The project site where the gate will be built

Project Summary

For the GIIW Bypass Gate Tremie Coverage concrete pour, a large number of truckloads of concrete were required. These loads were delivered by driving the mixer trucks onto flat deck cargo barges, tow the barges to the construction site, and dump the concrete into a Maxcrete hopper on a pump barge for pumping into a placing boom. To make the cement chutes work with the Maxcrete hopper, the pump barge was ballasted down to a minimum freeboard. A total of 6 cargo barges of 150 x 54 ft were used, each shuttling 6 mixer trucks at the time. To load the trucks onto the barge decks, 2 ramps were built, each consisting of an aggregate upslope and an hinged existing steel Ro/Ro ramp.  

Argonautics Marine Engineering attended a test run with 6 loaded mixer trucks at the construction site in New Orleans on October 19, 2009. The following weekend, over 500 concrete truck loads of cement were delivered to the construction site.     

Scope of Work

The project scope included:

• Feasibility check of the cement truck barge concept;

• Stability calculations for the loaded truck barges;

• Calculate the behavior of the barges during the loading of the trucks;

• Deck strength check for the various truck barges;

• Stability calculations for the cement pump barge;

• Design of the cement boom tower foundations;

• Ballast plan for the pump barge with minimum freeboard;

• Stability calculations for a barge loaded with 2 mobile cement pump trucks;

• Verify the strength of the 2 available Ro/Ro ramps;

• Design supports for one of the ramps;

• Witness the truck driving/parking tests;

Project Photographs

The concrete pump barge with 2 elevated pump arms	Testing the Ro/Ro ramp with a loaded cement truck	Test parking the cement truck on the cargo barge	Pouring concrete into the cement hopper on the pump barge