A New Pull-Out Technique for In-Place Estimation of Concrete Compressive Strength

Table 1

Main data of the concrete classes.

Class	C8/R10	C25/R30	C30/R37
𝑅𝑐-cubic	17.6	41.1	48.1
𝑅𝑐-std. dev.	0.3	1.5	3.0
𝑅𝑐-CoV%	1.6	3.5	6.3
Density [kN/m^3]	2133	2172	2180
𝑓𝑐-cylindrical	15.5	34.7	40.0
𝑓𝑐-std. dev.	1.3	1.9	2.4
𝑓𝑐-CoV%	8.7	5.6	6.0
Density [kN/m^3]	2150	2179	2171
𝑓𝑐/𝑅𝑐	0.88	0.85	0.84

Legenda.
𝑅_𝑐: cubic compr. strength.
𝑓_𝑐: cylindrical compressive strength.
CoV: coefficient of variation = std. dev./average value ∗ 100.