01555239

Component

Many fiber types are used in fiber reinforced concrete (FRC) pavements. The maximum undamaged defect size (dmax) concept has been applied to predict notch-based fracture in different types of concrete. The definition of "the maximum undamaged defect size" is the maximum size of a defect in a material does not affect or decrease its strength. The present paper applies this concept to different types of fiber reinforced concrete (FRC) pavement, namely, glass fiber reinforced concrete (GFRC) pavement and steel fiber reinforced concrete (SFRC) pavement. Due to the quasi-brittle manner of concrete, various fracture models have been developed to study the crack propagation in the pavement structures. The fracture energy was determined based on the recommendation of the International Union of Laboratories and Experts in Construction Materials, Systems and Structures (RILEM) Committee 50-FMC. An experimental study was carried out to investigate the effect of adding short fibers, steel or glass, in controlling the fracture energy of concrete. The analysis was invoked for constant fiber length of 25 mm. The flexure test of single edge notched and unnotched specimens was performed using three-point bending configuration. Four different values of crack-depth ratios were considered, mainly, 0.00, 0.10, 0.25, and 0.40. Experimental results showed that, the calculated dmax based on RILEM Committee 50-FMC is greater than the maximum aggregate size (MSA). This means that, there is no compatibility between the flexural strength of FRC and its fracture energy calculated based on RILEM Committee 50-FMC. Therefore, a modified calculation of the area of load-deflection curve was suggested to improve the reliability of fracture energy measured based on RILEM Committee 50-FMC. It is found based on this modification that, dmax is less than 0.7 MSA.

This paper was sponsored by TRB committee AFN10 Basic Research and Emerging Technologies Related to Concrete. Alternate title: Evaluation of Fracture Energy Methods Used in Fiber-Reinforced Concrete Pavements by Maximum Undamaged Defect Size Concept

01550057

15-4297

English

12p

2015

Transportation Research Board 94th Annual Meeting

Digital/other

Figures; Photos; References; Tables

Fiber reinforced concrete; Flexural strength; Fracture mechanics; Reinforced concrete pavements; Rigid pavements; Structural deterioration and defects

Fracture energy

Highways; Materials; Pavements; I32: Concrete; I33: Other Materials used in Pavement Layers

Transportation Research Board Annual Meeting 2015 Paper #15-4297

TRIS, TRB, ATRI

Dec 30 2014 1:24PM