Environmental Engineering Reference
In-Depth Information
Table 1.
chemical compositions of selected samples (weight %).
sample
eh-10
FV-19
FV-25
Gc-52
lZ-22
TF-32
TF-40
sio
2
41.69
50.53
49.34
43.69
50.76
42.63
46.31
al
2
o
3
11.38
16.34
13.37
13.81
13.53
11.83
16.33
cao
11.35
7.09
9.36
9.34
9.45
11.07
9.40
Fe
2
o
3
16.39
9.8
12.35
12.5
11.63
14.25
11.89
k
2
o
1.14
2.5
0.68
1.48
0.66
1.35
1.90
Mgo
10.11
1.99
9.76
9.41
9.23
12.02
4.99
Mno
0.19
0.20
0.16
0.18
0.15
0.19
0.21
na
2
o
2.53
4.8
3.19
3.85
2.89
2.80
4.17
P
2
o
5
0.73
1.17
0.4
0.71
0.3
0.81
1.07
Tio
2
5.23
2.73
2.43
3.774
2.38
3.70
3.48
loi
2.89
0.37
0.28
-0.09
-0.77
-0.65
-0.38
Total
100.65
100.04
100.27
99.11
100.33
100.27
100.03
those of lunar basalts. specifically, it will attach
some information about studies and physical evi-
dence of such basalts that have been carried out by
the civil engineering laboratory of the Regional
Ministry of Works (Government of the canary
islands. spain) in collaboration with the centre for
civil engineering studies and Research, ceDeX,
(Ministry of civil Works, spanish Government).
This project that was called “Geotechnical char-
acterization of the volcanic rocks of the canary
islands” provided some of the most significant
data that have been included here.
While this review, are also annexed a number
of basic characteristics of this type of basalt, pro-
duced by nasa, which will complement the study
of rocks from the canary islands. also a paver
robot is being designed to be capable of paving
slabs with lunar basalt that has at its disposal.
The geotechnical project has characterized over
three hundred samples, of which two thirds belong to
Gran canaria and Tenerife and the rest distributed
among the remaining five islands (Rodriguez-losada
and hernandez-Gutierrez 2006; hernandez-Gutier-
rez and Rodriguez-losada 2006; Rodriguez-losada
et al., 2007). of these samples, only we focus on the
vacuolar aphanitic basalts because they have similar
features to those of lunar basalts known from sam-
ples taken on space missions.
We present data on the mineralogy, hardness
and compressive strength indirectly deduced from
tests of simple and quick implementation.
Table 1 shows the analytical results, in which
major elements appear expressed as oxides in
weight percent.
To estimate the mineralogical composition a
ciPW normative mineralogy calculation is used,
based on the typical minerals that may be precipi-
tated from a silicate molten, knowing the chemical
composition. This ciPW norm is especially useful
for the study of volcanic rocks whose microcrystal-
line or glassy textures do not allow a modal mineral
determination through a petrographic study.
Table 2 shows a summary of the ciPW norm of
all the analyzed rocks. it should be noted that because
the iron content is in the form of ferric oxide, for cal-
culation purposes it has been assumed a theoretical
ratio of Feo to 60% in the basaltic rocks.
3
GeoTechnical TesTs on selecTeD
saMPles
several tests for geotechnical characterization of
basaltic samples were carried out. although there
are no more significant data of the studied rocks,
it is possible an indirect estimation of the most
relevant data such as the compressive strength by
means of other data easier to enforce. in addition,
results of triaxial test on one selected sample are
provided.
3.1
Sonic wave propagation
The speed of propagation of these waves depends on
the elastic properties and the specific weight of the
rock. This speed is affected by discontinuities in the
rock so that, when analyzed the changes that have
occurred in the wave, it can get much information
2
GeocheMisTRY anD MineRal
chaRacTeRisaTion oF saMPles
of the total sample seven representative specimens
of different lithotypes were selected.
