On the calibration of cohesive parameters for refractories from notch opening displacements in wedge splitting tests

Cohesive properties of refractory castable at 600 °C: Effect of sintering and testing temperature

“…The last two parameters are the ratio between the CMOD (Δ) and NOD ( ) at the peak load, and the slope of the CMOD vs. NOD curve post-peak, , after the observations and proposal from Ref. [23]. They need to be calibrated since the present setup did not allow for DIC measurements in the CMOD region.…”

“…Five WSTs are analyzed hereafter, namely, the same that were discussed in Refs. [21,22,23]. All the specimens were made with the same material described in the previous section, designated as "MZ".…”

“…Then this mesh was scaled and positioned in the image frame so that the NOD regions (cyan squares) coincided with the measurement zones via DIC [21]. The NOD was then extrapolated to CMOD data [23] as described in the following sections, and applied on two nodes in the force application region (green circles). Quadrilateral elements (Figure 4(b)) were used to define a different section with reduced thickness for the samples that had lateral grooves to guide the crack.…”

“…Although the Young's modulus was calibrated in Ref. [23] for room-temperature experiments (with rather low sensitivities), the higher uncertainty for the 600°C tests led to unrealistic levels. Therefore, the Young's modulus was kept constant and equal to 46 GPa, which was identified for the first experiment discussed in Section 4.…”

“…All the initial parameters are gathered in Table 1, as calibrated in Ref. [23] with the same identification framework.…”