Patents by Inventor Andrzej Drescher

Andrzej Drescher has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Bi-axial geomaterial test system
    Patent number: 4885941
    Abstract: A bi-axial compression test apparatus for geomaterial (soil, etc.) samples that is designed to allow free shear band formation and provide measurements of the stress displacement characteristics of the failure zone. A geomaterial sample formed into a specimen comprising a right rectangular prism is surrounded by a thin rubber membrane and is supported by walls along two parallel faces. An axial load is kinematically applied by a plate that is guided to prevent any tilt or eccentricity, while a bottom support plate for the specimen is horizontally guided by a linear bearing that is substantially friction free. All of the surfaces in contact with the specimen are glass lined and lubricated to minimize friction. The assembly of the specimen and its supports is placed in a conventional tri-axial cell in a loading frame so that an axial load can be applied to one end of the specimen and reacted against the bottom plate.
    Type: Grant
    Filed: April 28, 1989
    Date of Patent: December 12, 1989
    Assignee: Regents of the University of Minnesota
    Inventors: Ionnis G. Vardoulakis, Andrzej Drescher
  • Bi-axial geomaterial test system
    Patent number: 4825700
    Abstract: A bi-axial compression test apparatus for geomaterial (soil, etc.) samples that is designed to allow free shear band formation and provide measurements of the stress displacement characteristics of the failure zone. A geomaterial sample formed into a specimen comprising a right rectangular prism is surrounded by a thin rubber membrane and is supported by walls along two parallel faces. An axial load is kinematically applied by a plate that is guided to prevent any tilt or eccentricity, while a bottom support plate for the specimen is horizontally guided by a linear bearing that is substantially friction free. All of the surfaces in contact with the specimen are glass lined and lubricated to minimize friction. The assembly of the specimen and its supports is placed in a conventional tri-axial cell in a loading frame so that an axial load can be applied to one end of the specimen and reacted against the bottom plate.
    Type: Grant
    Filed: June 15, 1988
    Date of Patent: May 2, 1989
    Assignee: Regents of the University of Minnesota
    Inventors: Ioannis G. Vardoulakis, Andrzej Drescher