Advanced Materials Research Vols. 243-249

Abstract: This article is probed into on the issue that the influence of border concealed column toward shear wall stiffness. Charge example indicates finite element that this text set up calculate model is acceptable. It is used the finite element method basic theory to compile finite element analysis procedure with four points rectangles unit to solve this problem. It can calculate the shear wall with concealed column’s displacement under the wind load to check the result it whether can be satisfied the design request. Using this procedure, this article carries on the finite element modeling analysis on a ten-floor building shear wall structure system. The procedure’s result and the software of ANSYS’s result tallies well, and it also be compared with the simplification computation’s result.

Abstract: The stiffened plate with rids was considered as a whole structure. Using energy method the stability of stiffened plates with rids under the longitudinal forces was analyzed. Calculating the potential energy of deformation of plate and that of rids and the work done by the neutral plane forces of plate when the plates were buckled, the formulas of critical loads of the stiffened plate with rids under longitudinal forces were derived from the minimum condition of total potential energy. Using the formulas in this paper engineers can easily calculate the critical loads of the stiffened plate with rids under the boundary conditions: the opposite sides are fixed and the other opposite sides are simply supported, four sides are simply supported. The formula of critical loads of the stiffened plate with rids under other boundary conditions can be derived using the method in this paper.

Abstract: The generalized differential-matrix equations of transverse vibration of the beams were set up and they were solved by means of Cauchy sequence iterative method. Then according to the boundary conditions at two ends of the beams the natural frequencies of the transverse vibration of the different beams including the complex beams of non-uniform section and composite beams under different boundary conditions were figured out. The form of the differential-matrix is simple. The calculation of the sequence iterations can be accomplished by simple computer program. Using the method in this paper, the amount of work of calculation is reduced greatly and the results are accurate compared with the approximate method in which a beam of non-uniform section is replaced by many small segments of equal cross-section.

Abstract: We discussed the problems of dynamic stability of cuneiform pile under vertical dynamic load, and studied the influence of parameters resonance and soil resisting force on dynamic stability of foundation pile.

Abstract: Utilizing general finite element software ANSYS, the finite element computing model of the steel spatial tubular joint is built, which is used to analyze the mechanical properties under dead loads through changing its design parameters. According to the obtained and compared consequences, the different design parameters including stiffening ring thickness, cross-shaped ribbed plate thickness and stiffening ring length exert different influence on ultimate bearing capacity of the steel spatial tubular joint. Specifically, the ultimate bearing capacity under dead loads is affected by setting stiffening ring and changing cross-shaped ribbed plate thickness significantly. In contrast, if the thickness and length of stiffening ring are changed, the impact is insignificant. The results and conclusion can provide reference which is useful to optimize the design of steel spatial tubular joint in such category.

Abstract: The stability of the cracked visoelastic rectangular plate of varying thickness subjected to uniformly distributed tangential follower force is investigated. Two models describing thickness variation are parabolic and linear variations along one edge of the plate. This is done in order to show how critical loads for cracked visoelastic thin plate subjected to follower force can be obtained using the two-dimensional viscoelastic differential constitutive relation and the thin-plate theory. The differential equations in the Laplace domain are established. The complex eigen-value equations are derived by the differential quadrature method. The generalized eigen-value under different boundary conditions is calculated. The effects of the plate parameters, the crack parameters and the dimensionless delay time on the stability of the viscoelastic plates are analyzed. The crack is found to change the type of instability and reduce the stability of varying thickness viscoelastic plate.

Abstract: To study the influence of steel strands corrosion on the bond behavior for anchoring of pre-tensioned prestressed concrete beams, nine specimens were fabricated. Of which, 5 beams were mixed with salt and set in different places to be corroded in different intensity for 13 months. Then the load test was held to all the 9 specimens and the load-slip curves were obtained. The results show that under the condition of no corrosion crack, the short-term anchoring bond strength of pre-tensioned prestressed concrete beams increases for the steel strands corrosion. Because the tension behavior of steel strands deteriorates remarkably even if the corrosion is slight, which is the dominant cause for the degradation of fundamental structural behavior, the influence of steel strands corrosion on the bond behavior for anchoring may be ignored.

Abstract: The vertical distance is generally greater of long-span cable-stayed bridge, while the velocity of seismic wave propagation is certain, therefore, the incentive suffered of long-span cable-stayed bridge’s pier is not the same time, but there is a certain time interval. Currently in the bridge designs, seismic response analysis is numerically based on coincident earthquake excitation, so that the actual results are different from the results of obtained widely. Based on the analysis of the traveling wave effect to the long-span cable-stayed bridge under the assumption of seismic waves, there are a series results of the bridge control point displacement, the maximum internal force of the earthquake response, and through these results, conclude some effective conclusions.

Abstract: In this paper, an elastic plastic damage model is presented based on the combined use of elastic plastic constitutive equations along with continuum damage mechanics. A tensile and a compressive damage variable are adopted to describe the different responses of concrete under tension and compression, respectively. The Helmholtz Free Energy is decomposed into hydrostatic stress component and deviatoric stress components. The hydrostatic stress component is neglected and the deviatoric stress component is amended according to stress state, resulting in a more accurate description of the concrete’s response under multi-axial stress state. Finally, through several numerical simulations it is proved that the proposed model has the capability of simulating typical nonlinear performances of concrete material.

Abstract: Microtremors was developed to inverse S-wave velocity structure of sites because it costs little and easy to monitor, can be performed at any place even in a densely populated city with non-destructive measurements, the genetic algorithm is widely used in inversion and there are many disadvantages in using genetic algorithms to solve practical problems, so the authors did a lot of efforts to overcome these disadvantages. In order to solve these disadvantages, a coarse-grained parallel genetic algorithm(PGA) based on personal computer cluster was proposed to inverse S-wave velocity structure of shallow soil layer of actual engineering sites, the simulated annealing algorithm and parallel technique message passing interface(MPI) were adopted to implement the coarse-grained parallel compute. The subpopulations were collaboratively optimized through individual migration strategy and the dynamic populations were adopted to balance the computing load. The shallow S-wave velocity structures of two examples and the actual engineering sites were inversed through a 4-node PC cluster test system, the results showed that the algorithm has a good parallel efficiency and can be used in engineering site.