Small and Large Deflections in Slabs and Cantilevers Using Isogeometric and Finite Element Analysis Approach: Implications for Buildings under Erosion Effects

Abstract

In this study, the deflection behaviour of structural elements was reviewed in detail in
order to ascertain the possible failure behaviour of structures in erosion prone regions of
Anambra State. The study was approached using isogeometric and finite element analysis using
MATLAB and C++ programming language. The study focused more on deflection sensitive
structural components such as plates and cantilevers. Using isogeometric analysis (IGA), the
small deflection of a 6m x 6m clamped plate subjected to a serviceability pressure load was found
to be 0.0627% more than the exact solution. IGA gave better result than finite element analysis
carried out using StaadPro software (matrix size: 20 x 20) which was 1.1173% higher than the
exact solution. Using Mindlin plate theory (incorporating shear deformation), IGA results were
0.1856% higher than finite element analysis result. On considering the large deformation of the
square plate element at serviceability limit state at 100 iteration steps, the results show that the
maximum deflection was 1.613mm, exactly the same with small deflection theory. At ultimate
limit state (failure load), the result from large deflection analysis increased to 2.375mm
(32.084% increase) at 100 iteration steps.