Shear Database and Study of the Parameters Influencing Shear Behavior - On Shear Behavior of Structural Elements Made of Steel Fiber Reinforced Concrete - page 178

8.7.6 Beams with Different Types of Fibers

In this section, the beams of Chap. 6 , tested at the Universitat Polit é cnica de

Val ncia (Spain), are statistically analyzed by means of two different analysis,

combining the compressive strength levels with several types of steel

è

bers with

different lengths, aspect ratio and steel strength.

8.7.6.1 Beams with Different Fibers Types: Analysis I

In Table 8.30 , the constant variables within the same Series are indicated. In
Table 8.31 , the input data for the ANOVA analysis is presented, differencing the
factors (independent variables) of the dependent variable (safety margin, SM). In
this case, the three factors are: compressive strength level (Low, L; Medium, M;
High, H),

bers type (65/40BN, 80/50BN, 80/40BP) and Codes (EHE, MC2010,
RILEM), having all factors three levels. So, the number of complete cases is:

of levels) № of factors =3 3 =27complete cases
The ANOVA table (Table 8.32 ) shows that all main effects and two interactions
have signi

№ complete cases =( №

cant differences, since their p-values are less than 0.05.
By means of LSD intervals (Fig. 8.34 ), in this Series, it can be observed that,
according to the compressive strength level only, there are signi

cant differences
between the low compressive level and the other two. In this particular case, only
beams made with bers 80/50BN have SM signi cantly different than the other two

types. Codes give SM values signi cantly different, being MC2010 the safest and

the RILEM unconservative.
As it can be seen in Table 8.32 , all main effects have a clear in fl uence on the SM;

furthermore, interactions between compressive strength and ber type (AB), and

between ber type and Code (BC) present signi cant differences on SM. By means

Table 8.30 Constant
variables between the beams
within the same series (f c and
f R3 beams-I)

Constant variables
Cross-section shape
ρ (%) = 3.72

3 point test
50 kg/m 3 of steel bers

Table 8.31 Factors and
dependent variable analyzed
in the ANOVA analysis of f c
and f R3 beams-I

Factors (independent variables)
Compressive strength level: Low (L), Medium (M), High (H)
Fibers type: 65/40BN, 80/50BN, 80/40BP
Codes: EHE08, MC2010, RILEM
Dependent variable
Shear safety margin (SM)