Experimental Study And Finite Element Analysis On The Bearing Capacity Of Low Rise Prefabricated Wallboard With Small Shear Span Ratio

At present,the industrialization of prefabricated building and housing is the development trend of the construction industry,and the prefabricated wallboard is an important component in the prefabricated building.At present,the prefabricated shear wall is widely used in the prefabricated buildings,and scholars at home and abroad are relatively mature in the research of the prefabricated shear wall,especially in the connection structure of the prefabricated shear wall and the seismic research,which provides sufficient theoretical basis for the experimental research of the low-rise prefabricated wall panel.On the basis of reading a lot of references,A new type of low-rise assembled wall panel structure is proposed.This kind of low-level fabricated wall panel changes the grouting connection or slurry anchor connection of traditional shear wall into setting slurry connection,and adds edge members on both sides of the wall.At the same time,the shear span ratio of the wall panel is set as small shear span ratio considering the characteristics of large bay and depth.In order to test the bearing capacity of this simplified low-rise prefabricated wall panel under different failure modes,three groups of wall panels with different shear span ratio were tested under low cycle repeated load.The main work completed is as follows:(1)Three groups of low-rise fabricated wall panels with different shear span ratio were tested under 0.05 axial compression ratio for low cycle reciprocating load test.The test preparation was carried out in the early stage of the test,including the design of loading device,measurement scheme,etc.the test data was recorded during the test,and the development trend of test cracks was observed.(2)Through processing the test data,the hysteretic curve,crack distribution,reinforcement strain and other performance parameters of the low-rise fabricated wall panel are obtained,and the failure mode of the low-rise fabricated wall panel is judged.Among them,the failure mode of wall panel with shear span ratio of 1.25 is bending failure,the failure mode of wall panel with shear span ratio of 0.7 is bending shear failure,and the failure mode of wall panel with shear span ratio of 0.5 is shear sliding failure.(3)According to the failure mode of the wall panel,the calculation formula of thebearing capacity of the wall panel is determined,and the calculated value of the bearing capacity of the wall panel is compared with the test results to verify the reliability of the selected formula.According to the characteristic value of the bearing capacity of the wall panel,the bearing capacity of the wall panel is evaluated.(4)On the basis of experiments,a reliable finite element model of low-rise prefabricated wall panel is established.A reliable finite element model is used to calculate the low-rise prefabricated wallboard with shear span ratio of 0.90,1.00 and1.10.The results show that the failure mode of wall panel with shear span ratio of 0.90 is bending shear failure,and the horizontal load at yield is about 370 k N;the failure mode of wall panel with shear span ratio of 1.00 and 1.10 is bending failure,and the horizontal load at yield is about 280 k N and 260 k N.The recommended shear span ratio is 0.70-0.90 for this kind of low-rise prefabricated wall panel.Through the above research work,combined with the actual engineering situation,it is concluded that the shear span ratio of this kind of wall can meet the performance requirements of bearing capacity within a certain range.It provides a theoretical basis for the development and promotion of low-rise prefabricated buildings in the future,and has a positive significance for the development of township construction market.