To overcome this problem, many investigators use a gravel template, sometimes referred to as a gravelometer or pebblemeter, to classify particles into size classes. Effectively, the gravelometer produces the same results as sieving while minimizing operator error which can arise from measuring the intermediate axis using a ruler. Various configurations have been tried. An example of one design is shown in Figure 1, the design used by our testers. An alternative template design is shown in Figure 2.
Dimensions are in millimeters.
Constructed from 4.76 mm aluminum plate. Bed material sampling in gravel-bed streams. It avoids bias for irregular particles, replicates sieving so you can blend and compare sieved and counted data, and it's faster than a ruler. An alternative gravel template design. Accuracy of surface samples from gravel bed material.