Title: Pressure-Dependent Shear Behavior of Fresh Concrete
Author(s): Tilo Proske, Christian Scheich, and Moien Rezvani
Publication: Materials Journal
Appears on pages(s): 29-38
Keywords: fresh concrete; rheometer; shear behavior; variable pressure; yield stress
The shear behavior of concrete under pressure was investigated using a special test setup using a cylindrical pressure cell. Fresh concrete is sheared under different pressure levels by an adapted concrete rheometer (vane rheometer). In the present study, several shear tests were conducted on concretes with moderate and high flowability at a constant water-binder ratio (w/b) of 0.4. Additional pressure was applied up to 160 kPa. The consistency of the concrete was varied by choosing paste volumes of 300, 310, and 340 L/m3. The results revealed a significant influence of applied pressure on the measured yield torque or yield stress in early concrete ages, especially for concretes with low and moderate flowability (F3 and F5) or with a relatively high volume fraction of aggregates. However, a notable increase of shear resistance by applied pressure was identified for all concretes at a later age of 90 minutes.