TY  - JOUR
A1  - Ansari, Meisam
A1  - Zacharias, Christin
A1  - Könke, Carsten
T1  - Metaconcrete: An Experimental Study on the Impact of the Core-Coating Inclusions on Mechanical Vibration
JF  - materials
N2  - Resonance vibration of structures is an unpleasant incident that can be conventionally avoided by using a Tuned Mass Damper (TMD). The scope of this paper contains the utilization of engineered inclusions in concrete as damping aggregates to suppress resonance vibration similar to a TMD. The inclusions are composed of a stainless-steel core with a spherical shape coated with silicone. This configuration has been the subject of several studies and it is best known as Metaconcrete. This paper presents the procedure of a free vibration test conducted with two small-scaled concrete beams. The beams exhibited a higher damping ratio after the core-coating element was secured to them. Subsequently, two meso-models of small-scaled beams were created: one representing conventional concrete and the other representing concrete with the core-coating inclusions. The frequency response curves of the models were obtained. The change in the response peak verified the ability of the inclusions to suppress the resonance vibration. This study concludes that the core-coating inclusions can be utilized in concrete as damping aggregates.
KW  - Beton
KW  - Schwingungsdämpfung
KW  - metaconcrete
KW  - damping aggregate
KW  - vibration absorber
Y1  - 2023
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20230315-49370
UR  - https://www.mdpi.com/1996-1944/16/5/1836
VL  - 2023
IS  - Volume 16, Issue 5, article 1836
SP  - 1
EP  - 18
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Ansari, Meisam
A1  - Tartaglione, Fabiola
A1  - Könke, Carsten
T1  - Experimental Validation of Dynamic Response of Small-Scale Metaconcrete Beams at Resonance Vibration
JF  - materials
N2  - Structures and their components experience substantially large vibration amplitudes at resonance, which can cause their failure. The scope of this study is the utilization of silicone-coated steel balls in concrete as damping aggregates to suppress the resonance vibration. The heavy steel cores oscillate with a frequency close to the resonance frequency of the structure. Due to the phase difference between the vibrations of the cores and the structure, the cores counteract the vibration of the structure. The core-coating inclusions are randomly distributed in concrete similar to standard aggregates. This mixture is referred to as metaconcrete. The main goal of this work is to validate the ability of the inclusions to suppress mechanical vibration through laboratory experiments. For this purpose, two small-scale metaconcrete beams were cast and tested. In a free vibration test, the metaconcrete beams exhibited a larger damping ratio compared to a similar beam cast from conventional concrete. The vibration amplitudes of the metaconcrete beams at resonance were measured with a frequency sweep test. In comparison with the conventional concrete beam, both metaconcrete beams demonstrated smaller vibration amplitudes. Both experiments verified an improvement in the dynamic response of the metaconcrete beams at resonance vibration.
KW  - Beton
KW  - metaconcrete
KW  - Schwingungsdämpfung
KW  - damping aggregate
KW  - vibration absorber
KW  - free vibration test
KW  - frequency sweep test
Y1  - 2023
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20230818-64154
UR  - https://www.mdpi.com/1996-1944/16/14/5029
VL  - 2023
IS  - volume 16, issue 14, article 5029
SP  - 1
EP  - 17
PB  - MDPI
CY  - Basel
ER  - 
TY  - THES
A1  - Ansari, Meisam
T1  - Simulation methods for functional and microstructured composite materials
T1  - Simulationsmethoden für funktionalisierte und mikrostrukturierte Verbundwerkstoffe
N2  - In this thesis, a generic model for the post-failure behavior of concrete in tension is proposed. A mesoscale model of concrete representing the heterogeneous nature of concrete is formulated. The mesoscale model is composed of three phases: aggregate, mortar matrix, and the Interfacial Transition Zone between them. Both local and non-local formulations of the damage are implemented and the results are compared. Three homogenization schemes from the literature are employed to obtain the homogenized constitutive relationship for the macroscale model. Three groups of numerical examples are provided.
N2  - In dieser Arbeit wird ein generisches Modell für das nichtlineare Materialverhalten des Betons unter Spannung vorgeschlagen. Ein Mesoskalenmodell wird aufgebildet, welches die heterogene Materialstruktur des Betons darstellt. Das Mesoskalenmodell besteht aus drei Phasen: groben Zuschlägen, Mörtelmatrix und Übergangszone zwischen Zuschlag und Matrix. Es werden sowohl die lokale als auch die nichtlokale Formulierung des Schädigungsgrades implementiert und die Ergebnisse verglichen. Drei Homogenisierungsmethoden aus der Literatur werden verwendet, um die homogenisierte konstitutive Beziehung für das Makroskalenmodell zu erhalten. Drei Gruppen von numerischen Beispielen werden angeführt.
KW  - Simulation
KW  - Verbundwerkstoff
KW  - Beton
KW  - Meso-Scale
KW  - Composite
KW  - Concrete
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20201103-42783
ER  -