Design And Performance Study Of Laminated Assembly Beam-column Joints

Compared with traditional buildings,prefabricated buildings have the advantages of simple construction,short construction period and less pollution.They are more and more widely used in Chinese architecture.Since the components of the prefabricated building usually adopt the prefabricated and on-site splicing construction methods,the connection of the nodes is an important factor affecting the structural integrity.In view of this,this paper designs a laminated assembled beam-column connection structure,and uses the combination of laboratory test and simulation analysis is used to study the mechanical properties,deformation characteristics and performance influencing factors of the design structure.The main work and related conclusions are as follows.1.Aiming at the problems of weak connection strength,inaccurate construction and poor integrity of existing fabricated beam-column joints,a laminated assembled beam-column connection structure was designed.Compared with the existing beam-column connection structure,the structure is provided with a connecting steel body,a reinforcing gusset,a reinforcing plate and a connecting steel plate,from the perspective of improved bearing performance and accurate positioning of construction hoisting of the structure.2.According to the needs of structural performance testing,a suitable indoor test plan was designed.In the test component,the cast-in-situ beam-column joint test piece and the laminated beam-column joint test piece were prepared respectively,strain test points were arranged inside and on the test piece,and the properties of each component material were tested;In terms of the loading device,the single beam bending loading device in the laboratory is modified to meet the requirements of simultaneous application of lateral loads and vertical loads.3.The prepared test pieces were subjected to compression and shear tests.From the experimental situation,the laminated assembled beam-column joints and the cast-in-place beam-column joints are consistent in terms of deformation characteristics and forces,but the laminated assembled beam-column joints have performance such as compressive performance,deformation resistance and shear strength have a certain improvement compared to cast-in-place beam-column joints.In the change trend of strain and load of steel and concrete,the laminated assembled beam-column joints grows slowly and the strain peak are smaller.In the failure state of the joint,when the laminated assembled beam-column joint is broken,the crack distribution is wider and the number of cracks is more.In the compressive bearing capacity,the laminated assembled beam-column joints are increased by about 10.1% compared with the cast-in-situ beam-column joints.In terms of shear strength.In terms of shear strength,the laminated assembled beam-column joints are about 19.8% higher than the cast-in-place beam-column joints.In the case of cracks,when the same crack length and width are produced,the laminated assembled beam-column joints can add 8%-20% more load than the cast-in-situ beam-column joints.4.A simulation analysis model with consistent laboratory tests was established to simulate and analyze the mechanical behavior and influencing factors of the structure.From the analysis of the situation,the composite beam-column joint specimen model is superior to the cast-in-situ beam-column joint specimen model in the deformation,stress and displacement curve changes.the change of the connecting steel pipe diameter,reinforcing gusset and the bottom reinforcing plate length,top reinforcing plate thickness and the concrete strength will be impact to the structure performance.But from the perspective of simulation and analytic hierarchy analysis,the concrete strength,the diameter of the connecting steel pipe and the length of the reinforcing gusset change have more obvious effects on the structural performance.