PSI - Issue 28

Zuzana Marcalikova et al. / Procedia Structural Integrity 28 (2020) 950–956 Author name / Structural Integrity Procedia 00 (2019) 000–000

952

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Although the market with reinforcing fibers today is very diverse, its wider use is still limited, among other factors, with insufficient knowledge of mechanical properties. Especially in cases of finite element method with nonlinear analysis detailed input parameters are required (Sucharda and Konecny, 2018). In the paper mechanical properties of fiber reinforced concrete with different types of fibers and different dosage is tested. The aim is to enlarge the knowledge about the influence of type and amount of fibers to the result mechanical properties. 2. Tested fiber reinforced concrete 2.1. Mixture MasterFiber 482 (BASF, 2020) and Dramix® 5D 65/60 BG (Bekaert, 2020) fibers with a dosage of 40 kg/m 3 , 75 kg/m 3 and 110 kg/m 3 were used in the production of fiber reinforced concrete. The parameters of the fibers are given in Tab. 1. The fibers used for the production of fiber reinforced concrete are shown in Fig. 2. Fine-grained concrete proofBeton Baumit© (Baumit, 2020) was selected for the production of fibers reinforced concrete.

Table 1. Basic characteristics of fibers. Material properties

MasterFiber 482

Dramix® 5D 65/60 BG

Fiber shape

Straight

Multi - hooked ends

Bundling

Loose

Glued

Length l [mm] Diameter d [mm] Aspect ratio ( l / d )

13

62

0.20

0.90

65

68

Tensile strength [N/mm 2 ] Modulus of elasticity [GPa]

2200

2300

200

200

Fig. 2. Steel fibers: (a) MasterFiber 482, (b) Dramix® 5D 65/60 BG.

2.2. Laboratory testing and mechanical properties Samples made of plain concrete and two types of fiber reinforced concrete were concreted in the laboratory of VŠB-TU Ostrava. A total of 7 series of samples were made, which differed in the dosage of fibers and the type of fibers. For every samples series, density, cube compressive strength, splitting tensile strength and bending tensile strength were tested. The average values of mechanical properties of plain concrete and fiber reinforced concrete are given in the Tab. 2 and complemented with the information about standard deviation. Compressive strength and splitting tensile strength were tested on cubes with dimensions 150 x 150 x 150 mm. Bending tensile strength was tested on beams with dimensions 150 x 150 x 600 mm. The beams were provided with a notch 25 mm in the middle of a span. Density was determined based on 12 test specimens for every series. Compressive strength and splitting