Applied Mechanics and Materials Vols. 351-352

Abstract: Up till now, the design code for the determination of fire resistance of reinforced concrete (RC) columns is essentially based on tabulated data. Clearly, a more scientific approach based on an understanding of the fundamental behavior of columns in fire is timely andwill be useful to structural engineers. This paper develops a straightforward and rational method to predict the fire resistance of RC columns，which is based on the traditional Rankine approach. The effect of shear bond, if included in the Rankine approach, will yield moreaccurate predictions. Material deterioration at elevated temperature with regard to the strength and stability of columns is also quantified.

Abstract: It is easy for the bulky spherical tank to take place wind-induced buckling under wind load, combined with the Daqing region specific practical engineering, simulation analysis of spherical tank system with 15.7m under random wind loads has been carried out by using ANSYS finite element software. The author investigates the mechanical properties of spherical tanks with the actions of self-weight and wind load, and obtains the deformation and stress distribution law of the tank, pillars and drawbars, at last construction suggestions of spherical tank is given, and these can provide technical support for improving the actual design for large spherical tank.

Abstract: The various push-out tests have been performed to investigate the load carrying capacity and ultimate behavior of headed studs in UHPC (Ultra High Performance Concrete), which has high compressive and tensile strength as well as high durability compared to ordinary concrete. The test program included the studs with a diameter of 16mm and 22mm for various aspect ratios (height to depth ratio of a stud) and cover depths. This paper presents the main results of the experimental investigations.

Abstract: A single-mast guyed tower recommended by a UHV DC transmission line was set as an example. To study initial guy cable prestresss influence on guyed towers mechanical properties, the guyed tower under wind load was analyzed with finite element method considering geometry nonlinearity. Result shows: when initial guy cable prestress is less than critical guy cable prestress, with the growth of initial guy cable prestress, nodes displacement decreases, guy cables work stress and leg members axial force stay; when initial guy cable prestress is greater than critical guy cable prestress, with the growth of initial guy cable prestress, nodes displacement stays, guy cables work stress and leg members axial force proceed a linear increase.

Abstract: Based on the test of abnormal exterior joints of Steel Reinforced Concrete (SRC) column and Reinforced Concrete (RC) beam, the paper analyzed the influence on crack resistance behavior by ABAQUS, of the eccentricity of column section, the steel ratio of the joints zone, the concrete strength and the axial compression ratio and so on. The study indicates that the anti-crack capacity of the joints mainly depends on “the minor joint zone”. Based on the computing unit of minor joint core zone, the calculating formula of anti-crack capacity of the joints is deduced.

Abstract: The structural design methods development nowadays allows including the effects of geometric and mechanical nonlinearity of the materials in the analysis itself. The resolution through matrixes methods frequently involves an incremental treatment for load application and a tangent stiffness matrix that bears in mind the nonlinearity. The present paper shows a procedure to evaluate the bar stiffness considering mechanical nonlinearity of materials. For structures of reinforced concrete formed by two materials where each of them has a resistant behavior so different from the other, its appropriated evaluation is, at the same time, necessary and especially complex. The iterative process exposed here provides the equilibrium position of the section to the general case of axial force and biaxial bending taking into account the nonlinear constituent relationships of materials. Once the equilibrium is reached, the relationship between the biaxial moment and the curvature allows the section stiffness module to be derived, from which the bar stiffness will be determined. As an application of the exposed procedure, the iterative process of the equilibrium research in a section of reinforced concrete is showed. At the moment-curvature diagram can be observed the stiffness progressive decreasing as biaxial bending moments are increasing, because of materials nonlinearity stresses and strains and the section inertia reduction produced by concrete cracking.

Abstract: Departure from the stress state of the steel pipe concrete dye column node, axial force, steel pipe column end moments and stained end vertical shear strength Shear strength concrete filled steel tube the formula, using the finite element analysis software ANSYS to establish a three-dimensional nonlinear finite element model, comparing the results calculated by the finite element calculations and formulas seen, the model is applied to the concrete filled steel tube - steel beam finite element nodes analysis.

Abstract: Based on the ANSYS/LS-DYNA software, the analysis for the 40m span geodesic spherical domes under impact load is carried out. By changing the mass of impact object, impact velocity and impact location, the parametric analyses on the dynamic response of the structures under the impact loading are carried out. The three failure modes of the spherical domes are summed up: local dent of structure and global collapse of structure, Punch failure of structure. Then the characteristics of the dynamic response of the structure with different failure mode, such as the impact course, impact load, speed of nodes, displacement of nodes, and stress of bars, are investigated. It is further improvement of failure mode for single-layer reticulated dome under impact.

Abstract: This paper makes research on the stiffness of CFT column and steel beam joint with inner stiffening ring by using finite element analysis (FEA) program ANSYS. Analysis result indicates that the most important factor influencing the stiffness of the joint is the height of cross-section of beam while the thickness of the web plate hardly has any influence on the stiffness. The M-θ model of the CFT joint given by this paper can be used in practical design.

Abstract: For a further study on the fire-resistant performance of steel plate shear wall under overall stage of fire, a numerical analysis model of steel frame filled with steel plate shear wall was built with the finite element software ANSYS. The stress and displacement distribution at different moments were calculated through the thermal structural coupling analysis acording to ISO-834 standard fire curve, by reasonable selection of the thermal parameters, which showed the highest temperature appeared on the heated side of the beam in the process of heating up, while the highest temperature in the stages of cooling and natural cooling appeared in the column-beam connection; The temperature of structure was elevated for 11minutes, then dropped for 64.5minutes and finally the structure was cooled in the air for 60.5minutes. The whole process shows that the lateral load-bearing capacity of the steel frame filled with steel plate shear wall was reduced by about 30 percent, compared to room temperature.