Seismic Performance Research On Spatial Forced Units Of Box-Type Steel Structure

Box-type steel structure is a new type of structural system composed of ribbed steel plates.Its design concept is derived from the upper structure of the ship.Its construction method is prefabricated wall panels and floors in the factory.The prefabricated plates are welded and assembled at the construction site.Has the advantages of rapid construction.The upper building structure of the ship will withstand the effects of wind loads,and the first thing that needs to be considered for general civil building structures is earthquake.This paper selects representative spatial forced units to study its seismic performance,and proposes corresponding structural measures and calculation formulas for bearing capacity.Using the finite element analysis software ABAQUS to simulate the failure process of two spatial forced units under horizontal monotonous loads,the difference between the two models is whether there are structural measures at the corners.The results show that the corner construction measures have a significant influence on the bearing capacity and ductility of the spatial forced units.Based on the results of finite element analysis and the functional requirements of the building,four three-story single-open spatial forced unit specimens were designed and fabricated.The main research parameters were the structural measures of the corners of the specimen,and the location and area of the openings.The quasi-static loading tests were carried out on four specimens.The failure process,failure modes,bearing capacity,and hysteresis properties of the specimens were studied.Emphasis was placed on the analysis of the effect of the corner structure and the position and area of the hole on the seismic performance of the specimen.The results show that the plastic deformation of the test specimen without corner reinforcement structure is mainly concentrated on the bottom storey of the specimen.The gable wall panel is not shear-restrained,and the control of the bearing capacity of the specimen is the overturning moment at the bottom of the specimen;When the corner of the specimen has a certain rigidity,after the gable is sheared and yielded,the bottom of the corner is destroyed,the plastic deformation of the gable is more uniform in the event of failure;The reinforced structure of the corner of the specimen improves the bearing capacity and ductility;The presence of the hole will reduce the initial stiffness and bearing capacity and increase the ductility of the specimen;The greater the weakening of the lateral stiffness of the wall plate in the height range of the hole,the lower the initial stiffness of the test piece and the slower the decline of the bearing capacity.The finite element analysis software ABAQUS was used to simulate the test process of the four representative specimens.The results of the comparison between test and the finite element analysis verified the effectiveness of the finite element analysis method used in this paper.Taking the spatial forced unit without a hole as the research object,analyze the influence of ?,? and n on its seismic performance.The results show that ? is the most significant factor affecting the bearing capacity of the spatial force element.According to the results of finite element analysis,the recommended range of the ? is given.Based on the results of the test and the finite element analysis,the failure mode and bearing capacity calculation model are given,and the calculation formula of the lateral bearing capacity of the spatial forced units with corner construction measures is deduced.The specimens with holes can be reduced according to the opening rate,the aspect ratio of the wall and opening.Using examples of finite element analysis to verify the validity of the formula.