Shear Database and Study of the Parameters Influencing Shear Behavior - On Shear Behavior of Structural Elements Made of Steel Fiber Reinforced Concrete - page 182

Table 8.33 Constant variables between the beams within the same series (f c and f R3 beams-II)
Constant variables
Cross-section shape
ρ (%) = 3.72

3 point test
50 kg/m 3 of steel bers

Table 8.34 Factors and dependent variable analyzed in the ANOVA analysis of f c and f R3
beams-II
Factors (independent variables)
Compressive strength level: Medium (M), High (H)
Fibers type: 45/50BN, 65/40BN, 80/50BN, 80/30BP, 80/40BP
Codes: EHE08, MC2010, RILEM
Dependent variable
Shear safety margin (SM)

Table 8.35 ANOVA for SM on shear — type III sums of squares (f c and f R3 beams-II)
Source of variation Sum of squares d.f Mean square F-ratio p-value

Main effects
A: Compressive strength 0.0264033 1 0.0264033 22.65 0.0014

B: Fiber type 0.213753 4 0.0534383 45.84 0.0000

C: Code 0.148087 2 0.0740433 63.51 0.0000

Interactions
AB 0.119313 4 0.0298283 25.59 0.0001

AC 0.00920667 2 0.00460333 3.95 0.0641

BC 0.0984467 8 0.0123058 10.56 0.0016

Residual 0.00932667 8 0.00116583

Total (corrected) 0.624537 29
All F-ratios are based on the residual mean square error

Code. There are signi cant differences between all Codes. MC2010 is the safest,

and the mean value of SM for RILEM is below the unit. EHE gives SM very
close to the unit.

￿

As it can be seen in Table 8.35 , all main effects have a clear in fl uence on the SM;

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

between cant differences on SM. By means

of surface charts (Figs. 8.39 , 8.40 and 8.41 ), it is possible to evaluate the in

ber type and Code (BC) present signi

fl uence

of the interactions on the shear SM.