Fast penetration probe for characterizing the rheological properties of concrete

A method of acquiring and analyzing properties of a fresh or partially set cement-based material, said method including the steps of:

• (a) penetrating the material with a probe driven at a constant penetration speed by an actuator regulated by a controller;
• (b) for each of a plurality of sampling times, measuring, with a force sensor, a penetration force applied to the probe;
• (c) transmitting, from the force sensor, force data associated with the measured penetration forces to the controller;
• (d) for each of the plurality of sampling times, determining, by the controller, a probe penetration depth based on one or more of the following:
• the force data and actuator position data, wherein the actuator position data is received from the actuator or inferred by the controller;
• (e) recording, by the controller, the determined probe penetration depth;
• (f) for each of the plurality of sampling times, associating, by the controller, the probe penetration depth and the penetration force to form a synchronized pair;
• (g) determining, by a processor, a yield force of the material based on change in relationship between the penetration depth and the penetration force within the synchronized pairs;
• and
• (h) calculating a static yield stress of the material by the processor, based at least in part on the yield force, a probe geometry factor, and an angle of internal friction of the material.