Study On The Effects Of Different Transverse Connected Forms On Mechanical Property Of Pipe Roofing Structure

Steel Tube Slab method is kind of underground engineering construction method based on single tube jacking.All single tubes are made into tube arrays by medial flange plate and bolt component,and injected with concrete in it to generate pipe roofing structure.Excavation work shall be done with the protection of pipe roofing structure.Pipe roofing method supporting system has its unique advantage when crossing the urban arterial road under the super shallow buried geologic condition.STS method has not been used in the domestic.Because the joint of pipe roofing structure is weak,the paper researched mechanical properties to different connection form of connection parameters.Numerical simulation method is used in this paper to analyze the pipe roofing system of different kinds of connection relying on the northeast large street station transferred by metro line 10 and the planning 7 in Shenyang.The flexural behavior of the STS structure,the small steel tube connection form and steel plate connection form derived from STS structure was investigated by using finite element software ABAQUS.The effects of the flexural performance for different parameters are discussed in this paper in three connection forms using single variable control method.By transforming the parameters for connection parts from this three kinds of pipe roofing components and analyzing the working mechanism of pipe roofing component and change law of bearing capacity and stiffness,influence law for all parameters can be acquired.Considering the numerical analysis of this three pipe roofing construction method,there are some laws as follows.With the component of three connection forms,the degree of its bearing capacity and stiffness ranks from high to low as follows:STS construction method>concrete steel connection form>steel pipe connection form.With the component for STS construction method,welding condition affects the most on the bearing capacity and stiffness,wall thickness ranks second,upper and lower distance the third and concrete strength grade does the least.With the component for small steel pipe connection form,the degree ranks from high to low as follows:eccentricity distance of small steel pipe,diameter,wall thickness,intermediate embedded steel.With the component for concrete steel connection form,the degree ranks from high to low as follows:upper and lower distance of flange plate,wall thickness of flange plate,concrete strength grade.By calculating the bearing capacity of all components under the most unfavorable condition,it shows that they all meet the requirement of the bearing capacity.