Is this project an undergraduate, graduate, or faculty project?
Undergraduate
group
What campus are you from?
Daytona Beach
Authors' Class Standing
Keenan Hubbard, Senior
Lead Presenter's Name
Keenan Hubbard
Faculty Mentor Name
Ghana Ellithy
Abstract
Geogrids have been a longstanding method to enhance performance in roadway construction. This research project aims to explore the behavior of composite pavement sections under cyclic triaxial testing, with a specific focus on measuring local strains. To evaluate the impact of geogrids on roadways performance, six cyclic triaxial tests will be conducted with and without the use of geogrid reinforcement. The composite sample is 50 mm in diameter, 300 mm of height, the lower section of each sample is a mix of bentonite clay and sand simulating the subgrade layer, while the upper section consists of aggregate material to simulate the base course. Between these two layers, a geogrid layer will be placed to improve the structural stability and load distribution of the roadway section. The base layer thickness will measure 50 mm, while the remaining 250 mm of the sample will consist of the subgrade varying in strength at 1%, 2%, and 4% California Bearing Ratio (CBR). For each subgrade CBR, a sample will be tested with and without geogrid bring the total number of tests to six. The cyclic triaxial test measures an average strain for the whole 300 mm sample. In this work, strain gauges will be placed above and below the geogrid layer. The strengthening of the geogrid- reinforced base layer is mainly due to interlocking of the aggregate within the geogrid apertures. By comparing local strains of the base and subgrade layers to the average strain, the role of reinforcement could be quantified and better understood. This research work aims to advance the comprehension of composite pavement behavior under cyclic loading conditions.
Keywords: Geogrids, Cyclic Triaxial, CBR, Local Strain, Total Strain, Strain Gauges, Composite Section
Did this research project receive funding support from the Office of Undergraduate Research.
Yes, Student Internal Grant
Using Strain Gauges to Measure Local Strain in Cyclic Triaxial Testing
Geogrids have been a longstanding method to enhance performance in roadway construction. This research project aims to explore the behavior of composite pavement sections under cyclic triaxial testing, with a specific focus on measuring local strains. To evaluate the impact of geogrids on roadways performance, six cyclic triaxial tests will be conducted with and without the use of geogrid reinforcement. The composite sample is 50 mm in diameter, 300 mm of height, the lower section of each sample is a mix of bentonite clay and sand simulating the subgrade layer, while the upper section consists of aggregate material to simulate the base course. Between these two layers, a geogrid layer will be placed to improve the structural stability and load distribution of the roadway section. The base layer thickness will measure 50 mm, while the remaining 250 mm of the sample will consist of the subgrade varying in strength at 1%, 2%, and 4% California Bearing Ratio (CBR). For each subgrade CBR, a sample will be tested with and without geogrid bring the total number of tests to six. The cyclic triaxial test measures an average strain for the whole 300 mm sample. In this work, strain gauges will be placed above and below the geogrid layer. The strengthening of the geogrid- reinforced base layer is mainly due to interlocking of the aggregate within the geogrid apertures. By comparing local strains of the base and subgrade layers to the average strain, the role of reinforcement could be quantified and better understood. This research work aims to advance the comprehension of composite pavement behavior under cyclic loading conditions.
Keywords: Geogrids, Cyclic Triaxial, CBR, Local Strain, Total Strain, Strain Gauges, Composite Section