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چکیده
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Designing, calculating, and constructing the bridge piers are the most crucial steps of a bridge-building project, especially when the bridge is constructed in a river passage. Building the inclined-vertical pier group against the flow has been taken into consideration by the researchers. The flow pattern and scour around the inclined-vertical bridge piers’ composition of convergent-vertical, and divergent-vertical transverse in the river’s bend is investigated in this study. Two groups containing six piers (including two rows of three ones) with various inclined-vertical piers on the transverse investigated in the study. The experiments were balanced under the condition of the channel and were carried out in the arch peak. Using a three-dimensional Velocimeter, the speed in different balance and time were measured in order to investigate the flow pattern. The effects of various vertical and inclined bridge pier groups (divergent and convergent), the effects of flow conditions (in the clear water , moving threshold, and a live bed ), the distance between two piers’ rows (the distance ratio of the two piers’ rows with the piers’ diameter equal to 2/4, 3/6, and 4/8) and the pier groups’ location in a 180 degree sharp bend (sections of 60, 90, and 120 degrees) on different parameters such as the maximum scour depth, the channels’ topography changes in the downstream in an experimental condition were investigated. Piers with 5 centimeter diameter were utilized in all of the experiments. The experiments were conducted adjacent to the steady sediments with the average diameter of 1.5 mm. The results indicate that in different flow conditions, the maximum scour depth and the sedimentation balance occurs in the location of 60 degrees and in the lived bed. The calculated measure for them were 416 and 315 percent of the pier’s diameter, respectively. In all of the three conditions provided, the maximum scour depth is due to the convergent-vertical pier groups. However, the di
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