| At present,most of the low-rise prefabricated buildings use the traditional light steel keel or lattice light steel system with dense columns in the wall.These two light steel structure walls feel unreal,they can not hang heavy objects at will,and the secondary decoration is inconvenient.In addition,the dense column in the lattice light steel system wall is a small truss,which is formed by connecting square tubes and stamping parts through self-tapping screws.The vertical bearing capacity of the structure is large,and it is difficult to exert its advantages in low-rise buildings.In order to overcome the shortcomings of the traditional light steel structure,this paper proposes a new type of composite wall with light steel frame and light concrete on the basis of referring to a large number of relevant literature at home and abroad.The light steel frame beam is made of standard U-shaped stampings and square rectangular steel pipes connected by self-tapping screws.The frame columns are made of square steel pipes.The light steel frame is filled with light aerated concrete block walls.The composite wall has the advantages of light weight,less on-site wet work,easy processing,and low cost,and has good application prospects in low-rise buildings.In this paper,the single-layer composite wall is taken as the object.Through lowcycle reciprocating loading test and finite element analysis,the lateral resistance of the combined wall is studied and compared with the single-layer light steel frame.The main research contents are as follows:1)The number,size and composition of the two composite walls and two light steel frame specimens used in the lateral resistance test are introduced in detail.Considering that U-shaped parts have two forms: U60 and U100,there are two blocks for the corresponding combination wall.In addition,in order to facilitate comparison,this paper also produced two specimens of light steel frame.2)Described the test device for horizontal lateral resistance test of the combined wall and light steel frame specimens,the loading method of vertical and horizontal loads,introduced the test methods for the strain and horizontal displacement of the four groups of specimens,and given the test results of mechanical properties of different materials such as steel blocks and mortar.3)The horizontal and low-cycle reciprocating loading tests were carried out on the two sets of combined wall and two light steel frames,respectively,and aquired the failure form,hysteresis curve,lateral stiffness,skeleton curve and ductility coefficient of the four sets of specimens.The test results are analyzed and compared.The results show that: if U60 and U100 connectors are used,the ultimate bearing capacity of the composite wall specimen is 3 to 4 times that of the light steel frame specimen;the lateral stiffness of the composite wall specimen is 26 times of the light steel frame test piece;the ductility coefficient of the combined wall test piece is about 3.0,which is 1.6times that of the light steel frame.4)Using the ABAQUS software to carry out the low-cycle reciprocating loading finite element simulation analysis on the two light steel frame specimens;the two light steel frame-light concrete composite wall specimens were simplified to a three-bar model,which was carried out Monotonic finite element analysis under horizontal load.The results of the finite element analysis of the four groups of specimens are compared with the test data,and their result agree well,which proves the rationality and correctness of the simplified finite element model proposed in this paper.The experimental research and finite element analysis results in this paper show that the new composite wall has high lateral bearing capacity and lateral rigidity,and has good energy consumption and ductility,which can be used in low-rise fabricated buildings.The research results of this paper provide reference and basis for the promotion and application of the composite wall. |
PDF Full Text Request