Date of Award
8-2024
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Civil Engineering
Committee Chair/Advisor
Dr. Prasad Rangaraju
Committee Member
Dr. Jennifer Ogle
Committee Member
Dr. Fabricio Leiva
Committee Member
Dr. Vincent Bongioanni
Abstract
High Friction Surface Treatment (HFST) is a proven technology to reduce crashes on roadways by increasing the coefficient of friction between vehicle tires and the pavement. However, it is an expensive solution due to the high cost of the two commonly used constituent materials, calcined bauxite aggregate and epoxy resin binders.
This study evaluated the abrasion resistance performance of four alternative HFST aggregates to calcined bauxite using Los Angeles Abrasion and Micro-Deval Abrasion tests, and studied the surface texture utilizing a high-resolution laser scanner and friction utilizing the British Pendulum Test.
This study also assessed the performance of non-proprietary Ultra High-Performance Concrete (UHPC) for use as an alternative to epoxy resins in HFST application. In this regard, the flow, setting behavior, bond strength, abrasion resistance, compressive strength and drying shrinkage of the UHPC mixtures were assessed. Additionally, the effects of intermixing calcined bauxite aggregate in UHPC at varying contents on the performance of UHPC were evaluated.
Furthermore, this study developed and evaluated various application methodologies for UHPC based HFST surfaces including the use of UHPC with intermixed aggregate where surface retarders were used to expose the aggregate. Other methods included broadcasting the aggregate onto the UHPC binder and embedding under self-weight or with the use of vibration to improve embedment. Effects of aggregate moisture content and UHPC water content were also evaluated. The performance of UHPC based surfaces was evaluated by the British Pendulum Test and the Dynamic Friction Tester for friction, a high-resolution laser scanner for texture, and outflow meter for drainage. Polishing was conducted using a Three Wheel Polishing Device and the effects of polishing on friction and texture across selected surface types were evaluated.
The experiments revealed that while two alternative aggregates among the four aggregates were able to provide seemingly good abrasion resistance and initially high levels of friction with adequate texture, under polishing the friction was greatly reduced. Therefore, none of the alternative aggregates tested can be recommended for long term frictional performance, and calcined bauxite remains the premier reliable choice.
Evaluation of UHPC mixtures showed that a UHPC mix could provide adequate bond strength, compressive strength and flow for use as an HFST binder. The bond performance of resin binders exceeded that of UHPC, particularly on asphalt substrates. Calcined bauxite to cementitious materials ratio between 1.5 and 2.0 by mass showed the best performance across various properties of UHPC for application in HFST.
Vibration was shown to improve aggregate embedment in UHPC mixtures, overcoming the poor embedment observed when broadcasting on UHPC with low water content. Based on the potential effects of aggregate moisture content on the properties of UHPC, it is recommended that only oven-dry aggregate be used in UHPC for HFST application.
UHPC based HFSTs with calcined bauxite aggregate were able to produce acceptable levels of friction and texture and maintain the performance under polishing such that they can be categorized as HFST. However, resin-based surfaces with calcined bauxite were superior across testing and provided a more consistent surface. As a proof of concept, UHPC is a viable alternative to epoxy resins for use as an HFST binder with calcined bauxite aggregate. Field scale evaluation is warranted to verify the findings from this lab study.
Recommended Citation
Maeger, Kyle, "Ultra High-Performance Concrete As a High Friction Surface Treatment for Pavements and Bridges" (2024). All Dissertations. 3671.
https://open.clemson.edu/all_dissertations/3671