EFFECT OF NONUNIFORM STRESSES ON MEASURED DSS STRESS-STRAIN BEHAVIOR. DISCUSSION AND CLOSURE

A discussion of a paper with the aforementioned title by DeGroot, Germaine, and Ladd, published in this journal (Volume 120, Number 5, May 1994), is presented. Discussers Dyvik and Lacasse present results from a Geonor direct simple shear (DSS) test conducted at the Norwegian Geotechnical Institute on a rubber specimen that contradict the results of the authors. The results show dilative rather than contractive behavior. The discussers agree with the authors that the DSS device does have certain limitations, but they insist it has a great deal of merit as an engineering tool because it reproduces shearing conditions that no other conventional geotechnical laboratory device can.