Page 103 - Riem-Vol6_nº3

448 IBRACON Structures and Materials Journal • 2013 • vol. 6 • nº 3
Numerical analysis of two pile caps with sockets embedded, subject the eccentric compression load
caps boards (sections F and G – Figure [25]) were more solicited
than the sections closer to the board (sections D and I – Figure
[25]). This phenomenon occurred in all models analyzed.
As a function of the difference between the intensity of forces ap-
plied in the pile caps without the presence of the soil (blocks A and
B – Figure [20]), which were bigger, in relation to the blocks mod-
eled with the soil (blocks C and D – Figure [20]), occurred differ-
ences in the intensities of the main compression stress, what was
foreseen, once the rupture of the set soil-structure of the pile caps
C and D occurred by the soil.
Through the values presented in Table [4] it is possible to con-
clude that the sections F and G, in the inferior nodal zone (near
the piles) were more requested, because with the distribution
of the stress deriving from the strut does not happen uniformly
on the “head” of the piles, the regions closer to the column
were the ones which presented higher stress. These results
are similar to the experimental results obtained by Delalibera
& Giongo [25].
According to these results, all analyses developed were performed
using short piles, because it was found that the distribution of the flows
of main compression stress is little influenced by the piles rigidity.
An interesting result observed during these analyses was in rela-
Figure 24 – Flow principal stress compression,
Pile cap D Figure 25 – Nodal sections investigated
tion to standardization of the main stress of compression on the
piles. In blocks B, C and D (see Figure [20]), which had long length
piles, it was checked that the stress were uniformed nearly to 1/3
of the height of the pile shaft.
4. Analysis of variance
The analysis of variance is a statistics test widespread among the
statistical professionals and fundamentally aims at verifying if there
is substantial difference among the averages and if the factors ex-
ercise influence on any dependent variable.
The proposed values can be of qualitative or quantitative origin,
but the dependent variable must be necessarily continuous.
The main application of ANOVA (analysis of variance) is the compari-
son of averages coming from different groups, also called treatments.
There are two kinds of problems to be solved by ANOVA: fixed fac-
tors or random factors. The randomness determines the question
of the problem.
In most of the cases they are risk factors, after all, the second kind
of problem (random) will only emerge when a study involving ran-
dom choice of factors is performed.
The variance analysis is broadly used in several areas. In Civil
Table 4 – Intensities compressive principal stress, considering the influence of the piles and soil
Section Pile cap A Pile cap B Pile cap C Pile cap D
Tensões principais de compressão (MPa)
A
B
C
D = I
E = H
F = G
16,7
11,9
16,7
5,10
10,9
28,3
11,5
7,5
11,5
3,5
7,5
19,5
13,3
22
13,3
4,2
13,3
30,6
11,7
21,3
11,7
2,10
11,7
21,3