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Jay Goguen, Andrew Sharits, Ann Chiaramonti Debay, Thomas V. Lafarge, Edward Garboczi
Samples of soils collected by the Apollo 11 mission (10084) and the Apollo 14 mission (14163) were obtained from the NASA CAPTEM program. The particle size, shape, and internal porosity were characterized in three dimensions (3D) using a combination of X
Edward Garboczi, Peng Gao, Juan Wu, Peiyun Qiu, Jingzhe Li, Hongjie Liu, Zhiwei Qian, Jiangziong Wei, Qijun Yu
The spherical harmonic (SH) series have been widely used in recent years to reconstruct three-dimensional (3D) particle shape for reducing the memory requirements of morphological data and facilitating the calculation of various particle shape parameters
Howie Joress, Rachel Cook, Austin McDannald, Mark Kozdras, Jason hattrick-simpers, Aron Newman, Scott Jones
Despite the long history of cement and concrete, there are still large gaps in fundamental knowledge of their properties development. The dire need for improved cementitious repair materials, requires a revolution in the way they are formulated and tested
Retrofit and repair of structures occur under differing circumstances but are both necessary to improve existing building stock and increase resilience of communities against hazards. FRP is an attractive option for both retrofit and repair because of its
Portlandite (calcium hydroxide: CH: Ca(OH)2) suspensions aggregate spontaneously and form percolated fractal aggregate networks when dispersed in water. As a result, the yield stress and viscosity of portlandite suspensions diverge at low particle loadings
Edward Garboczi, Kai Lyu, Yufeng Gao, Changwen Miao, Xiaoyan Liu
Compared with overall air void content and size distribution, the spatial arrangement of air voids is probably of more importance in the durability of cement-based materials subjected to repeated freeze-thaw cycles. In this paper, using X-ray computed
Edward Garboczi, Mohammad Balapour, Thiha Thway, Grace Hsuan, Yaghoob Farnam, Newell Moser
This study characterizes the engineering properties of lightweight aggregate (LWA) manufactured from low calcium (F-FA) and high calcium (C-FA) waste fly ash that were designed using a previously-developed thermodynamics-guided process. LWA properties that
Edward Garboczi, Mohammad Balapour, Mohammad Khaneghahi, Yick Hsuan, Diana Hun, Yaghoob Farnam
In this study, an off-spec fly ash-based spherical lightweight aggregate (LWA), designated SPoRA, was manufactured through a pilot-scale production and its engineering properties, including specific gravity, dry rodded unit weight, water absorption
Edward Garboczi, Sharu Kandy, Iman Mehdipour, Narayanan Neithalath, Aditya Kumar, Mathieu Bauchy, Samanvaya Srivastava, Torben Gaedt, Gaurav Sant
Extrusion-based 3D printing with rapidly hardening polymeric materials is capable of building almost any conceivable structure. However, concrete, one of the most widely used materials for large-scale structural components, is generally based on inorganic
Pavitra Murrua, Christa Torrence, Zachary Grasley, KR Rajagopal, P Alagappan, Edward Garboczi
Damage in concrete has been modeled using various approaches such as fracture mechanics, continuum damage mechanics and failure envelope theories. This study proposes a new theory to model damage in concrete that addresses the limitations associated with
Edward Garboczi, Kai Lyu, Yufeng Gao, Changwen Miao
The air void network, as part of the pore structure of cement-based materials, controls their freeze- thaw durability. Precisely determining the characteristics of the air void system is important in material design and freeze-thaw durability evaluation
Edward Garboczi, Newell Moser, Joseph Biernacki, Hajar Afarani, Ebrahim Esfahani
Additively manufactured cement-based structures for infrastructure applications suffer from in-construction shape deformations, which are a strong function of process conditions and the rheology of the printing material (cement paste, mortar, or concrete)
Edward Garboczi, Christa Torrence, Zachary Grasley, William Lawrimore
A novel method of detecting overlap between two irregularly shaped virtual particles whose surfaces are described by analytical functions is presented in this study. Utilizing the analytical equation that describes the surface of the particle, the first
Mohammad Balapour, Thiha Thway, Rathin Rao, Grace Hsuan, Yaghoob Franam, Newell Moser, Edward Garboczi
In this study, a systematic thermodynamics-based framework was applied to recycle waste low and high-calcium coal combustion Fly Ash (FA) into synthetic lightweight aggregates (LWA) through sintering. The process to successfully manufacture synthetic LWA
Edward Garboczi, Jeffrey W. Bullard, Olafur Wallevik, Pierre Estephane
This study follows a first paper written on some three-dimensional geometrical quantities of a selection of sand particles from the United Arab Emirates (UAE), determined using a combination of X-ray microcomputed tomography (µCT) and spherical harmonic
Edward Garboczi, Gopal Mulukutla, Emese Hadnagy, Matthew Fearon
Shape is an important indicator of the physical and chemical behavior of natural and engineered particulate materials (e.g., sediment, sand, rock, volcanic ash). It directly or indirectly affects numerous microscopic and macroscopic geologic, environmental
The measured dissolution rate of a granular medium depends on its surface area and how the surface area changes during the course of the measurement. Moreover, the assumption that the specific surface area either remains constant or initially increases
Fahim H. Sadek, Travis E. Thonstad, Sorin Marcu, Jonathan Weigand, timothy J. barrett, Hai S. Lew, Long Phan, Adam L. Pintar
This report describes the results of Task 1 of a five-task comprehensive research program being conducted at the National Institute of Standards and Technology (NIST) under the sponsorship of the U.S. Nuclear Regulatory Commission (NRC). The overall study
Travis E. Thonstad, Jonathan Weigand, Fahim H. Sadek, Sorin Marcu, timothy J. barrett, Hai S. Lew, Long Phan, Adam L. Pintar
This report describes the results of Task 2 of a five-task comprehensive research program being conducted at the National Institute of Standards and Technology (NIST) under the sponsorship of the U.S. Nuclear Regulatory Commission (NRC). The overall study
Christa Torrence, Aishwarya Baranikumar, Zachary Grasley, Edward Garboczi
Nearly all nuclear power plants in the United States are operating past their intended lifetimes or are requesting lifetime extensions, therefore understanding changes to the concrete containment structure over time is crucial to evaluate the structure's
Edward Garboczi, Christa Torrence, Zachary Grasley, Aishwarya Baranikumar, William Lawrimore
Nearly all nuclear power plants in the United States are operating past their intended lifetimes or are requesting lifetime extensions. Therefore, understanding changes to the concrete containment structure over time is crucial to evaluate the structure's
Edward Garboczi, Hajar Taheri Afarani, William carroll, Joseph J. Biernacki
Cement based pastes for 3D printing applications were prepared using hydrogel-forming polymers. Preliminary results suggest that such gel-forming polymers can reduce the need for more complex admixture packages as printing aids. The influence of polymer