was evaluated. The room and field tests prove that the ability of the fiber cement slurry is best. It can make the field cementing requirement in the leakiness formation and has the best effect of preventing and block leak ability.

Abstract: In this paper, the vibration performance of hybrid sandwich composites plates with different stacking was investigated by modal test. The results showed that the reduction in layer numbers of the unidirectional carbon fiber epoxy prepreg in 0^o direction will result the decrease in the natural frequency values for bending modal, the increment of layer numbers of 2D woven epoxy prepreg with plain weave will result the enhancement the of torsional modal. The reinforcements of unidirectional carbon fiber epoxy prepreg in ±45 ^o direction has a preferential effect on the torsional modal natural frequency of the plate than that of 2D woven epoxy carbon prepreg with plain weave in 0^o direction.