Thesis researched in the College of Engineering at the University of Basrah (A laboratory study of the elliptic variation of in-situ drift around regular buttresses)
The thesis presented by the student Saja Ibrahim Ahmed included a study of the effect of the basic factors that affect the site erosion around irregular bridge beams, which are represented in the shape of the beam, the shape of the foundation, the foundation level, velocity and Froud number that were studied in the laboratory
This study relied on conducting laboratory experiments to calculate the depth of local erosion around the irregular beams, where five shapes of the irregular beams were used (rectangular, hexagonal, oval, octagonal, rectangular with a circular head) and the foundations used were three shapes (rectangular, oval, rectangle with a circular head)
The dimensional analysis and the SPSS statistical program were used to find a new equation for each type of base used and based on the results of laboratory experiments, where a positional equation was derived to calculate the greatest drift depth.
The thesis aims that the drift around the bridge abutments is one of the important matters in evaluating the safety and security of the bridges. Therefore, it is necessary to study the site drift around the bridges.
The thesis concluded that the best irregular strut which gives the greatest reduction in drift depth and the highest efficiency is
Rectangular pillar with a circular head with a rectangular foundation with a circular head The best location for the foundation level when using all the pillars is when the foundation is below the level of the bottom
It was observed by comparing the recorded laboratory values with the values obtained from the equation, the results were good and the values of the coefficient of determination were equal to (0.891, 0.869, 0.868) for each of the bases (rectangular base with round head, oval base, rectangular base) respectively.
