An exercise in foam, plywood, bricks, rock - and effort!

Building the model inserts and shapes

Based on design concepts that were developed through planning meetings, and brainstorming sessions, the identified concepts were formed - out of about anything that we could get readily, and cheaply!

The insert sections were plywood, with a 2x4 frame, and end plates of plywood. They had 1:2 slope sides, with gradients along the inserts that fit with the 3 sections; 1%, 2%, and 3%.

Click an image to enlarge

Foam Construction

Plywood Insert

Insert Detail

Rapid Construction

Insert Switch

Upper Channel

Lower Channel

Mid Channel 1

Mid Channel 2

 

The model channel

The model was approximately 21 metres (70 feet) long, and about 1.5 metres (4.8 feet) wide, with plexiglas side-walls. The base channel shape (of 8 metres wide bottom, with 1:2 side slopes) was placed, in scale, along the entire length, with 3 removable sections. These were the feature inserts which allowed us to develop a number of "attempts" at what we were trying to create, then to stop the flow, and switch them out.

The portions of the channel which were permanently in place were "pebbled" by spreading a light coat of concrete, then embedding the small pebbles, to simulate the friction from the grouted rip-rap, which would be the manner in which the real course was built. We used small-scale sandbags, and bricks to provide easily movable obstacles, though we also used a lot of small rocks as well.