Fig. 11

Proposed model for estimating concrete strength based on (a) peak conductance shift, (b) peak frequency shift, and (c) combined effect of peak conductance and peak frequency shift in a 3-D plot.
Proposed model for estimating concrete strength based on (a) peak conductance shift, (b) peak frequency shift, and (c) combined effect of peak conductance and peak frequency shift in a 3-D plot.