Advanced Materials Research Vols. 163-167

Abstract: Shaking table tests and theoretical analysis were conducted to study of the seismic response of cable net facade. Firstly dynamic response of cable net façade under earthquake was investigated with shaking table test. Then a numerical simulation model of cable net façade was built for the dynamic analysis .And then with this model the seismic response was analyzed theoretically. The study indicates that: the seismic response of the cable net with glass panels and the cable net on most occasions are mainly decided by the symmetric modes, and the first vibration mode is dominant. The damping of cable net facade is mainly decided by glass panels.

Abstract: Large non-anchored welded steel oil tanks are important equipments that are renowned for their extremely large structures, they are vulnerable to elephant’s foot buckling failure which can cause serious damages in seismic. Generally, locations of tank openings are at the first layer of shell course which are just close to elephant’s foot buckling position of oil tanks. While learning the effect of openings on elephant’s foot buckling of oil tanks, the welding residual deformation was assumed to be initial geometric imperfections. Numerical simulation method was adopted to analyze the effect of three factors (oil tanks with or without openings, opening sizes and opening positions) on elephant’s foot buckling critical load of oil tanks. Results show that the openings and reinforcement plates are beneficial to the increase of buckling critical load; the size and location of the openings have little effect on the buckling critical load.

Abstract: The design scheme of a suspension bridge with a super-long-span of 3300 m was taken as an example, and calculating results from 3 mechanics models are compared with each other to study the effects of bending stiffness of cables on stress distribution and curve shape in super-long single suspension cable structures on the basis of the Finite Element Method (FEM) algorithm of ANSYS and the analytical segmental catenary method for cables’ shape-finding. The study shows that the influence of bending stiffness on curve shape-finding of cables is negligible; Although its effects on stress distribution in cross sections of main cables due to dead loads is small, the error of horizontal forces probably results in great one for the calculation of bending moments at the bottom cross-sections of bridge pylons, which needs attention to ensure the structural safety.

Abstract: A test to study the spatial hysteretic behavior of circular steel pipe subjected to cyclic load was designed. The test setup and data acquisition system were applicable for three-dimension load. A total of 30 specimens were selected by cross section and height of the circular steel pipe to cover different slenderness ratios, different load modes. The specimens were divided into five groups by different load modes. The hysteretic curves changing with different slenderness ratios and different load modes were got after completing the experiment. These lay the foundation of the subsequent research on constitutive model about steel.

Abstract: Eccentric loading experiment of 13 steel tube-reinforced concrete columns and a reinforced concrete column is implemented. The whole process from the start load on the steel tube-reinforced concrete column until damage has been researched. Change of ultimate bearing capacity with eccentricity, longitudinal reinforcement ratio, position coefficient has been studied, and deflection curve and load-vertical displacement curve under eccentric compressive load were obtained. Failure characteristics of steel tube-reinforced concrete were divided into two different type, small eccentric damage and big eccentric damage. With the same conditions, when steel tube ratio of steel tube-reinforced concrete was 2%, its ultimate bearing capacity was nearly double of reinforced concrete columns.

Abstract: GFRP tube filled with steel-reinforced concrete composite column, GSRC, is a new kind of composite column, in which the (shaped steel) reinforcing steel bar is set and the concrete is poured into GFRP tube. Under the action of eccentric loading, the damage signs of the composite columns with smaller and larger eccentricity were respectively that GFRP tube of compressive zone was crushed and the fiber of GFRP tube of tensional zone was ruptured. The tight hoop effect of the concrete given by GFRP tube only existed in compressive zone, and the restriction to the concrete of tensile zone was unobvious. The shaped steel inside GFRP tube had a positive effect on the bending rigidity and the bearing capacity of the member. Using the limit equilibrium theory, the calculation formula of the bearing capacity of GSRC subjected to eccentric loading was created. The calculated results agreed well with the experimental ones.

Abstract: Special-shaped column composed of concrete-filled steel tubes (SCFT) structure, a new type structure, is adopted to a residential building. This paper represents the design and analysis of this structure. 3D model of the structure is built by finite element procedure software and vibration property, static and seismic performance of the building are also analyzed to check the safety of the structure. At last, the vertical stiffener joint of SCFT structure is proposed and calculated. The application of SCFT for residential building represents that the SCFT is suitable for real constructions.

Abstract: As a inclined mega-grid suspend-dome, the prestressing constructi of Dalian gym is very complex. Full-process analysis for the pretensioning scheme should be done before construction. Compared with other pretension methods, a relatively proper scheme of stretching radial cable is put forward and analyzed using construction full-process simulation. The length of active cables without stress is controlled by changing temperature, so pretension is put on cables; Cable tension and removing of temporary support system are simulated using birth and death technology, therefore the structure response of different construction stage and in which stage removing temporary supports is proper are acquired, which provide referenced data for controlling construction safety and precision.

Abstract: Based on the experiment of a one-third scale, single-span, two-storey semi-rigid composite steel frame model with cross-stiffened steel plate shear wall under lateral cyclic loadings, the interactive effect between the joint stiffness and the cross-stiffened steel plate shear wall, the failure mode and energy dissipation mechanism of the structure system were analyzed, some important parameters were obtained in regard to load-carrying capacity, ductility, stiffness and energy dissipation capacity. The results showed that the specimen exhibited excellent ductility, energy dissipation capacity and great safety margin; the stiffness degradation of the joints was not serious, the requirement of ductility was lowered by setting up infill panels, the cooperative work between the frame and the steel plate shear wall was well; stiffeners improved the force condition of steel panels, increased the stiffness and load-carrying capacity of panels, lightened the pinch of hysteretic loops and reduced the noise and tremor of panels. The failure mode of the structure induced by buckling of stiffeners, local buckling and interactive buckling of infill panels，plastic hinges were formed at the bottom of column and semi-rigid connection, the in-plane deformation of specimen was bending failure. The research provides a basis for engineering application and theoretical analysis of the structural system.

Abstract: To gain further insight into the seismic design of concentrically braced frames as defined by the Canadian and Chinese codes, a comparison of the main design requirements contained in each code is carried out in this paper. The comparison emphasizes on the differences existing in these two code provisions, and the reasons behind them. The issues that are examined include the seismic force resisting systems for braced frames, the height restrictions, the force transferred to the beams in chevron configurations, the slenderness ratios of the bracing members, the width-to-thickness ratios of the brace sections, and the influence of brace connections on the columns. Some additional issues that still remain undefined on the seismic response of these systems and some proposals for further studies are also discussed. It is concluded through this comparison that a number of modifications are still required in order to fully implement a capacity design approach of these systems in both codes.