Apparatus and method for measuring rutting susceptibility

An apparatus for testing the susceptibility of a test specimen to rutting comprising:

• a specimen holder having at least one cavity defined by walls configured to receive a test specimen, said walls being arranged to laterally support sides of the test specimen along the entire periphery of the test specimen while holding the specimen with a surface thereof exposed for testing;
• a load device positioned adjacent said specimen holder for applying a load to the exposed surface of the test specimen;
• and
• motive means cooperating with said load device and with said specimen holder for passing the load repeatedly in only one direction along a predetermined path of travel extending along the exposed surface of the test specimen for forming a rut in the test specimen.

An apparatus for testing the susceptibility of a test specimen to rutting comprising:

• a specimen holder having a plurality of cavities circularly arranged about a central axis, each cavity configured to receive a test specimen and to laterally support sides of the test specimen while holding the specimen with a surface thereof exposed for testing;
• a loading wheel positioned adjacent said specimen holder for applying a load to an exposed surface of a specimen positioned in said specimen holder;
• means for applying a load to said loading wheel;
• means for rotating said specimen holder about said central axis to cause the loading wheel to follow a predetermined path of travel successively across each of said cavities of said specimen holder for repeatedly applying the load to the test specimens in said specimen holder.

A method for testing the susceptibility of a test specimen to rutting comprising:

• forming a test specimen;
• positioning the specimen with a surface thereof exposed for testing;
• passing a load repeatedly in only one direction along a predetermined path of travel along the exposed surface of the test specimen to form a rut;
• and wherein said step of forming the test specimen comprises forming the specimen in a compact configuration such that the length of said path of travel along the exposed surface of the specimen is no greater than the maximum dimension of the specimen in a direction transverse to said path of travel.

An apparatus for testing the susceptibility of a test specimen to rutting comprising:

• a test specimen;
• a specimen holder having a cavity configured to receive said specimen and to hold the specimen with a surface thereof exposed for testing;
• and
• a load device positioned adjacent said specimen holder and cooperating therewith for repeatedly passing a load along a predetermined path of travel across the exposed surface of the test specimen to form a rut wherein said specimen holder is mounted for rotation relative to said load device, said test specimen being of a compact configuration and said path of travel extending from a first peripheral location to a second peripheral location such that the shortest distance between said peripheral locations across the exposed surface of the specimen is no greater than the maximum dimension of the specimen in a direction transverse to an axis extending between said peripheral locations.

An apparatus for testing the susceptibility of a test specimen to rutting comprising:

• a cylindrical test specimen;
• a specimen holder having a cylindrical cavity configured to receive said cylindrical test specimen and to hold the specimen with an end surface thereof exposed for testing;
• and a load device positioned adjacent said specimen holder and cooperating therewith for passing a load repeatedly in only one direction along the exposed surface of the test specimen to form a rut;
• said load device comprising at least one loading wheel arranged for applying the load repeatedly along said exposed end surface of the test specimen.