Engineering Commons^™

Improve The Prediction Of Camber, Deflection, And Prestress Losses In Precast, Prestressed Concrete Bridge Girders, Ahmed Ali Hussein Al Mohammedi

Graduate Theses and Dissertations

Many precast, prestressed concrete girders have camber less or higher than the design values. This discrepancy between the design and the actual camber creates construction problems when installing the cast-in-place concrete deck. The objective of this research was to improve the accuracy of estimating long-term camber, deflection, and prestress losses of precast, prestressed concrete girders.

The experimental program consisted of measuring concrete properties and performing field measurements of camber, deflection, and prestress losses for girders in Arkansas. The investigation involved testing nine full-scale girders from two prestressed concrete plants that regularly supply concrete girders to bridge projects in Arkansas. The …

Material Property Heterogeneity In Dimensional Lumber And Its Relationship To Mass Timber Performance, Fiona O'Donnell

Doctoral Dissertations

According to the Environmental Protection Agency, buildings account for 38% of the United States' carbon dioxide emissions, providing architects and structural engineers a unique opportunity to mitigate a significant factor driving climate change by implementing innovative and sustainable technology in infrastructure design. Wood and mass timber products are becoming an increasingly popular alternative building material due to their economic and environmental benefits. The natural growth of wood leads to highly heterogeneous material properties. Defects such as checks, knots, and localized slope of grain contribute to some of this variation; however, wood properties vary significantly even in clear wood. Using mass …

Evaluation Of Masonry Materials And Structures Using Digital Image Correlation, Brittany Bullard

Civil Engineering Theses

Masonry structures are common throughout the world. Adobe is a masonry material found in the southwestern states of the United States in residential structures. Adobe is mostly used in brick form, where locally collected sand, clay, and silt are combined with natural fibers and water to create unfired bricks. The natural fibers provide the primary reinforcement of these bricks, and aid in the drying process, helping the bricks dry evenly. While this material has been used as a residential building material for many hundreds of years, much is still not understood regarding its mechanical properties, as they are dependent on …