My project is related to vibration isolation by filled geofoam barrier. I am planning to do a field test and make a filled geofoam barrier (with dimensions of 0.25m width- 4m depth and 20m long) on the front of the vibration source (can be a shaker) and measure the soil displacement before and after making a filled trench on the ground surface. However, first I want to do my field test based on an open trench, which stability of open trench is the most important problem. I found that Hydro-dig Excavation can be a good idea for digging a slot trench but I don't have any idea for the stability of open trench. Do you have any idea for the stability of open trench in this dimensions? Do you know any company that has such experience for doing this project?
Thanks