The lining system, used in tunnel boring machines, is made of precast concrete segments. use steel fibers this kind support system can not only decrease production time and costs but also improve compressive, tensile as well flexural behaviors. A study has been carried out to examine the mechanical properties segments Tabriz metro line-2 project using three types fibers: 3D, 4D, 5D. Various exp...

This work presents a lattice-particle model for the analysis of steel fiber-reinforced concrete (SFRC). In this approach, fibers are explicitly modeled and connected to the concrete matrix lattice via interface elements. The interface behavior was calibrated by means of pullout tests and a range for the bond properties is proposed. The model was validated with analytical and experimental result...

Recently, the need to increase the strength of reinforced concrete members has become a subject that civil engineers are interested in tackling. Of the many proposed solutions, fiber-reinforced polymer (FRP) materials have attracted attention due to their superior properties, such as high strength-to-weight ratio, high energy absorption and excellent corrosion resistance. FRP wrapping of concre...

This work deals with the development of a mechanics-based shear model for reinforced concrete (RC) elements strengthened in shear with fiber-reinforced polymer (FRP) and a design/assessment procedure capable of predicting the failure sequence of resisting elements: the yielding of existing transverse steel ties and the debonding of FRP sheets/strips, while checking the corresponding compressive...

Experimental investigation of GFRP (glass fiber reinforced polymer) tubes that were filled with magnetically driven concrete was carried out to study the flexural behavior of specimens under bending. Specimens having different cross section and lengths were tested. The test specimens were fabricated by filling magnetically driven concrete into the GFRP tubes and the concrete was vibrated using ...

Objective The aim of this study was to examine the properties of fiber-reinforced composite and stainless steel twisted retainers for orthodontic retention. Methods Three different span lengths (5.0, 8.0, and 14.0 mm) of fiber-reinforced composite were investigated. The three fiber-reinforced composite retainer groups were subdivided according to the storage condition (dry and wet), resulting...

When designing steel fiber-reinforced concrete, for example, according to Model Code 2010, the residual flexural strength values must be specified as fundamental properties. It is often difficult establish relationship between and required dosage of fibers depending on type concrete quality. For an estimation presumably necessary fibers, various empirical approaches exist approximate determinat...

FOREWORD Salt-induced reinforcing steel corrosion in concrete bridges has undoubtedly become a considerable economic burden to many State and local transportation agencies. Since the iron in the steel has a natural tendency to revert eventually to its most stable oxide state, this problem will, unfortunately, still be with us, but to a much lesser degree due to the use of various corrosion prot...