1.3. Drawing Line PR

1. Plot the dial reading and square root of time i.e T for a pressure increment as shown in figure.

In this step, you are required to create a visual representation by plotting the dial readings alongside the square root of time associated with a pressure increment. This means using a graph where one axis represents the dial reading and the other shows the square root of time (T). By plotting these points accurately, you can begin to analyze the relationship between pressure and time in the context of consolidation.

Think of plotting the dial readings like measuring how a sponge absorbs water over time. As you apply pressure on the sponge, you want to see how quickly it absorbs the liquid. The graph acts like a time-lapse video showing this process.

2. Draw a tangent PQ to the initial portion of the plot as shown in fig.

This step involves drawing a tangent line (PQ) that touches the initial segment of the plot you've created. A tangent line is straight and represents the slope of the curve at that specific point, which can help in understanding how quickly the consolidation begins. It's crucial that this line runs parallel to your curve right at the starting portion of your graph, giving you important insights into the initial behavior of the consolidation process.

Imagine you're pushing a sled on snow. The tangent line at the starting point represents the immediate motion of the sled when you first push it, capturing the sled’s initial acceleration.

3. Draw a line PR such that OR=1.15OQ.

In this step, you draw line PR based on a specific ratio to the previously drawn tangent PQ. The key here is to maintain the relationship where the distance from O to R is 1.15 times the distance from O to Q. This mathematical relationship can be crucial for further calculations and visual assessments in your analysis of the consolidation curve.

Consider scaling a recipe. If you originally have a recipe that serves 4 and you need it to serve 5, you’d calculate what 1.15 times the ingredients would be. In this context, line PR represents those adjusted measurements important for the next steps.

4. The intersection of the line PR with the second portion of the curve i.e point S is marked.

Here, you look for where your newly drawn line PR crosses the second segment of the curve from your initial plot. This point of intersection, referred to as point S, is critical as it helps you understand where the behavior of the consolidation process changes after the initial time you observed. Marking this point will be foundational in the next steps of your analysis.

Imagine running a race. You note the exact moment you pass a mile mark (point S) after starting strong. This point helps you evaluate if you need to adjust your pace or strategy to continue effectively based on your earlier performance.

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