Midterm Exam Questions

Hi, Maja, in 2008 midterm , how to identify the soil structure, I can only tell that the first one is sand and second one might be clay since it has higher water retentive ability, for structure, should I answer something like spheroid, blocky? Thank you!

To have such a flat water retention curve, as shown in the 2008 midterm, soil #2 could only be a massive (i.e. structureless) clay. Any other clay textured soil with any formation of stable aggregates would not have such a flat water retention curve. Such shape of the water retention curve is indicative that the soil is only having small pores, and that can only be the case in a massive clay.