Applied Load Test 2

During Week 6 lab we performed another applied load test. This time, the soil was dry and a new slope was built. The measurements for the initial slope are shown in the picture:

After 30 minutes of applied pressure, the calculations gave an angle greater than the initial angle.

This is inconsistent with predicted soil erosion. There could have been errors in measurements that caused this inconsistency. For improvements, we can make the initial slope steeper. We will continue to test. Our hope is to find a slope that will fail so that we can implement our solutions to stabilize it.

Week 6 Lab goals

The main goal of the lab today is to get the rain rate down and getting the consistency of it. We are also testing the slope under pressure to see how it reacts under pressure

Group Meeting on May 2nd

Meeting goals for tonight are to figure out why some images are not showing up on the site, finish the blog for the blog check, final report drafting and when and where to test next.

Drying the Soil

As mentioned previously, the testing needs to be done while the soil is drier. It does not need to be entirely dried out, as in nature it is possible for a rainstorm to occur before the soil has dried from previous precipitation, but the soil should be around the natural state in which we obtained it. (The soil from southern New Jersey should be very dry, while the soil from Pennsylvania woods is naturally dense). Due to our time constraints we decided to speed the process by using a hair dryer to take moisture out of the soil. With this in mind our next rain simulation will only be done when absolutely necessary.

Blow Drying the Soil:
We took 2-3 "garden-shovel-fulls" at a time in a separate plastic container. We placed the lid over half of the box and used flexible cardboard to keep soil from escaping out the back and the remainder of the top of the box.

Here are some before and after pictures of the soil.

Applied Load Test

This weekend the team decided to conduct a test with only a load applied to the slope (no other factors tested). The slope was built at approximately a 45 degree angle, steeper than built before. At this point in the project, we want the slope to fail so that we can test our solutions to fix that same kind of slope. We placed two bricks on the top of the slope which created a load of approximately 98 N. After watching for 30 minutes, there was no change or collapse in the slope.

The problem with this test was that the soil was still wet from our previous rain simulation. The moisture in the soil caused it to be very closely packed which would prevent it from failure under our tests. The next applied load test will be conducted when the soil is dried out.