Research On High Fill Culvert Structure

With the more and more high grade highway construction in mountainous area,in order to meet the requirements of the standard of high grade highway alignment,high fill subgrade is common highway roadbed structure.The part of the general high embankment in order to meet the requirements of the drainage and pedestrian,in these sections must be of high fill culvert construction.And now the current specification,design manual for high fill culvert structure design are not made clear,if simply applies the current calculation method,makes the high fill culvert structure design is too conservative or unsafe,resulting in high fill culvert to produce all kinds of diseases in the actual application,seriously affected the normal operation of high grade highway.Therefore,the study on the structure of high fill culvert has important significance for high fill culvert structure design and application,in this paper,using the finite element software ANSYS to carry out a comprehensive study of the problem of high fill culvert structure,the main contents of this study are summarized as follows:?This paper introduces several main earth pressure theory,and analyzes their applicability and limitation compared.?This paper introduces the finite element analysis of high fill culvert structure principles,methods,steps and material constitutive model,the cover plate culvert,arch culvert,the pipe culvert of section size,modeling using finite element techniques,analysis of the force characteristics of their structure under different working conditions.For the cover plate culvert,the culvert top filling height,span as the research object,analysis of culvert intermediate stress maximum and with increase of height and span filling increases,the middle section is suggested to design the control section,the conclusion and structural mechanics computation results in the same.For the arch culvert,the culvert top filling height,net span,rise span ratio,filling material parameters(elastic modulus,Poisson's ratio)as the object of analysis,a comprehensive analysis of the arch culvert stress characteristics.Get inside the vault under tensile stress,and increases with height,span,rise to fill the cross ratio increasing,and decreases with the increase of the Poisson's ratio,and even the emergence of compressive stress,and the elastic modulus influence on the structure is negligible.For circular pipe culvert,the culvert top filling height,aperture as the research object,analysis of pipe culvert stress increases with the filling height,diameter,the top of the tube,the bottom of the tube,the middle of the pipe stress is maximum,suggestions on the cross section of the top,bottom,the middle for the design of control surface.?The structure load method(cover culvert culvert soil pressure is calculated by using soil column method)and compares the calculated results with the finite element calculation results,found that the calculation results from the two methods are consistent,ratio of finite element calculation results and structure load method results in increased with the increase of span,span from 2m to 5m,ratio increases from 0.80 to 1.8.?The arch culvert structure load method(a soil column method calculating soil pressure)and compares the calculated results with the finite element calculation results,found the results of the two methods are basically the same,but the top inner side tension value calculation results of the two calculation methods have great difference.? The circular pipe culvert structure load method(a soil column method calculating soil pressure)and compares the calculated results with the finite element calculation results,found the results of the two methods are basically the same,for the same span the same position and different fill height the ratio of calculation results with finite element method and structure load method is consistent.the top of the pipe and pipe bottom of the finite element calculation results is bigger than the load structure method calculation results,intermediate results are basically equal,lateral tensile stress or even less than the structure load calculation results.?Combining with the finite element calculation result of the three types of culverts and comparison of structure load method,using the culvert structure design software,map of standard culvert under different fill height,to provide services for high fill culvert structure design,construction.