As the curing process proceeds, both the strength and electrical resistivity (ρmix) of cement-based (or cement-grouted) materials increase, leading to the nondestructive ρmix measurement technique is very appealing in the assessment/monitoring of the quality of cement-grouted materials. However, the strength gain of cement-grouted sands with time differs from the increase in ρmix with time. Thus, the relationship between unconfined compressive strength (UCS) and ρmix can be affected by the curing time. This study evaluated the effect of curing time on the relationship between ρmix and UCS of sands grouted with microcement. The ultimate goal of this study is to estimate UCS over time of cement-grouted sands based on ρmix. Three silica sands with different median particle sizes were grouted with microcement at different water-to-cement ratios (wc) of 1.0, 1.5, and 2.0. Both unconfined compression test and electrical resistivity measurement test were conducted. Results demonstrate that curing time, particle size, and wc influenced both ρmix and UCS of tested grouted sands in a similar manner; therefore, a direct relationship between ρmix and UCS can be established. However, the complex impact of curing time on the relation between UCS and ρmix and the nonlinear increase in UCS with time hinder the capture of adequate interplay between UCS, ρmix, and curing time. Because a nonlinear increase in UCS with time can be represented by hyperbolic model, an estimation method for hyperbolic model parameters is newly suggested in this study based on ρmix at early curing days.
Bibliographical noteFunding Information:
This work is supported by a Korea Agency for Infrastructure Technology Advancement (KAIA) grant funded by the Ministry of Land, Infrastructure and Transport (Grant 21SCIP-C151438-03).
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- Curing time
- Electrical resistivity
- Hyperbolic mode
- Unconfined compressive strength
ASJC Scopus subject areas
- Civil and Structural Engineering
- Geotechnical Engineering and Engineering Geology