Study On Semi-rigid Performance Of Beam-column Connections In Container Houses

With the vigorous advocacy of the green building and industrial building,container houses are emerging as a new form of architecture.In order to promote the rapid development of container houses,many scholars at home and abroad have carried out related researches and made some achievements.However,most of the researches were focused on architectural design.There were few researches on structural design and mechanical property,and no systematic theoretical results were formed.In order to further understand the structural characteristics of container houses,the semi-rigid performance of the beam-column connection of container houses was studied in this paper.The container house structure is mainly composed of cold-formed thin-wall steel.Therefore,the research on the beam-column connection of container houses mainly referred to the related research results of the cold-formed thin-walled steel connections.After summarizing the studies on cold-formed thin-walled steel connections at home and abroad,the finite element software ANSYS 15.0 was used to study and analyze the beam-column connection of container houses.This article mainly carried out the following work:(1)The verification of the finite element analysis method.The finite element model of the existing specimen of the Γ-shape beam-column connection of the portal frame was established.The finite element result and the test result were compared and analyzed to verify the feasibility of using the ANSYS finite element software to analyze the performance of the beam-column connection of container houses.(2)The mechanical behavior of the longitudinal beam-column connection of the bottom frame and the top frame of the container house was studied.(a)All connection components of the same type have different stress distributions under different parameters.The initial rotational stiffness,the ultimate bearing capacity and the ultimate bending moment of the connection components all increase with the increase of the thickness of the fastener,the bolt strength and the number of bolts,of which the bolt strength changes most obviously.(b)All connection components show a distinct linear phase at the beginning of the load,ie,they are in the elastic phase.When the loading continues,a nonlinear stage occurs and the slope decreases.At this point,the stiffness of the connections begins to decrease and enter the elastoplastic stage.As the displacement is further increased,the increment of the reaction force P gradually decreases and tends to zero.A longer loading period can be maintained like that,which indicates that the connections have good plastic property.(c)Through the analysis and processing of the finite element results of the beam-column connections,mathematical models for the M?θ curve of the beam-column connections in container houses were established.(3)The effect of the beam-column connection stiffness on structural stiffness was studied.(a)When the relative stiffness of the connection is small,The ratio of the mid-span deflection and the ratio of the lateral displacement of the column top of the rigid frame are relatively large.With the increase of the relative stiffness of the beam-column connection,the ratios gradually decrease.When the relative stiffness β of the connection increases from 0 to 5,the ratio of the displacement of the rigid frame decreases faster.When β ≥ 25,the curve gradually tends to be stable,and the rigid frame displacement ratio is approximately 1.1 at this time,which is in accordance with the rigid connection limit defined by EC3(β=25).(b)By the finite element analysis,the semi-rigid performance of the designed connection components is obvious.In order to reduce the adverse effect of the semi-rigid performance on structural displacement in the practical engineering,the author gave two suggestions in improving the connection structure and increasing the limit of the structure displacement.