Open AccessEffect of soil compressibility on the structural response of box culverts using finite element approach
Author(s) -
O.U. Ubani,
Charles M. O. Nwaiwu,
J. I. Obiora,
E.O. Mezie
Publication year - 2020
Publication title -
nigerian journal of technology
Language(s) - English
Resource type - Journals
eISSN - 2467-8821
pISSN - 0331-8443
DOI - 10.4314/njt.v39i1.5
Subject(s) - culvert , compressibility , geotechnical engineering , subgrade , bending moment , structural engineering , stiffness , geology , finite element method , settlement (finance) , engineering , mechanics , physics , world wide web , computer science , payment
The structural response of box culverts to variable soil compressibility condition was studied in this paper. This was made possible by modelling the soil as springs, and varying the spring stiffness which was represented by the modulus of subgrade reaction of the soil. The results showed that the values of maximum bending moments for gravity actions on box culverts increased linearly with modulus of subgrade reaction, but remained within close values. The results also showed good agreement with results from literature for highly compressible soils. However, for incompressible soil condition, results from standard tables in literature were more conservative with about 10% difference for gravity actions, and 21% difference for lateral actions. The term ‘highly compressible’ that was used in literature for manual analysis was discovered to be more valid for lateral load cases than for gravity load cases. Subsequently, the variations of other action effects such as shear force, axial force, torsion, and soil spring settlement with modulus of subgrade reaction were also studied.
Keywords: Box Culvert, Modulus of Subgrade Reaction, Soil Settlement, Staad Pro.