Study On Splicing Technology And Mechanical Properties Of Newly-Prefabricated Light Steel Composite Wall

The traditional residential construction in China basically adopts the method of cast-in-place.Cast-in-place structure is more mature technologically than precast structure and has been widely recognized in the engineering field.However,the cast-in-place structure system has the problems of high cost and long construction period.In recent years,with the continuous development of the construction industry and the environmental protection requirements,relevant departments of the state have continuously formulated new policies and new standards to guarantee and promote the industrialization of new buildings.The prefabricated ecological residence is mainly used for the construction of villages and towns at present.It uses the principle of heat island and the fresh air system to take advantage of natural resources such as geothermal energy and solar energy for indoor temperature and air conditioning.It has the advantages of energy saving and heat preservation,and conforms to the trend of new building industrialization.The main supporting components of the prefabricated ecological house are new light steel composite wall and floor.At present,scholars at home and abroad have carried out a lot of researches on the connection methods of precast concrete wall,but there are still relatively few researches on the assembly and connection of sandwich concrete slabs with steel tube reinforced skeleton.In this paper,a new type of precast light steel composite wall is taken as the research object through the method of combining theoretical design,experimental research and numerical simulation to put forward the connection method of this kind of precast wall and wall,wall and floor.The mechanical and seismic properties of the wall with connection are also studied.The specific contents researched of this thesis are as follows:(1)A new type of connection between precast light steel composite wall and wall is proposed.In order to meet the requirements,the wall is optimized by calculating the horizontal action under rare earthquakes based on the bottom shear force and by calculating the dimensions of the embedded steel bars.This paper presents a new type of connection between the precast light steel wall slab and floor slab.(2)Two quasi-static tests with plant-reinforced grouting and one bias test with bull-leg grouting were completed.Experimental research showed that: in the pseudo static test,the bar used for grouting connection didn't yield;joint cracking did not occur;wall collapsed before the connection did;the elastic displacement angle and elastic-plastic displacement angle of the wall met specification requirements showing that proposed method of connecting the wall panels was acceptable under rare earthquakes.In the bias test,when the load reached the limit for normal use and the limit of bearing capacity,the bracket and concrete surface layer did not crack,indicating that the design of the bracket has enough safety reserves.(3)The finite element software ABAQUS was used to model and analyze three groups of specimens,and the simulation results mostly corresponded to the experiments.On that basis,the factors such as axial compression ratio and planting area are analyzed by a set of parameters,and it is found that the bearing capacity of wall slab first increases with the increase of axial compression ratio,but then drops;it also increases with the dimensions of the embedded steel bars.The construction and improvement of the new connection method of precast light steel plate are put forward.