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High Performance Building Materials |
High Performance Building Materials We are developing a fundamental understanding of the relationship between chemistry, physics, microstructure, performance, and service life of conventional and high-performance concrete and other inorganic building materials. Our goal is to develop tools for predicting the behavior of these materials and their service lifetimes. Because the service life of concrete largely depends on the transport of water, dissolved salts, and gases in the pore system of the concrete, we are developing computational representations of the microstructure of concrete and models to predict its diffusivity, permeability, and sorptivity. We are developing and validating models for simulating microstructure development in cement pastes as the cement hydrates and for simulating the degradation of concrete. We use computational materials science to predict properties like the elastic moduli and rheology of fresh concrete. We also are performing experimental studies on the rheology of concrete in order to improve the design of mixture proportions. We use a variety of techniques including scanning electron microscopy, computerized image analysis, X-ray diffraction and absorption, thermal analysis, and ion chromatography. A synthesis of experimental and computational materials science is being pursued to solve the complex problems that are inherent in a complex material like concrete. This work boosts
the competitiveness of the U.S. construction industry by providing a strong
technical basis for standards for concrete and concrete materials. The
research is coordinated with industry, voluntary standards organizations,
trade associations, the Center for Advanced Cement-Based Materials, and
federal and state government agencies. Contact: Edward Garboczi We are conducting basic and applied research on methods for predicting the performance and service life of organic building materials such as protective coatings for steel and residential housing, caulks and sealants, polymer-matrix composites, and roofing materials. In addition, we are developing a systems approach to advancing the science of appearance measurements for coated objects. We are investigating degradation mechanisms, improving characterization methods, and developing mathematical models for predicting the service life of these materials when they are exposed to their expected in-service environments and subjected to their intended operating conditions. The methodology for making these predictions has a strong basis in reliability theory, and life-testing analysis and the predictive models have a strong basis in the underlying chemistry and physics of degradation. To understand the
mechanisms of degradation and to provide data for models, we are characterizing
materials in many ways, including Fourier transform infrared and UV-visible
spectroscopies, thermal analysis, scanning electron microscopy/energy
dispersive X-ray, and atomic force, and confocal microscopies. We also
are developing improved ways to characterize atmospheric environments
to which these materials are exposed. Characterization of environmental
parameters that cause degradation is required to link material properties
with service life. Our research strengthens the scientific and technical basis for engineering standards for organic building materials developed by voluntary consensus standards organizations. This research is supported by and carried out in close collaboration with industry, universities, and other federal agencies through consortia such as the Coatings Service Life Prediction Consortium and the Polymer Interphases Consortium. Contact: Jonathan W. Martin Construction Materials Reference Laboratories We run the American Society for Testing and Materials (ASTM)-sponsored Cement and Concrete Reference Laboratory (CCRL), founded in 1929, and the American Association of State Highway Transportation Officials-sponsored Materials Reference Laboratory (AMRL), founded in 1965. These laboratories provide a reimbursable, voluntary, quality assurance service for more than 1,200 commercial and other laboratories that test construction materials for compliance with ASTM standards for cements and other concrete materials. We offer laboratory inspections and operate large proficiency sample programs. Contact: James
H. Pielert
Date
created:
April 24, 2002 |