Environmental Engineering Reference
In-Depth Information
5.1.3
Apparent density and open porosity
(EN 1936)
six cubic specimens were dried to constant mass
and placed in a vessel to absorb distilled water while
submitted to a standard vacuum. after an immer-
sion period of time, also standard, saturated and
immersed weightings were made. apparent density
and open porosity were calculated according to the
following equations 2 and 3, respectively:
Table 3. Results of cs and Fs for the studied volcanic
natural stones.
Volcanic stones
cs MPa
Fs MPa
s. Miguel Island
Pedra do Porto Formoso
81
13.6
Pedra da Povoação
6
1.4
Basalto da chã das Gatas
32
7.8
Basalto do Bacharel
53
9.5
Pedra do Dâmaso
86
7.7
dried mass
saturated mass
sta. Maria Island
Pedra da Vila do Porto
immersed mass
×
water density
7
3.1
−
Pedra do anal
8
4.7
(2)
saturated mass
−
dried mass
×
100
(3)
Table 4. aD, oP and Wa results obtained for the
studied volcanic natural stones.
saturated mass
−
immersed mass
aD
(kg/m
3
)
oP
(%)
Wa
(%)
5.1.4
Water absorption at atmospheric pressure
(EN 13755)
For this test, six cubic specimens were also used.
The test method is quite similar to the one used
to determine apparent density and open porosity.
The main differences were that vacuum was not
used, the immersion was staged into 3 steps and
specimens were left immersed in water until con-
stant mass was reached. Water absorption was cal-
culated by the ratio between the mass of absorbed
water and the mass of the specimen.
Volcanic stones
s. Miguel Island
Pedra do Porto Formoso
2220
9.4
4.7
Pedra da Povoação
1430
34.6
27.4
Basalto da chã das Gatas
1930
6.5
3.7
Basalto do Bacharel
2160
7.0
3.7
Pedra do Dâmaso
2190
5.2
2.9
sta. Maria Island
Pedra da Vila do Porto
1430
26.0
21.1
Pedra do anal
1630
24.5
16.1
Table 5. Results obtained for iR and aR for the studied
volcanic natural stones.
5.2
Performance after application properties
5.2.1
Rupture energy (EN 14158)
six specimen slabs were used to perform the test.
after placing and levelling the slab on a silica sand
bed of standard grain size, a steel ball of both
standard mass and diameter was dropped on the
upper face centre of the tested slab. on the first
test, the ball was dropped from an initial height of
10 cm and the height was continuously increased,
5 cm each time, until the specimen broke. on the
following five tests the procedure was the same,
except for the initial height of the ball dropping:
15 cm bellow the result obtained on the first test.
Rupture energy
was calculated as the ball work when
dropped from the height which produced specimen
failure, according to the following equation 4:
Volcanic stones
iR Joules
aR mm
s. Miguel Island
Pedra do Porto Formoso
4
23.0
Pedra da Povoação
2
42.5
Basalto da chã das Gatas
4
22.0
Basalto do Bacharel
6
20.0
Pedra do Dâmaso
4
20.0
sta. Maria Island
Pedra da Vila do Porto
3
26.0
Pedra do anal
4
25.5
(Tecnilab 440c). in this machine type, abrasion is
obtained by using both a rotating abrasion wheel
(with standard dimensions and made of a standard
steel) and a standard abrasive powder (white fused
alumina). a certified Reference Material (cRM)—
“Marbre du Boulonnais”—was used to calibrate
the testing machine, but also to correct test results.
The test was carried out under standard conditions
and at the end a groove was obtained in the tested
face. The abrasion resistance value is the chord
dimension measured on the middle of the groove
(4)
Work = Ball mass
××
g
dropping height
where g is the value of gravity acceleration.
5.3
Durability properties
5.3.1
Abrasion resistance (EN 14157)
The faces exposed in use of six specimen slabs were
abraded by means of a capon wearing machine
