ESTIMASI GERUSAN LOKAL DI SEKITAR ABUTMENT JEMBATAN TOMPE

LOCAL SCROLL ESTIMATION AROUND THE TOMPE BRIDGE
ABUTMENT
Yunita Novianti, Nina Bariroh Rustiati, Arody Tanga
ABSTRACT
The abutments on the Tompe Bridge have sedimentation around the bodies of the
abutments. When a flood occurs, this sediment will be transported and erode the bottom
of the abutments. This study aims to determine the depth of scour that occurs around the
Tompe Bridge abutments. In this study, samples of bottom sediments and parameters of
the Tompe River were taken directly in the field. Then the bottom sediment samples were
tested in the laboratory to obtain a grain size with a percentage of 50%. The data that has
been obtained is then analyzed using the Laursen and Toch equations and the Froehlich
equation.
The results of the analysis on local scour estimation research around the Tompe
bridge abutment, it can be concluded that the depth of scour that occurs at an
instantaneous speed using the Laursen and Toch method is interpreted to obtain a local
scour value of 2.604 m to 3.272 m, and using the Froehlich method is interpreted to
obtain a local scour value local scour of 1.411 m to 1.469 m. While the scour depth that
occurs at the 25 year return velocity using the Laursen and Toch method is interpreted as
3.992 m, and at the 50 year return rate it is interpreted as 4.083 m, at the 25 year return
speed using the Froehlich method is interpreted as 2.216 m, and on the 50th birthday is
interpreted as 2.262 m.
Keywords: Local Scour, Tompe River Bridge, Abutments, Laursen and Toch Equation,
Froehlich Equation