Faculty Publications

Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736

Publications by NITK Faculty

Browse

Subject: search.filters.subject.Binder content

Search Results

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    Evaluation of properties of porous friction course mixes for different gyration levels
    (2009) Suresha, S.N.; George, V.; Shankar, A.U.R.
    Porous frictions courses (PFCs) are characterized by high percent air voids content, and are widely used as pavement surface drainage layers. This paper presents details on the laboratory investigation performed on evaluation of properties of PFC mixes using the Superpave gyratory compactor. It also, provides a brief review of the latest specifications related to standard practices for mix design and the uses of these mixes adopted by various agencies. Major differences were observed in the design gyrations (Ndesign) and the design aggregate gradations. In this study, six gradations (G) were investigated with binder contents (BCs) ranging between 4.0 and 5.0% by mass of the total mix, for various gyration levels (N). The effect of N, G, and BC on the volumetric properties, unaged abrasion loss, permeability, and the permanent deformation characteristics of PFC mixes were investigated. The experimental results were statistically analyzed to identify the major influencing factors and their significance. © 2009 ASCE.
  • No Thumbnail Available
    Item
    Multi-objective optimization of one-part geopolymer mortars adopting response surface method
    (Elsevier Ltd, 2023) Srinivasa, A.S.; Yaragal, S.C.; Swaminathan, K.; Rakesh Kumar Reddy, R.
    One-part geopolymers have immense potential in large-scale structures owing to their improved safety and convenience of handling over the conventional geopolymer mixing procedure. Thus, this study aims at optimizing the mixes by assessing the influence of binder content, activator dosage and water to geopolymer solids (W/GS) ratio on the flowability, strength, and shrinkage properties of one-part geopolymer mortars (OPGM). The test results were utilized to develop models that could predict the desired properties of mixes and optimize the mix proportions of OPGMs using the response surface method. The fly ash and slag-based OPGMs were developed. The GGBS substitution was chosen as 25, 50, and 75% by volume of fly ash. The activator dosage was taken as 8, 12, and 16% by mass of total binder content at varied W/GS ratios of 0.35, 0.40, and 0.45. The responses considered were flowability, compressive and flexural strengths at 7 and 28 days, and drying shrinkage of up to 180 days. Total of 504 specimen were cast to record the observations for this optimization study. The GGBS content, W/GS ratio, and combined effect of these factors were found to be the most influential factors affecting the responses. The optimal mix proportion obtained consists of 49.8% GGBS, 13.6% activator dosage, and 0.37 W/GS ratio. This mix achieved 170.4 mm flow, 57.8 MPa and 5.9 MPa compressive and flexural strengths, respectively and also 1626 microstrain of 180 days drying shrinkage. The microstructural characterization adopting techniques like SEM, XRD, TGA and FTIR was carried out to study microstructural changes, mineral phases, thermal mass loss and molecular bonding of OPGM mixes. This study revealed that mix with 50% GGBS, 12% activator dosage and 0.40 W/GS ratio can better be characterized compared to other mixes. © 2023 Elsevier Ltd
  • No Thumbnail Available
    Item
    Properties of Rejuvenated Reclaimed Asphalt Pavement Mixtures with Waste Glass Powder and Sisal Fibers for Pavements
    (American Society of Civil Engineers (ASCE), 2025) Marathe, S.; Akarsh, A.P.; Bhat, A.K.
    By exploring the usage of reclaimed asphalt pavement (RAP) mixtures in pavement construction, this study fills a substantial gap in the literature. The research includes a number of experimental investigations ranging from enhancing binder qualities to efficiently using waste engine oil (WEO) as a rejuvenator, as well as detailed performance evaluations using waste glass in powdered form. RAP materials were meticulously graded to provide stone matrix asphalt compositions. Throughout the study, a reinforcing supplement of 0.30% sisal fiber was utilized. The determination of optimal (fresh) binder content (OBC) of 3.50% and the selection of a lowered OBC of 2.50% with the adding of 20% WEO rejuvenator are among the preliminary key results. The study also effectively modified RAP mixes by including waste glass powder (WGP) as a mineral additive, yielding an optimal dose of 5.0% for a selected RAP mix. Performance testing on the improved RAP mixtures produced remarkable results. The Marshall stability value was increased by 20% with 5.0% WGP content. The Marshall quotient constantly fell between 2 and 5 kN=mm, which is the desired range. Tensile strength ratios often crossed 80%, and the drain-down potential was decreased by the use of WGP drastically. The combination with a 5.0% WGP content excelled the control mixture in rutting and fatigue testing and had a maximum retained Marshall stability of 93.1%. Additionally, pavement design utilizing Indian Roads Congress criteria demonstrated the viability of building pavements for low-volume roads using RAP mixtures in an efficient and sustainable manner. This study highlights the utilization of RAP to achieve sustainability in pavement building, offering a viable approach to bituminous pavement rehabilitation. © 2024 American Society of Civil Engineers.