Engineering Commons^™

Effect Of Recycled Concrete Aggregates On The Long-Term, Elastic, Total Deflection And Strength Of Precast Prestressed Hollow Core Concrete Slabs, Lizeth Marisol Gomez Santana

Civil Engineering Theses

Concrete constitutes the largest portion of construction and demolition waste generated each year in the United States. The Environmental Protection Agency (EPA) estimates that the total production of construction and demolition of concrete waste during 2015 was 381.8 million tons. In order to reduce the economic and environmental effects of waste concrete, researchers have begun to incorporate it into concrete mixtures. However, the inherent variability in mechanical properties between RCA sources makes it difficult to quantify the maximum permissible replacement of natural aggregate and the end-result properties of concrete. This project investigates the use of recycled concrete aggregates (RCA) obtained …

Experimental Investigation Of Whitmore Section And Block Shear Failures In Steel Gusset Plates Using Digital Image Correlation, Prajwal Pokhrel

Civil Engineering Theses

Gusset plates are necessary for transferring loads from one structural member to another. During load transfer gussets can undergo shear, net section rupture and gross section yielding. Gusset design is a complex process and there is still a lack of knowledge regarding the stress and strain distribution in gusset plates. Current design practices which use Whitmore method, may not be sufficient to accurately predict the capacity of a gusset plate. An experimental study was conducted at The University of Texas at Tyler to understand the failure mechanism of gusset plates under uniaxial tensile loading. Variables considered for the experiment are …

In-Situ Field Monitoring Of A Uhpc And Hpc Bridge Superstructure Under Diagnostic Load Testing Using Digital Image Correlation, Prajwol Sharma

Civil Engineering Theses

New innovative methods of bridge design are being sought to increase the service life of these structure. High Performance Concrete (HPC) and Ultra-High-Performance Concrete (UHPC) utilizes a mix of high strength concrete with steel fibers to create a strong and ductile reinforced concrete mix. While not new to civil engineering construction, this material still has some uncertainty of its performance both long and short term. As a result, in-situ experimental monitoring is important to verify methods of design and the suitability of the materials. A two-span pre-stressed UHPC and HPC reinforced concrete bridge superstructure was designed at New Mexico State …

Experimental Investigation Of Adobe Structures With Digital Image Correlation, Ashmita Wasti

Civil Engineering Theses

Adobe brick (or Mudbrick) is commonly used as a construction material for residential structures in the Southwest portion of the United States. Adobe bricks are formed from mud that is composed of sand, silt, clay and water that is further mixed with straw then allowed to dry in the open environment. The straw aids in providing reinforcement for the brick and helping the brick dry more evenly which in turn reduces the amount of shrinkage cracks. The final product is a strong, durable, heavy brick used in the construction of homes. While this practice of adobe brick construction has been …

Seismic Performance Of Earth Slopes Subjected To Earthquake Mainshock – Aftershock Sequences, Alisha Khanal

Civil Engineering Theses

Mainshocks are usually followed by aftershocks. Aftershocks continue over a period of time with a decreasing frequency and there is not sufficient time for repair and retrofit between a mainshock – aftershock sequence. Typically, aftershocks are smaller in magnitude; however, aftershock ground motion characteristics such as the intensity and duration can be greater than the mainshock due to the changes in the earthquake mechanism and location with respect to the site. The seismic performance of slopes is typically evaluated based on the sliding displacement predicted to occur along a critical sliding surface. Various empirical models are available that predict sliding …

Laboratory Evaluation And Neural Network Modeling For Rotational Viscosity Of Reacted And Activated Rubber Modified Binders, Mayzan Isied

Civil Engineering Theses

Crumb rubber surface activation and pretreatment are considered as one of the promising newly introduced methods for asphalt rubber production. Reacted and Activated Rubber (RAR) is an elastomeric asphalt extender produced by the hot blending and activation of crumb rubber with asphalt and Activated Mineral Binder Stabilizer (AMBS). Besides RAR ability in enhancing the performance of asphaltic mixtures, its dry granulate industrial form enabled its addition directly into the mixture utilizing pugmill or the dryer drum with very minimal to no modification required on the plant level.

This study aims to evaluate the rotational viscosity of RAR modified binders and …