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To study the seismic performance of RC shear wall, and to develop its fine nonlinear analysis method, systemic studies on nonlinear static analysis and it’s realization method are carried out. Beginning with rotating-angle softened-truss model for coupled shear and flexural responses, analytical model of solid wall is presented based on the comparative study on four types of constitutive law of concrete for confined concrete of boundary zone. Good agreements between analytical and experimental results of load-displacement relation are found, which indicates that the proposed analytical method can reflect the global mechanical behavior of shear wall well. Studies on coupling beam and global perforated wall modeling are implemented, then modeling approach and nonlinear static analysis method for perforated wall are proposed. Comparing analytical load-displacement curve to experimental, initial stiffness and first turning point agree well and analytical ultimate capacity is close to experimental, which is shown that the load-displacement curve can actually exhibit the general load-displacement trend of perforated wall.

Xijiang River Bridge is the first hybrid railway bridge composed of single pylon cable-stayed and continuous rigid-frame system in China. To study the mechanical behaviors of the novel bridge, 3-D finite element model (FEM) based on Midas/Civil software is created; spatial effect of stayed cable is discussed; the self-vibration behavior of this unique bridge is analyzed by adopting the subspace iteration method; then by means of simulating analysis of the whole construction process, stress paths of critical parts in different construction stages are calculated and presented to study its mechanical behaviors. Results reveal that the composite bridge embodies features of both traditional cable-stayed bridge and rigid-frame bridge. Further study, however, shows that the unique hybrid system is mostly characterized by the rigid-frame type, meanwhile, as safety storage, the stay cable will play an important role in the “stiffness kept” of the whole structure, improving the actual stress and working condition of the whole structure in the long run.

Strip shape defects, especially the crown problem, once appeared in the production of hot-rolled strip steel in SG Company. The macroscopic characteristic is the thickness difference occurred between the center and edge cross section of hot-rolled plate. Morphological characteristics and forming reasons can be got by analyzing roll wear. Research shows that the main reason for the formation of crown is excessive attrition of work roll in later period, which leading to smaller roll shape. Therefore, shape defects have been effectively controlled after introducing CVC roll contour technology to optimize roll shape. Quality qualified rate of strip shape of hot-rolled strip steel is more than 99.6% percent, and it has been successfully put into application of hot rolling mill.

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