Mattus, Catherine H. | Search NASA

DOE OSTI2020

High-performance concrete mix for precast wythes

A lightweight concrete composition includes the concrete components, per yd3 of concrete: Type III Portland cement (lb/yd3) 200-900; metakaolin (lb/yd3) 100-520; calcium sulfoaluminate cement (CSA) (lb/yd3) 40-840; 3/8″ lightweight expanded slate aggregate (lb/yd3) 70-550; lightweight fine expanded slate aggregate (lb/yd3) 300-550; expanded glass fine aggregate (0.5-1 mm) 35-90 (lb/yd3); expanded glass fine aggregate (1-2 mm) 35-90 (lb/yd3); water (lb/yd3) 300-350; CSA cement set retarder 0.015 to 0.06 oz per lb of CSA cement; high-range water-reducing admixture 120-1000 (fl. oz/yd3); hydration controlling admixture 0-80 (fl. oz/yd3); reinforcing non-metallic lightweight fibers <1.5″ in length 0-8 (lb/yd3); wherein the concrete has a flexural strength of at least 600 psi at 12 hours, a density of 95 to 110 lb/ft3, and a compressive strength at 28 days of at least 7,000 psi. A lightweight concrete wythe and method of making a lightweight concrete wythe are also disclosed.

Hun, Diana E.↗

DOE OSTI2020

Cement having stress-indicating properties

A system and method measures subterranean stress. The system and method includes a cement mixture that is mixed with water to set as a solid and a stress measuring-medium having piezospectroscopic properties that directly reveals stress in situ within the cement mixture in response to a photo stimulation. The stress measuring-medium combines with the cement mixture as a dry blend before being combined with water.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Development and Characterization of 3D-Printed Cementitious Sytems for Innovative Nuclear Systems

The Transformational Challenge Reactor (TCR) is being developed to demonstrate a revolutionary approach to deploying new nuclear power systems by building and operating an additively manufactured microreactor. This initiative provides a unique opportunity to investigate the possibility of taking advantage of the recent development of the 3D-printed concrete system using the Sky Big Area Additive Manufacturing (SkyBAAM) printer at the Manufacturing Demonstration Facility (MDF) at Oak Ridge National Laboratory. Two pathways have been pursued in parallel since the end of the second quarter of FY19: 1. Development of methods to characterize the performance of additive manufacturing concrete using traditional Portland-cement based solution, and 2. Investigation of the opportunity to develop innovation of printable materials with higher irradiation-resistance performance using nontraditional concrete solutions in favor of carbonated cementitious materials (CCMs). This report describes the results achieved to date for both pathways. The main results are listed below: 1. A test protocol has been established to characterize the fracture properties of 3D-printed concrete; this protocol will be used to assess the performance of printed traditional and nontraditional cementitious materials, with a focus on performance of the interfaces inherent to the additive manufacturing process. 2. A state-of-the-art review of the mechanisms, fabrication method, and performance of CCMs was conducted. CCMs appear to be a viable, highly innovative, more performant alternative to Portland-based cementitious solution for the erection of biological shield pending some materials development.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗