Study on the Applicability of Short Fiber Reinforced Concrete to Precast Concrete Slabs for Slab Track

Research on the interaction between slabs and subsoil involves the field of materials engineering, concrete structures, and geotechnics. In the vast majority of cases, research focuses on only one of these areas, whereas for advanced study and computer simulations, detailed knowledge of the whole task is required. Among the new knowledge and information upon which this article focuses is the evaluation of subsoil stress using specialized pressure cells, along with detailed measurements of the deformation of a fiber-reinforced concrete slab. From a design point of view, this research is focused on the issue of the center of the cross section and the influence of eccentricity. Knowledge in this area is not yet comprehensively available for fiber-reinforced concrete slabs, where 2D deformation sections of the slab and 3D deformation surfaces of the slab are used in experiments. The experimental program includes a centrically and eccentrically loaded slab. These are structural elements that were tested on a specialized device. Both slabs had the same concrete recipe, with a dispersed reinforcement content of 25 kg/m3. The dimensions of the slab were 2000 × 2000 × 150 mm. Laboratory tests assessed compressive strength, the modulus of elasticity, splitting tensile strength, and bending tensile strength. Based on approximate data from the 3D deformation surfaces, an evaluation of the load-displacement diagrams for the center of the slab and for the center of eccentricity was performed. In conclusion, an overall evaluation and discussion of the results relies on experiments and the mechanical properties of fiber-reinforced concrete.

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Shear resistance of ultra-high-performance concrete reinforced with hybrid steel fiber subjected to impact loading

Journal of Science and Technology in Civil Engineering (STCE) - NUCE ◽

10.31814/stce.nuce2019-13(1)-02 ◽

2019 ◽

Vol 13 (1) ◽

pp. 12-20 ◽

Cited By ~ 1

Author(s):

Pham Thai Hoan ◽

Ngo Tri Thuong

Keyword(s):

Reinforced Concrete ◽

High Performance ◽

Steel Fiber ◽

High Strain ◽

Shear Resistance ◽

Short Fiber ◽

Fiber Reinforced Concrete ◽

Strain Rates ◽

Fiber Reinforced ◽

High Strain Rates

This study investigated the synergy in shear response of ultra-high-performance fiber-reinforced concrete (UHPFRCs) containing different contents of long and short smooth steel fiber reinforcements at high strain rates. Shear resistance of two ultra-high-performance mono-fiber-reinforced concrete (UHP-MFRCs): L15S00 (containing 1.5 vol.-% long and 0.0 vol.-% short fiber) or L00S15, and one ultra-high-performance hybrid-fiber-reinforced concrete (UHP-HFRCs): L10S05 (containing 1.0 vol.-% long and 0.5 vol.-% short fiber) at high strain rates of up to 272 s-1 was investigated using a new shear test setup by an improved strain energy frame impact machine (I-SEFIM). The L10S05 generated high synergy in shear strength, shear peak toughness at static rate and high synergy in shear strain, shear peak toughness at high strain rates. Moreover, all the investigated UHPFRCs were sensitive to the applied strain rates, especially in term of shear strength. Keywords: UHPFRCs; shear resistance; synergy effect; strain-rate dependent; impact. Received 23 August 2018, Revised 29 September 2018, Accepted 18 December 2018

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