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Construction simulation for a shell-shaped single-layer lattice shell located in Yujiapu was conducted based on ANSYS finite element software. According to actual construction process and the element birth and death technology, the stress changing tendency of key components was obtained and lifting process was analyzed in detail. The monitoring scheme was made and conducted to ensure the safety in erection process for the boxed components which were subjected to large axial force, shear force, moment and torsion at the same time. The results derived by monitoring and simulation were compared. The changing course of bearing displacement was calculated by using nonlinear spring element to accurately simulate mechanical property of double bearing. Results show that displacement would occur at each support due to erection sequence and temperature variation, which should be avoided by taking measures. The stress of lifting point is large during integral lifting process and it almost vanishes after unloading. The simulation method was validated by the agreement between results obtained by monitoring and simulation. The stress and displacement of key components are in control and the construction scheme can satisfy the need of construction. [ABSTRACT FROM AUTHOR]

The calculation method for the overall and local stability of thin-walled elliptical column can not be found in current codes. Theoretical analysis and finite element analysis (FEA) were conducted to study the overall and local stability of the ultrahigh and oblique elliptical variable cross-section steel pipe column in a railway station. The boundary condition at the top of the column was perfectly simulated as the spring constraint of the same stiffness. The way of combining FEA with reverse derivation of the Euler formula and defection formula was adopted to obtain the equivalent parameters such as EAeq, Eleq and μeq. It turns out that the bottom of the column is proved to be the most dangerous position. Taking the actual stress of the column into account, the problem of local stability can be solved by the setting of both annular and lengthways stiffening ribs perfectly. The deformation can be controlled at the same time, for the overall rigidity is also strengthened by the ribs. This method can be used as reference to the design of other component of large-diameter and thin-walled section. [ABSTRACT FROM AUTHOR]

Inner concave cable arches are mainly used in the roof of main building of the New Guangzhou Railway Station. As the unbalanced forces of a cable are relatively large where the cable connects struts and changes its direction, sliding resistance of the cable clip significantly affects the bearing capacity of the cable arch. Nonlinear antisliding analysis of the cable clips was carried out with the aid of ABAQUS, and the FEM results were compared with the experimental data of the full size model of the cable clip. The effects of the material nonlinearity, the contact characteristics between cable and clip, and the pre-tightening forces of high-strength bolts were investigated. Using a pseudo-temperature method for tightening, the effects of prestressing scheme and shrinkage of cross section areas of cables on the pre-tightening loss were discussed. The results show that the FEM results agree well with the experimental data. Cable clips of the inner concave arches used in the New Guangzhou Railway Station have good antisliding performance, and they are safe subjected to design loads. The material nonlinearity should be considered in the contact analysis of the cable clips. The anti-sliding stress of a clip is nonlinearly raised by the increase of friction coefficient and pre-tightening force. Further, sliding of cables would damage the channel of the clip and the contact surfaces of the cables, and reduce the anti-sliding performance of the clip. Unavoidable interaction among the bolts can be neatly weakened by adopting optimized scheme of prestressing (symmetrically and diagonally distributed from the center of bolts to the outside), to reduce the pre-tightening loss of the bolts. [ABSTRACT FROM AUTHOR]