An electromagnetic non-destructive approach to determine dispersion and orientation of fiber reinforced concretes

Autor: Oguzhan Akgol, Murat Ozturk, Umur Korkut Sevim, Muharrem Karaaslan, Emin Unal
Přispěvatelé: Mühendislik ve Doğa Bilimleri Fakültesi -- İnşaat Mühendisliği Bölümü, Mühendislik ve Doğa Bilimleri Fakültesi -- Elektrik-Elektronik Mühendisliği Bölümü, Öztürk, Murat, Sevim, Umur Korkut, Akgöl, Oğuzhan, Karaaslan, Muharrem, Ünal, Emin
Rok vydání: 2019
Předmět:
Vector spaces
Materials science
Horn antennas
Loss factor
Mechanical-properties
Steel Fibers | Self Compacting Concrete | Concrete Slabs
Mechanical properties
Steel fiber
02 engineering and technology
Dielectric
Fiber reinforced materials
Electromagnetic properties
01 natural sciences
law.invention
Electric network analyzers
Engineering
Microwave antennas
Flexural strength
Sfrc
law
Dispersion (optics)
0202 electrical engineering
electronic engineering
information engineering

Dispersion (waves)
Environmental conditions
Fiber
Electrical and Electronic Engineering
Composite material
Linearly polarized antennas
Instruments & Instrumentation
Instrumentation
Electrical impedance
Behavior
Multidisciplinary
Electromagnetic behavior
Vector network analyzers
Applied Mathematics
020208 electrical & electronic engineering
010401 analytical chemistry
Impedance matching (electric)
Radome
Condensed Matter Physics
0104 chemical sciences
Fibers
Reinforced plastics
Electromagnetic techniques
Microwave frequency ranges
Microwave
Zdroj: Measurement. 138:356-367
ISSN: 0263-2241
Popis: WOS: 000464636400034
Including fibers in concretes improves their mechanical properties such as flexural strength, impact load resistance and limited crack propagation. The dispersion, orientation and types of the fibers placed in the concretes affect these mechanical properties. The aim of the study is to propose a standard and a novel prediction method for determining the dispersion and orientation of the concretes in which fibers are reinforced in microwave frequency range. This study demonstrates that determination of both orientation and dispersion of the fibers regardless of the fiber types in concretes is possible by extracting electromagnetic properties of the structures in microwave regime as a nondestructive method. The measurement technique requires sample under test (SUT) and two wideband linearly polarized antennas placed in the front and backside of material under the free space condition. Although there are some studies investigated the fiber content of concrete samples through certain electromagnetic techniques, the proposed novel approach concentrates on the electromagnetic behavior of the fiber reinforced concretes in a very wideband range from 3 GHz to 17 GHz. Unlike the other studies, open space measurement with the help of a vector network analyzer which is capable of measuring up to 43 GHz along with two high gain horn antennas was carried out in the laboratory environment. Time required for exact measurement of dielectric constant and loss factor of the concrete between antennas is less than a minute. A simple and confidential model is carried out to determine both orientation and dispersion of fibers in concrete by observing the changes of dielectric constant and loss factor. The determination of electromagnetic properties of concretes with fibers has potential applications for future nondestructive sensors. In addition, observation of negative dielectric constant and some other electrical properties such as low loss factor and impedance match with free space presented in the study for particular frequency intervals gives a chance for future radome applications in harsh environmental conditions. (C) 2019 Elsevier Ltd. All rights reserved.
Databáze: OpenAIRE