The application of hydrodynamic models for simulating the overbank flow patterns and predicting flood water levels in rivers and floodplains have improved significantly over recent years. However, roughness remains a huge uncertainty which cannot be directly measured. This is especially the case for vegetation growth in watercourses and on floodplains which significantly influence the behaviour of a fluvial system through the reduction of flow conveyance. Therefore, it is crucial to understand how the vegetation element can be represented better in the hydrodynamic model. This paper follows the development of vegetative roughness estimation for hydraulic modeling through laboratory experiments and remote sensing. The study concludes that there is a prospect of utilizing data fusion of remote sensing data to accurately estimate the main vegetation properties such as height and density as a parameter to input to calculations of surface roughness for practical applications.
RETROFITTING OF SEISMICALLY DAMAGED MASONRY STRUCTURES USING FRP – A REVIEW
The un-reinforced masonry (URM) buildings constitute a bulk of the building stock in the world and are prone to damage due to earthquakes which, of late, exhibit widespread occurrence. Hence, there is an imperative need for devising cost effective and efficient retrofitting measures for these vulnerable structures. Research in this area so for has resulted in the development of many procedure aimed at enhancement of the performance of URM structures. Traditional approaches include the use of shotcrete, external coatings such as with ferrocement, and strengthening with external steel bracing elements. These procedures though being effective are expensive, disruptive to building residents and render a negative impact on the aesthetic of the building which is an important aspect particularly for seismic buildings. To overcome these short comings, modern techniques such as the use of FRP overlays, use of near surface mounted (NSM) rods and vertical post tensioning have been adopted. In this paper a critical review is made of the various studies on masonry structures retrofitted for enhanced earthquake performance using FRP.
FINITE ELEMENT ANALYSIS OF GLASS FIBRE REINFORCED POLYMER SINGLE AND GLUE LAMINATED SANDWICH BEAMS UNDER FOUR POINT BENDING
A new glass fibre reinforced polymer (GFRP) sandwich panel has been developed for structural applications. This paper discusses the behaviour of single and glue laminated GFRP sandwich beams using three dimensional (3D) non-linear finite element analyses (FEA). A non-linear finite element model was developed to simulate the behaviour of GFRP sandwich beams with different sandwich layers and different shear span to depth ratios. A UMAT subroutine was written in Fortran language to include Hashin model for 3D analysis. The non-linear FE model was applied to a single and glue laminated GFRP sandwich beams under four point bending. The results of the numerical simulations show a good agreement with the experimental results in different failure modes.
WAVELET BASED DYNAMIC DEFORMATION TIME-HISTORY RESPONSE ANALYSIS OF STRUCTURES SUBJECTED TO EARTHQUAKE EXCITATIONS