The focus of this study was to determine the feasibility of using kaolin, a very small particle clay, as partial replacement of fine aggregates in Portland cement concrete (PCC). Kaolin clay is a locally available (Macon, GA, USA) and inexpensive clay mineral. The product, KaMin 90©, used has an average particle size of 1.5 microns and has a low embodied energy. The slump, air void content and compressive strength were examined on samples of PCC with different % of Kaolin. This research indicated the maximum kaolin substitution of fine aggregate for workability. An optimal dosage range for PCC cylinder compressive strength was also defined and found to be 33% greater than the control group. It was also noted that Kaolin engenders a soft and cohesive concrete mix that prevents segregation. A brief cost analyses was performed and determined the economic feasibility of Kaolin PCC.
The objective of this research was to investigate the influence of WMA additives on the properties of WMA binders through a series of laboratory testing such as viscosity, penetration, ductility, and softening points on the binders. The experimental design included the use of three WMA additives of Sasobit, Rediset, and Evotherm at a recommended content of 2, 2 and 0.6% respectively, two base binder sources, and one modified binder sources. The properties of WMA binders were compared to those of original asphalts without the additives as controls. Results from this study showed that: (1) Three WMA additives of Sasobit, Evotherm and Rediset increased the dynamic viscosity (60°C) of asphalt binders; (2) The additives of Evotherm and Rediset reduced the kinematic viscosity (130°C) of tested WMA asphalt binders. Adding 2 % Sasobit did not affect the kinematic viscosity; (3) Adding 2 % Sasobit reduced the penetration of WMA asphalt binder obviously. The most reduced rate of penetration is 22.7 % for SK base asphalt binder; (4) The WMA additives increased the softening point of WMA asphalt binders, except for the case with 0.6 % Evotherm. The effect of adding 2% Sasobit on the softening point of asphalt binders is the most significant, while the effect of adding 0.6 % Evotherm is the least; (5) adding 0.6 % Evotherm increased the ductility of warm asphalt binders by 28.6 %, while adding 2 % Sasobit reduced the ductility of warm asphalt binders obviously.
The objective of this study was to evaluate the effect of nano-sized hydrated lime on the moisture susceptibility of the hot mix asphalt (HMA) mixtures in terms of three methodologies to introduce into the mixtures. The experimental design for this study included the utilizations of one binder source (PG 64-22), three aggregate sources and three different methods introducing the lime. A total of 12 types of HMA mixtures and 72 specimens were fabricated and tested in this study. The performed properties include indirect tensile strength (ITS), tensile strength ratio (TSR), flow, and toughness. The results indicated that the nano-sized lime exhibits better moisture resistance. Introducing process of the nano-sized lime will produce difference in moisture susceptibility.
The objective of this research was to investigate the influence of Warm Mix Asphalt (WMA) additives on asphalt mixture properties through the laboratory testing programs such as air voids, tensile strength ratio (TSR), dynamic stability, and low temperature bending failure strain tests. The experimental design included the use of three WMA additives of Sasobit, Evotherm and Rediset, one base (unmodified) binder source, and one modified binder source. The WMA mixtures were compared to those of controls, i.e., mixtures without the additives. Results from this study showed that: (1) WMA mixtures with Rediset, Evotherm, and Sasobit had slightly higher air voids than Hot Mix Asphalt (HMA); (2) All WMA mixtures with SBS modified asphalt have lower TSR values than the original ones. The TSR of the WMA mixtures with base (unmodified) asphalt is not significantly different from HMA; (3) The WMA mixtures with SBS modified asphalt have lower values of the dynamic stability and bending failure strain than HMA, while the WMA mixtures with base asphalt are contrary, except with Rediset additives.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.