72
D. Kocáb et al.
Table 3 Frequency f L values and RDM(FL) values calculated from f L after F-T cycles (c.)
Specimen
Natural frequency f L (Hz)
RDM (FL) (%)
0 c.
25 c.
50 c.
0 c.
25 c.
50 c.
A1
12,418
8200
–
100.0
43.6
–
A2
12,468
10,753
8189
100.0
74.4
43.1
A3
12,804
9288
–
100.0
52.6
–
A4
12,485
–
–
100.0
–
–
A5
12,669
11,564
8688
100.0
83.3
47.0
B1
11,731
10,355
–
100.0
77.9
–
B2
11,462
10,995
10,867
100.0
92.0
89.9
B3
10,557
–
–
100.0
–
–
B4
12,150
11,566
11,254
100.0
90.6
85.8
B5
11,345
10,891
–
100.0
92.2
–
Average—concrete A
62.7
45.1
Average—concrete B
91.5
93.3
Average—both concretes
75.7
65.9
Table 4 Results for the tensile splitting strength f ct and the frost resistance coefficients after F-T
cycles (c.)
Specimen
Tensile splitting strength f ct
(N/mm 2 )
Frost resistance coefficient (%)
0 c.
25 c.
50 c.
0 c.
25 c.
50 c.
A1
–
2.14
–
–
63.4
–
A2
–
–
2.18
–
–
64.7
A3
–
3.56
–
–
105.4
–
A4
3.37
–
–
100.0
–
–
A5
–
–
2.51
–
–
74.4
B1
–
1.25
–
–
58.8
–
B2
–
–
1.54
–
–
72.3
B3
2.13
–
–
100.0
–
–
B4
–
–
2.01
–
–
94.3
B5
–
1.95
–
–
91.5
–
Average—concrete A
84.4
69.6
Average—concrete B
75.1
83.3
Average—both concretes
80.8
74.9