| In prefabricated buildings,foamed concrete with nitrogen gas as a new type of enclosure material has high porosity,which greatly reduces the density of wall panels and provides good thermal insulation.To further study the mechanical properties of foamed concrete test blocks,wall panels,and embedded nodes in wall panels,detailed analysis and research on foamed concrete were carried out.As an important part of connecting the enclosure components with the steel frame,the importance of connection nodes is obvious.Currently,research on connection nodes in China is not mature,and common nodes will have some defects during installation and use.Therefore,based on the existing research results,a new type of node based on steel pipe anchorage was proposed.And using ABAQUS finite element simulation tool to study the seismic characteristics of this new type of node.The research mainly includes the following aspects:(1)Through relevant mechanical performance tests,the compressive strength and static compression elastic modulus of foamed concrete with nitrogen gas have reached the expected level.this result meets the requirements of relevant specifications and technical requirements,and provides reliable guarantee for the use of buildings.(2)By studying and testing the mechanical properties of foamed concrete wall panels,including bending capacity,impact resistance,and hanging force,among others.after testing,the experimental results of the wall panels meet the requirements of the"lightweight partition board for building"specification,indicating that the basic mechanical properties of the wall panels meet the standard.(3)A wall panel node tension test was designed,in which six wall panel test blocks with two different embedded depths of the node were selected to measure the load-bearing capacity of the node during the test.The research results show that the tensile force of the node is closely related to the embedded depth of the node and the density of the wall panel.Taking Class B area as an example,when the basic wind pressure is 0.6 k N/m~2,through table statistics and formula calculations,it is known that the node bearing capacity needs to reach at least 3.75 k N to meet the wind load requirements of exterior wall panels within 100 meters height.The minimum bearing capacity of the node can be determined based on experimental data and calculation results,and appropriate embedded depth and wall panel density can be selected to meet the requirements of the project.(4)The purpose of this study is to investigate the effects of S-plate opening length of nodes and number of nodes on wall plates on the bearing capacity of steel frame structures using twelve sets of monotonic loading numerical analysis models.Furthermore,the study focuses on nitrogen-foamed concrete plates,aiming to examine the entire process from the elastic stage to failure,elucidate the failure mechanism and failure mode of the plate,and reveal the impact of node parameters and lightweight wall plate concrete damage on the bearing capacity of steel frame structures,providing a theoretical basis for future improvements and optimizations of steel frame structures.Through twelve sets of low-cycle reversed loading experiments,this study explores the influence of cyclic reciprocating loads on the structure,seismic performance,and energy dissipation of a new connection node.The hysteresis curve of the new connection node exhibits a relatively complete shape that varies under different parameters,but the overall result is relatively stable.During the loading process,the hysteresis curve has a shuttle shape without any apparent pinching phenomenon,indicating that the new type of connection node has good energy dissipation and seismic performance.The skeleton curve’s overall shape can be roughly divided into two stages:the linear elastic stage and the strengthening stage during the loading process.It is worth noting that the bearing capacity does not show any downward trend during the loading process,indicating that the structure has good stability.The cutting stiffness,energy dissipation coefficient,and ductility coefficient of each model have similar shapes and provide valuable reference points for seismic structure design and improvements in seismic performance. |
