1
|
Lyngdoh GA, Doner S, Nayak S, Das S. Finite Element-Based Numerical Simulations to Evaluate the Influence of Wollastonite Microfibers on the Dynamic Compressive Behavior of Cementitious Composites. Materials (Basel) 2021; 14:4435. [PMID: 34442958 DOI: 10.3390/ma14164435] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 07/30/2021] [Accepted: 08/03/2021] [Indexed: 11/17/2022]
Abstract
This paper investigates the dynamic compressive behavior of wollastonite fiber-reinforced cementitious mortars using multiscale numerical simulations. The rate dependent behavior of the multiphase heterogeneous systems is captured in a multiscale framework that implements continuum damage towards effective property prediction. The influence of wollastonite fiber content (% by mass) as cement replacement on the dynamic compressive strength and energy absorption capacity is thereafter elucidated. An average compressive strength gain of 40% is obtained for mortars with 10% wollastonite fiber content as cement replacement, as compared to the control mortar at a strain rate of 200/s. The rate dependent constitutive responses enable the computation of energy absorption, which serves as a comparative measure for elucidating the material resistance to impact loads. Approximately a 45% increase in the dynamic energy absorption capacity is observed for the mixture containing 10% wollastonite fibers, as compared to the control case. Overall, the study establishes wollastonite fibers as a sustainable and dynamic performance-enhanced alternative for partial cement replacement. Moreover, the multiscale numerical simulation approach for performance prediction can provide an efficient means for the materials designers and engineers to optimize the size and dosage of wollastonite fibers for desired mechanical performance under dynamic loading conditions.
Collapse
|
2
|
Blanchard R, Morin C, Malandrino A, Vella A, Sant Z, Hellmich C. Patient-specific fracture risk assessment of vertebrae: A multiscale approach coupling X-ray physics and continuum micromechanics. Int J Numer Method Biomed Eng 2016; 32:e02760. [PMID: 26666734 DOI: 10.1002/cnm.2760] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 10/14/2015] [Indexed: 06/05/2023]
Abstract
While in clinical settings, bone mineral density measured by computed tomography (CT) remains the key indicator for bone fracture risk, there is an ongoing quest for more engineering mechanics-based approaches for safety analyses of the skeleton. This calls for determination of suitable material properties from respective CT data, where the traditional approach consists of regression analyses between attenuation-related grey values and mechanical properties. We here present a physics-oriented approach, considering that elasticity and strength of bone tissue originate from the material microstructure and the mechanical properties of its elementary components. Firstly, we reconstruct the linear relation between the clinically accessible grey values making up a CT, and the X-ray attenuation coefficients quantifying the intensity losses from which the image is actually reconstructed. Therefore, we combine X-ray attenuation averaging at different length scales and over different tissues, with recently identified 'universal' composition characteristics of the latter. This gives access to both the normally non-disclosed X-ray energy employed in the CT-device and to in vivo patient-specific and location-specific bone composition variables, such as voxel-specific mass density, as well as collagen and mineral contents. The latter feed an experimentally validated multiscale elastoplastic model based on the hierarchical organization of bone. Corresponding elasticity maps across the organ enter a finite element simulation of a typical load case, and the resulting stress states are increased in a proportional fashion, so as to check the safety against ultimate material failure. In the young patient investigated, even normal physiological loading is probable to already imply plastic events associated with the hydrated mineral crystals in the bone ultrastructure, while the safety factor against failure is still as high as five. Copyright © 2016 John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Romane Blanchard
- TU Wien-Vienna University of Technology, Institute for Mechanics of Materials and Structures, Karlsplatz 13/202, Vienna 1040, Austria
| | - Claire Morin
- CIS-EMSE, CNRS:UMR 5307, LGF, Ecole Nationale Supérieure des Mines, Saint-Etienne, F-42023, France
| | - Andrea Malandrino
- Institute for Bioengineering of Catalonia, C/Baldiri Reixac 10-12, Barcelona 08028, Spain
| | - Alain Vella
- Mechanical Engineering Department, University of Malta, Tal Qroqq, Msida MSD, 2080, Malta
| | - Zdenka Sant
- Mechanical Engineering Department, University of Malta, Tal Qroqq, Msida MSD, 2080, Malta
| | - Christian Hellmich
- TU Wien-Vienna University of Technology, Institute for Mechanics of Materials and Structures, Karlsplatz 13/202, Vienna 1040, Austria
| |
Collapse
|
3
|
Oftadeh R, Entezari V, Spörri G, Villa-Camacho JC, Krigbaum H, Strawich E, Graham L, Rey C, Chiu H, Müller R, Hashemi HN, Vaziri A, Nazarian A. Hierarchical analysis and multi-scale modelling of rat cortical and trabecular bone. J R Soc Interface 2016; 12:rsif.2015.0070. [PMID: 25808343 DOI: 10.1098/rsif.2015.0070] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The aim of this study was to explore the hierarchical arrangement of structural properties in cortical and trabecular bone and to determine a mathematical model that accurately predicts the tissue's mechanical properties as a function of these indices. By using a variety of analytical techniques, we were able to characterize the structural and compositional properties of cortical and trabecular bones, as well as to determine the suitable mathematical model to predict the tissue's mechanical properties using a continuum micromechanics approach. Our hierarchical analysis demonstrated that the differences between cortical and trabecular bone reside mainly at the micro- and ultrastructural levels. By gaining a better appreciation of the similarities and differences between the two bone types, we would be able to provide a better assessment and understanding of their individual roles, as well as their contribution to bone health overall.
Collapse
Affiliation(s)
- Ramin Oftadeh
- Center for Advanced Orthopaedic Studies, Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA, USA
| | - Vahid Entezari
- Center for Advanced Orthopaedic Studies, Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Guy Spörri
- Center for Advanced Orthopaedic Studies, Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA Institute for Biomechanics, ETH Zurich, Zurich, Switzerland
| | - Juan C Villa-Camacho
- Center for Advanced Orthopaedic Studies, Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Henry Krigbaum
- Department of Orthopaedics, University of California, San Francisco, CA, USA
| | - Elsa Strawich
- Laboratory for the Study of Skeletal Disorders and Rehabilitation, Boston Children's Hospital, Department of Orthopaedic Surgery, Harvard Medical School, Boston, MA, USA
| | - Lila Graham
- Laboratory for the Study of Skeletal Disorders and Rehabilitation, Boston Children's Hospital, Department of Orthopaedic Surgery, Harvard Medical School, Boston, MA, USA
| | - Christian Rey
- Centre Inter Universitaire de Recherche et d'Ingénierie des Matériaux, Ecole Nationale Supérieure des Ingénieurs en Arts Chimiques et Technologiques, Toulouse, France
| | - Hank Chiu
- Department of Biomedical Engineering, University of Memphis, Memphis, TN, USA
| | - Ralph Müller
- Institute for Biomechanics, ETH Zurich, Zurich, Switzerland
| | - Hamid Nayeb Hashemi
- Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA, USA
| | - Ashkan Vaziri
- Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA, USA
| | - Ara Nazarian
- Center for Advanced Orthopaedic Studies, Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| |
Collapse
|