Structural Selection And Mechanical Performance Analysis Of Fabricated Box Culvert

With the rapid development of China’s economy,there are more and more highway construction projects,and culverts have been widely used.The cast-in-place culvert structure can no longer meet the needs of actual projects.Compared with cast-in-place culverts,prefabricated assembly culverts effectively and systematically control the construction quality at the source of production,reducing environmental pollution and conducive to environmental protection;and the mechanized assembly of components can save labor,shorten the construction period,and increase formwork utilization At the same time,the components must be stored for a certain period of time after prefabrication,and have a certain age at the time of installation,which can reduce the deformation caused by the shrinkage and creep of the concrete.Although prefabricated culverts have many advantages,there are many types of prefabricated culverts,and no systematic research has been conducted in China.This paper summarizes the characteristics of various culverts on the basis of previous studies,and selects prefabricated box culverts as research objects.Three types of prefabricated circular hinged culverts with different structures are designed.Through numerical simulation analysis and calculation,comparative analysis of different The mechanical properties of the assembled box culvert of the structural form have been selected as the most reasonable one.Carry out the whole construction simulation of the assembled circular hinge box culvert to understand the force response of the assembled circular hinge box culvert in the actual construction process more accurately.The main research work of this paper includes the following aspects:(1)Summarize the existing types of domestic culverts,compare and analyze the advantages and disadvantages of various prefabricated culverts,and select prefabricated box culverts as the research object.Summarize the structural characteristics of various prefabricated box culverts,propose a new structure of upper and lower assembled box culverts,and comparatively analyze the design size parameters of each culvert unit at home and abroad,draw up the research dimensions of each unit of prefabricated box culverts,and The vertical and horizontal connection methods,the detailed structure such as the entrance and exit structure were studied.Three different types of assembled round hinge box culverts were designed,that is,box culverts with hinge heights of 4H / 8,5H / 8,and 6H / 8 respectively.(2)Based on the nonlinear analysis theory,considering the characteristics of material nonlinearity in the reinforced concrete structure and boundary nonlinearity in the circular hinged box culvert structure,using ANSYS finite element analysis software,three different types of circular hinged box culverts were established.Three-dimensional finite element model.The data obtained by finite element calculations are compared and analyzed to study the mechanical properties of different types of assembled box culverts.It is found that 5H / 8 round hinged box culverts are the most reasonable form of box culverts.(3)Apply the ANSYS finite element numerical simulation method to establish a finite element analysis model of the culvert-soil contact entity of the 5H / 8 round hinged box culvert,and use the unit "life and death" function to simulate the entire construction process of the assembled box culvert Then,analyze the deformation and stress size and distribution of the assembled concrete box culvert during construction.