Lesa Brown: Structural Mechanics & Materials Research
1,951 views · Published 20 April 2012 · 2:58 · Indexed 23 October 2026
Channel: Vanderbilt University · 2012 · Education
Vanderbilt University School of Engineering Graduate Student Lesa Brown describes her research in structural mechanics and materials, examining the behavior of carbon nanofiber (CNF) cement composites subjected to accelerated decalcification through exposure to ammonium nitrate. Lesa ia a student in the Department of Civil Engineering at Vanderbilt University School of Engineering, working under the guidance of Dr. Florence Sanchez. Her work includes evaluating the micro-structural and morphological changes within these composites and at the CNF-cement interface to determine the influence of CNFs during decalcification. She is also investigating the behavior and long term durability of CNF cement composites subjected to other chemical weathering forces such as chloride or sulfate solutions. For more information on graduate studies in the department of Civil and Environmental Engineering, visit www.cee.vanderbilt.edu. Lesa also participates in an interdisciplinary research partnership through the Vanderbilt Institute of Nanoscale Science and Engineering (VINSE) which allows students access to additional research equipment on the Vanderbilt campus and encourages interaction between departments. www.vanderbilt.edu/vinse. Research Abstract: Concrete is one of the world's most widely used materials, with applications ranging from infrastructure and water resource management to building structures and hazardous waste containment. Environmental weathering forces play an important role in the sustainability of concrete. These forces can cause micromechanical stresses and cracking which lead to material damage and a decrease in the mechanical properties of the composite. In many cases, the rebar used as tensile reinforcement in the concrete becomes a source of degradation propagation. Carbon nanofibers (CNFs) possess a number of unique properties, including chemical resistance and a high strength-to-weight ratio, which make them an appealing alternative for cement reinforcement at the nano-level. Understanding the interaction between environmental forces, the cement, and the CNFs is vital for the continued viability of using CNFs as a potential nano-reinforcement. The focus of my research is improving the long-term performance and durability of CNF cement composites by examining and understanding the material behavior during exposure to aggressive environments. By investigating the microstructural, morphological, and strength changes as a function of exposure duration, the influence of the CNFs on the micro- and macroscale properties of the material can be determined.
