Date of Award
8-2024
Document Type
Thesis
Degree Name
Master of Civil Engineering (MCE)
Department
Civil Engineering
Committee Chair/Advisor
Dr. Prasad Rangaraju
Committee Member
Dr. Fabricio Leiva
Committee Member
Dr. Amir Esmaeilpoursaee
Abstract
High Friction Surface Treatment (HFST) is a roadway remediation technique used to improve pavement’s coefficient of friction, to enhance roadway safety. The application of HFSTs has repeatedly demonstrated the ability to significantly reduce crashes in both wet and dry conditions. Typically, epoxy-resins and calcined bauxite aggregate are used in HFST treatment. However, the high material costs and scarcity of calcined bauxite render this form of HFST an expensive and limited option for roadway rehabilitation. Therefore, the identification of alternative binders and HFST aggregates is needed for broad scale implementation. One potential alternative binder is Ultra-High-Performance Concrete (UHPC), a specialty cementitious material. UHPC is characterized by its high compressive strength (>120 MPa), enhanced toughness, high fluidity, and high bond strength. These properties of UHPC make it a potential alternative to epoxy-resins, however additional research is needed to assess the suitability of UHPC for HFST application. Previous research has shown that compared to natural aggregates, calcined bauxite was found to be a superior aggregate for HFST application, and therefore calcined bauxite will be used as the HFST aggregate in this study.
In this study multiple sets of tests were conducted, to evaluate UHPC-based HFSTs. Initial testing focused on determining suitable materials for UHPC and how varying their inclusion rate impacted performance. From those results, the UHPC mixes were optimized using the Modified Andreasen and Andersen method for particle packing and tested across key HFST failure criteria. This testing provided proof that UHPC-based HFST is possible and identified shrinkage and bond strength as potential modes of failure. After identifying viable mixes, UHPC-based HFST overlays were created and tested under simulated traffic using multiple application methods. This process identified the use of intermixed calcined bauxite in UHPC, followed by the aggregate exposure using set retarders as an effective application method. In addition, the impact of varying intermixed calcined bauxite contents on the properties of UHPC was also studied. The testing on intermixed calcined bauxite contents determined that a calcined bauxite (CB)-to-cementitious materials (CM) ratio of 1.5 to 2.0 provided adequate bond strength while substantially reducing shrinkage. However, the shrinkage reduction was not enough to eliminate the risk of cracking and further testing to evaluate the impact of fibers on shrinkage using the thin-layer shrinkage test was conducted and found a significant increase in strength and a moderate reduction in shrinkage.
Cumulatively, the findings from this study provide general guidelines on how to further develop UHPC-based HFSTs and compare the performance of UHPC-based HFSTs to traditional epoxy-resin-based HFSTs. This study identifies that UHPC-based HFSTs on concrete substrates managed to match or exceed the bond strength of the epoxy-resin-based HFST, whereas the UHPC-based HFST showed an inferior bond strength with asphalt substrate compared to resin-based HFST. Shrinkage mitigation techniques are needed to ensure that shrinkage of UHPC-based HFST does not result in cracking. Finally, it was determined that UHPC with intermixed calcined bauxite aggregate, exposed using set retarders, provided an exceptional frictional performance. Based on the findings from this study, UHPC-based HFST appears feasible, and field studies are warranted to assess long-term performance under true traffic conditions.
Recommended Citation
Biehl, Adam R., "Proportioning and Performance of Ultra-High Performance Concrete (UHPC) for High Friction Surface Treatment (HFST) on Pavement and Bridge Decks" (2024). All Theses. 4378.
https://open.clemson.edu/all_theses/4378
Author ORCID Identifier
0000-0002-3416-1238