Some further validations and comparison of the Bearing Area Model (BAM) for adhesion of rough surfaces

In the present short note, we attempt further validations and comparisons of a recent simple model for the estimate for adhesion between elastic (hard) rough solids with Gaussian multiple scales of roughness, BAM (Bearing Area Model) belonging to a DMT class of models. In one case, we use the GJP (Generalized Johnson Parameter) model, which is an empirical fit validated on the same (and so far most extensive) set of data on which BAM was validated, namely that of Pastewka and Robbins. In the second case, we compare with another approximate DMT theory, that of Persson and Scaraggi, which turns out extremely close to the BAM model, despite much more complex: GJP however can lead to significant discrepancies.