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IBRACON Structures and Materials Journal • 2012 • vol. 5 • nº 1
The influence of low temperature on the evolution of concrete strength
In this research, in the middle of this, it was intendded to analyze the
influence of external low temperature of the concrete at early ages in
order to determine their mechanical properties under this condition.
ing, a condition rarely observed. There is no agreement on the
behavior of concrete under low temperature, but positive, even for
the lack of results with these characteristics.
Table 1 – Chemical composition of cement
Mechanical Properties
Testing of cement
Limit Standard
Finesse #200 (75mm)
2,49
≤
12
Finesse #325 (45mm)
10,81
-
2
Finesse Blaine (g/cm )
3472
≥
2600
Initiation take time (min)
190
≥
60
End take time (min)
310
≤
600
Compressive strength, 3 days (MPa)
26,1
≥
10
Compressive strength, 7 days (MPa)
31,3
≥
20
Compressive strength, 28days (MPa)
40,4
≥
32
Chemical Properties
Testing of cement
Limit Standard
Insoluble residue (%)
1,24
≤
2,5
Loss on ignition (%)
4,10
≤
6,5
MgO (%)
1,81
≤
6,5
So (%)
3
2,00
≤
4,0
Na O (%)
2
0,11
-
K O (%)
2
0,71
-
Table 2 – Particle size analysis of fine and coarse aggregate
Opening of sieves (mm)
Fine aggregate
Coarse aggregate
Retained (%)
Accumulated
retained (%)
Retained (%)
Accumulated
retained (%)
# 19
0
0
0
0
# 12,5
0
0
31,6
31,6
# 9,5
0
0
45,2
76,8
# 6,3
0
0
22,6
99,4
# 4,8
0
0
0,6
100
# 2,4
0,3
0,3
0
100
# 1,2
1,1
1,4
0
100
# 0,6
10,4
11,8
0
100
# 0,3
45,5
57,3
0
100
# 0,15
33,2
90,5
0
100
background (< 0,075)
9,5
100
0
100
Fineness modulus
1,61
6,77
Maximum size
1,2 mm
19 mm
Specific gravity
2618 kg/m³
2590 kg/m³
Unit mass released in the state
1419 kg/m³
1197 kg/m³