21 May 2024

Low Sill Control Structure: Physical Modeling Investigation of Riprap Stability Downstream of End Sill

The model investigation reported herein describes the process to model and analyze the stability of scaled riprap in the existing 1:55 Froude-scaled Low Sill Control Structure physical model. The existing model is a fixed-bed model, so modifications were made to create a testing section for the scaled stone. Three separate gradations of scaled riprap were tested at varying boundary conditions (discharge, head and tailwater elevations, and gate openings). Each test was surveyed using lidar for pre to posttest comparisons. It was found that Gradation B remained stable throughout the tests in the physical model.

14 May 2024

Low Sill Control Structure: Physical Modeling Investigation of Velocities Downstream of the End Sill

Abstract: The model investigation reported herein describes the process to measure velocities at various locations downstream of the Low Sill Control Structure using an existing 1:55 Froude-scaled physical model. To collect these measurements, an acoustic-Doppler velocimeter was deployed downstream of the structure at varying locations and depths. A total of 79 velocity measurements were taken across nine flow conditions (discharge, head and tailwater elevations, and gate openings) provided by the US Army Corps of Engineers, New Orleans District.

9 Sep 2021

Mat Sinking Unit Supply Study: Mississippi River Revetment

Abstract: The Mississippi Valley Division (MVD) has maintained the Mississippi River banks for over 80 years. The Mat Sinking Unit (MSU), built in 1946, was considered state-of-the-art at the time. This system is still in operation today and has placed over 1,000 miles of Articulated Concrete Mats along the Mississippi River from Head of Passes, LA, to Cairo, IL. A new MSU has been designed and is expected to be fully mission capable and operational by the 2023 season, which is expected to increase the productivity from 2,000 squares/day up to 8,000 squares/day with double shifts and optimal conditions. This MSU supply study identifies and optimizes the supply chain logistics for increased production rates from the mat fields to the MSU. The production rates investigated for this effort are 2,000 squares/day, 4,000 squares/day, and 6,000 squares/day. RiskyProject® software, which utilizes a Monte Carlo method to determine a range of durations, manpower, and supplies based on logical sequencing is used for this study. The study identifies several potential supply and demand issues with the increased daily production rates. Distance to casting fields, number of barges, and square availability are the major issues to supply increased placement rates identified by this study.