Civil Engineering Reference
In-Depth Information
20.4.7
Recommendations
Table 20.2 summarizes the recommendations of BS 8110 concerning the selection of an
appropriate binder under differing severities of exposure to sulfates. The
recommendations also include the minimum amount of cement in the concrete mix to be
produced.
Table 20.2
Recommendations of BS 8110 for concrete exposed to sulfates.
Sulfate content (SO
3
)
Soils
Water
Severity of
exposure
conditions
Total
SO
3
(%)
SO
3
in 1:2
soil/water
extract (g/L)
Minimum
cement content
(kg/m
3
)
Type of cement
recommended
g/L
Moderate
0.2-0.3 1.0-1.9
0.3-
1.2
Any
330
OPC+25-40% PFA
310
OPC+70-90%
GGBFS
310
SRPC or SSC
280
Severe
0.5-1.0 1.9-3.1
1.2-
2.5
OPC+25-40% PFA
380
OPC+70-90%
GGBFS
380
SRPC or SSC
330
Very severe
1.0-2.0 3.1-5.6
2.5-
5.0
SRPC or SSC
370
Extreme
>2.5
>5.6
>5.0
SRPC or SSC with
protective coatings
370
OPC=ordinary Portland cement
SRPC=sulfate-resisting Portland cement
SSC=super-sulfated cement
PFA=pulverized fuel ash
GGBFS=ground granulated blast-furnace slag
