A mudstone layer has been sometimes adopted as a support layer for piles of port facilities in Japan. In some cases, the set-up of the vertical bearing capacity of the pile could not be expected in mudstone, however, in case of Yokohama port, it was observed by in-situ pile loading tests.
Our division studies on vertical bearing capacity of pile supported by mudstone.

Further information could be obtained in our paper below.
Mizutani, T., Sugimoto, T., Kikuchi, Y., Kohama, E. and Kubo, T., " Study on set-up effect of vertical bearing capacity of pile supported by mudstone," Proc. of Internatinal symposium on recent and future technologies in coastal developement, Japan, 2010.