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A Collection Of New Studies Using Existing And Proposed Techniques And Instrumentation For Nondestructive Testing And Analysis Of Concrete Materials And Structures, Shane D. Boone
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A variety of studies were performed using existing and newly proposed techniques and instrumentation to further the understanding of nondestructive testing of concrete. A new combined stress wave propagation method was developed that combined the existing methods of the spectral analysis of surface waves, impact echo, and free-free resonant column experimental and analysis techniques. The method was used to determine the stiffness profile and location of embedded voids in a concrete tunnel lining modeled as a three layer concrete slab. A new equation was proposed that predicted the level of damage of concrete samples based on the functions of the …
Quality Evaluation Of Portland Cement Concrete At Early Age With Free-Free Resonant Column, Gilberto Wenglas
Quality Evaluation Of Portland Cement Concrete At Early Age With Free-Free Resonant Column, Gilberto Wenglas
Open Access Theses & Dissertations
At early age, the behavior and mechanical properties of portland cement concrete changes rapidly with time due to hydration. The hydration process consists of a series of chemical reactions that accelerate nonlinearly with the rise in temperature. The hydration process consists of three stages: the dormant period, the setting time, and the hardening time. Timely opening of roads and resumption of constructions depend of the knowledge of these stages. The initial and final setting times are arbitrarily determined by a standard test (ASTM C 403). Although the setting time has been studied for many decades, the new technologies allow making …