PATH: Functionally Graded Cement-Based Materials for Residential Construction

点击翻译按钮获取中文摘要

This research project addresses the production of cement-based materials for residentialconstruction using extrusion so as to produce functionally graded microstructures and thenmeasure and compute the engineering properties provided by such microstructures. The two primary objectives are: to develop construction components (e.g., siding) with graded cellularstructures that are highly porous in the center and dense on the outer surface, thereby reducing thedensity without producing high permeability and low strength usually associated with highlyporous materials and to produce components (e.g., beams) with graded fiberreinforcement such that highest concentration of fibers occurs at the bottom of the beam wherethe tensile strain is greatest, thereby taking advantage of the substantial mechanical benefits offibers in extruded cement-based composites with a lower overall fiber volume through efficientengineering of the microstructure. Co-extrusion of multiple constituents and multiple cycles ofextrusion will be used to process these materials. Specimens will be examined using scanningelectron microscopy to determine whether the processing is producing the desiredmicrostructures. Engineering properties (modulus, Poisson ratio, strength, fracture toughness)will be computed based on microscopic and macroscopic scales. The computed properties will becompared with measured properties and with observed microstructures so as to demonstratevalidity of the computation and to refine the computational method as needed. A relevant broad impact of the proposed research is its potential to increase the use of advancedcement-based materials in residential construction. These materials have important advantagesover the more traditional wood-based materials (fire resistance, durability), however, their use hasbeen limited by their high density and low toughness, issues addressed directly by this research.An industrial advisory group will help assure that the research is suitably innovative, industriallyfeasible, and economically viable The proposed research will also impact education, adding studies of residentialconstruction in the civil engineering curriculum and making studies of construction materialsavailable to students in architecture.