Advanced Materials Research Vols. 163-167

Abstract: Based on the Erdos Dong-sheng Exhibition Center’s structure system, this paper uses finite element analysis software SAP2000 to do integral analysis of a new hybrid structure composed of truss strings and shell. The effects of different sag-span ratios and initial pre-stresses on mechanical behavior and the steel consumption of 11 truss Strings integral Structures are analyzed. Besides, the study may be referable for the design and research on truss strings structure.

Abstract: The masonry-concrete shear wall is a kind of new composite structure developed from the masonry wall, and the seismic behavior of it is better than the traditional one. The article used ANSYS to do the time history analysis for the traditional masonry wall and masonry-concrete shear wall with different characteristic stiffness coefficients, different installation modes of shear walls.The calculation data not only proved researches in reasonable value of characteristic stiffness coefficients, but also about the effects in the seismic ability of different masonry-concrete shear walls installation modes.

Abstract: Based on OpenSEES, nonlinear beam-column element based on fiber model and considered nonlinear shear deformation was used to simulate wall limb; zero-length elements were used to simulate action of prestressing tendon and connecting reinforcement in the interface between coupling beam and wall limb; the hysteretic models of the zero-length elements were established by programming. The low-cyclic loading tests of two PCW specimens were introduced. Results of the numerical analysis and the tests indicate that elasto-plastic performances of PCW can be well simulated by numerical analysis, analysis model based on OpenSEES can be applied to non-linear analysis and of good precision; PCW is of good self-centering ability with little residual deformation after unloading, and damage concentrating in certain parts that can be repaired after earthquake; energy dissipation capacity of PCW is increased because of the connecting reinforcement.

Abstract: As a new bridge system, mechanics behavior study on long-span multi-tower suspension is also very deficiency. The existence of center towers is the origin of performance difference between multi-tower suspension bridge and the traditional one. Based on the Midas/Civil platform, the paper takes a three tower suspension bridge as project reference, establishes finite element models of suspension bridge, which the main span is longer than one kilometer and towers from two to seven. Moreover, the structural property is analyzed separately, which bending moment and displacement effect of girder and tower along with the tower number changes is considered. Natural frequency differences of the model bridges are also paid attention on.

Abstract: Connections with exterior diaphragms are used widely in concrete filled steel tubular structures. The stress distribution regularity of ring plate has crucial influence to the right joint design as well as construction. Finite element simulation is applied to the two common types of connections with stiffener ring. The stress distribution regularity of ring plate a well as the development regularity of dangerous section are studied through changing loading methods and ring plate size . The main conclusions are achieved as follows: (1) The high stress plastic region of the 2 types will all not appear in the beam end, but inner the ring plate .This phenomenon will not be different as the changing of ring plate size. (2) The stress distribution of concentric arc ring plate is accord with the present test conclusions, which is to say, high stress regions are all in the corner of the boundary of beam and ring plate despite one way or two way loading. (3) The high stress region of side curved arc joint ring plate distribute in the 30 degree angle section of ring plate under one way loading, and between the 30 degree angle section of ring plate and the 45 degree inner ring plate under two way loading ,the ultimate stress in 45 degree region is a bit higher than 30 degree ,but penetrated plastic region was formed in the 30 degree section ,which indicates that the dangerous section is still in the 30 degree section. (4)Different loading methods can only change the stress distribution of ring plate but can not change the dangerous section, and even have no influence to the ultimate ring plate stress.

Abstract: Graphite nanosheets prepared through high-temperature oxidation via powdering the expanded graphite. After soaking the expanded graphite with styrene(S) and maleic anhydride(MA) monomers, the polymer (Poly(S-co-MA))/expanded graphite(EG) (PSMA/EG) composite granules were obtained by in situ polymerization. Light microscope，scanning electron microscope and X-ray diffraction characterization were performed. SEM analysis indicate that the expanded graphite was mostly tore to sheets with thickness of 50–80 nm and with diameter of 1μm. Optical micrographs showed that the distribution of graphite platelets is found to be nearly uniform.

Abstract: The first high-rise to be completed in Anhui Province in China adopts concrete-filled steel tubular frame- reinforced concrete tube composite structure, which can be classified as the out-of-codes hybrid structure. The structure analysis model is established through the use of the large-scale general finite element software ABAQUS. The dynamic plastoelastic analytical method based on explicit integration which is not theoretically simplified is used to directly imitate the nonlinear reaction of the structure subject to the seismic force. The deformation, internal force and the damage of the structure are studied through the dynamic plastoelastic time-history analytical method subject to the 7-magnitude rarely met earthquake. The calculation result indicates that the maximum inter-layer displacement angle is 1/366 on the X direction and 1/279 on the Y direction, both of which are smaller than 1/100, thus they meet the standards; except for the local cracks, no obvious compression damage is found on the main bearing wall, no plastic strain is found on the internal steel skeleton of the shear wall and the steel reinforcement of the edge member, and the shear wall is of good earthquake resistance performance. Lastly based on the loading and damage conditions of the components, suggestions for the improved design are put forward.

Abstract: According to deforming properties of the structure in the action of symmetry loads and the assumption to the displacement functions of the equivalent composite box beam, the total potential energy of the structure is obtained. Based on the spline finite point method, the stiffness equations are deduced, which could be used to determine the approximate solution of the through composite truss under the action of double-lines symmetry loads in considering the relative slip between longitudinal beams and concrete slabs on the deck system, the vertical deformation of transverse beams and the shear lag effect of concrete slabs. The mechanics behavior of the thorough composite truss is studied by means of a calculated example.

Abstract: Composite construction’s performance depends greatly on shear effectively transfer between steel and concrete, we usually set shear connector between surface of the two different materials, the connector is a determining factor of combinable capability. Composite open-web plate frame is a new type of composite construction, has good performance in application of large span and large load floor or roof. This paper carries on research on two kind of new shear connectors of the composite open-web plate frame, the shell type shear connector and the block type shear connector, and carried on push-out test, also done vertical pseudo-static analysis on composite open-web plate frame which adapt new connector, study the hysteretic behavior ultimate bearing capacity and damage form. Study shows that, block type shear connector which set additional steel bars has good mechanical properties, it’s a shear only connector; Composite construction which adapt the connector has good capability of energy consumption and higher safety storage under vertical load.

Abstract: Based on the tension field theory, a wrinkling analysis method of equivalent stiffness was proposed. The new method was derived and the feasibility was theoretically proved. And a membrane structure was analyzed by the method. The results show that the correct load responses could be quickly attained right after appearance of wrinkled elements, which indicate that the method can be applied to wrinkling analysis of membrane structures.