Its well known that standard probes for rheometers like cylinder-cylinder system doesn't work well for building materials like mortars and pastes. Due to the segregation of the coarse and the liquid phase the so called wall slippage may be occure. 
This may be reduced by rough or ripped surfaces of the probes. Another suggestion is to replace the adhesion forces between the wall and the-material by cohesion effects between the material itself. A shearing two layers of material may be approximated if you build up a layer of material with a filigrane structure of meshes.
Based on the operation principle a known double ring-gap probe is enhanced by a special designed inner cylinder. Its not a rigid but structured like a basket.
Prerequesite for using this probe is a stable fluid like:
Patent pending
A scientific paper from Prof. R. Vogel you will find here and another in German here
V0014 Basket Probe
