Final answer:
Loam is indeed a geotechnical description of a material type, and a grading curve shows the cumulative mass of soil retained on an ordered series of sieves.
Step-by-step explanation:
In geotechnical engineering, loam is a commonly used term to describe a specific material type. It refers to a soil composition that contains a balanced mixture of sand, silt, and clay particles. Loam is highly desirable for agricultural purposes due to its ability to retain moisture while still allowing for proper drainage.
A grading curve, on the other hand, is a graphical representation of the particle size distribution of a soil sample. It shows the cumulative mass of soil retained on each sieve in an ordered series. The sieves are arranged in decreasing order of mesh size, with the finest sieve at the bottom and the coarsest sieve at the top.
By analyzing the grading curve, geotechnical engineers can gain insights into the soil's composition and properties. They can determine the percentage of different particle sizes present in the soil sample, which is crucial for various engineering applications such as designing foundations, assessing soil stability, and predicting soil behavior under different loading conditions.