Experimental Research On Mechanical Properties Of Corrugated Steel Pipe Culvert

At present, most of small bridges and culverts in the road still use reinforced concrete or masonry materials. In the process of subgrade compressive strain and foundation settlement deformation, the pipe culvert built on soft soil foundation is very easy to lead to the destruction. If the corrugated steel pipe culvert with great flexibility and high strength could be put into use, it can greatly improve the adaptive ability of the foundation and basis deformation to slove the uneven settlement of foundation problems, which will cause the damage to the culvert.It is the first application in China to test the mechanical properties of corrugated steel pipe culvert by fiber Bragg grating sensor. Compared with traditional testing techniques, optical fiber sensing technology can easily overcome the shortcomings, such as vulnerable of the environmental impact and electromagnetic interference. After temperature correction, it can reach high precision which is suitbale to long-term monitoring for the the deformation and reliability of engineering structures. Currently, the adaptive engineering research of corrugated steel culver is less in the soft soil with high ground water level. In this paper, two corrugated steel pipe culverts were selected in the northern extended road of Nanjing Yangtze River No.4 Bridge. Experiment tests and numerical computation methods were used to analysis its force characteristics under different fill heights and vehicle loads, summarize the changes in law, refine engineering design elements, to improve the structural design of corrugated steel pipe culverts.The results from experimental tests and finite element analysis show that the steel round pipes have a very large longitudinal deformation compensation capacity after treated with the ripple along its axis. It is able to provide stretching room of the material to adapt to foundation deformation, which can devolop sufficiently on its good force characteristics of radial and axial under the large foundation deformation. So the corrugated steel pipe culvert can dispersion load effect at greater extent to play the advantage of steel structure. Therefore, in the soft soil, expansive soil, collapse loess, permafrost and other adverse geological conditions, it has obvious advantages to use corrugated steel pipe structure for constructing the culvert.