KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Settings

Author: search.filters.author.Chaiyaput, SalisaSubject: search.filters.subject.Microstructure

Search Results

Now showing 1 - 3 of 3
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Item,
    Utilization of ladle furnace slag and fly ash as partially replacement of cement
    (2025-03-01)
    Thwe, Khin Sam
    ;
    Ayawanna, Jiratchaya
    ;
    Mase, Lindung Zalbuin
    ;
    Chaiyaput, Salisa
    Ladle Furnace Slag (LFS) and fly ash (FA) are industrial waste products commonly deposited in landfills, while the cement industry is a major source of carbon dioxide (CO<inf>2</inf>) emissions. Previous research has explored using LFS and FA as cement replacement materials to help mitigate environmental impacts. Yet, no studies have explored combining LFS and FA as cement replacement materials. Therefore, this research highlights the study of the combination of LFS and FA mixes as a partial cement replacement. The mix design for cement replacement materials was developed by combining ordinary Portland cement (OPC), LFS, and FA in the following weight ratios: 10:10:80, 20:20:60, and 30:30:40. These mix designs were assessed in comparison to 100%OPC (% by weight), evaluating key properties (bulk density, specific gravity, normal consistency, setting time, compressive strength, flexural strength, and microstructural characteristics). According to the findings, incorporating LFS and FA, both pozzolanic materials effectively improved the strength of the material by promoting a pozzolanic reaction, particularly during the final stages of curing. Furthermore, it was found that a mixed design containing 20% OPC, 20% LFS, and 60% FA demonstrated suitable properties for cement replacement in various applications, with beneficial results in terms of setting time and strength development. From X-ray fluorescence (XRF) and scanning electron microscope (SEM analysis), C-S-H gel, as well as Ca(OH)<inf>2</inf> and Mg(OH)<inf>2</inf> chemical compounds, were formulated. The aforementioned replacement is being used to promote environmental sustainability through the efficient use of industrial byproducts.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Item,
    Microstructure investigation of soft clay after a vacuum PVD second improvement: a case study in Bangkok area Thailand
    (2023-10-01)
    Chaiyaput, Salisa
    ;
    Kotkhangphlu, Pornsuda
    ;
    Chao, Kuo Chieh
    ;
    Chanin, Chatchai
    ;
    Ayawanna, Jiratchaya
    This study first demonstrates the microstructural changes of soft Bangkok clay at a real construction site following vacuum PVD modification of soft clay at a − 9-m elevation obtained from Thailand’s Suvarnabhumi Airport. In contrast to the undisturbed soil and the first-improvement soil, the second vacuum PVD improvement transformed the face-to-face orientation of the soil structure into edge-to-face flocculated particles. This approach also greatly affected the inorganic NaCl salts leaching from the pore water, resulting in stronger bonding with less soil permeability and an improved consolidation of soil structure. The repulsive interactions between the soil particles lowered the average liquid limit and plastic limit values, which contributed to the edge-to-face flocculation of the soil particles and greatly increased the shear strength. Vacuum PVD with a second improvement is a highly effective solution for raising the settlement rate and minimizing the settlement time to improve soft clay with low strength and high compressibility.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Item,
    Destructive and nondestructive characteristics of solidified reservoir sediments incorporating microstructural analyses
    (2022-08-01)
    Jamsawang, Pitthaya
    ;
    Poorahong, Hatairat
    ;
    Jongpradist, Pornkasem
    ;
    Likitlersuang, Suched
    ;
    Chaiyaput, Salisa
    Reservoir sediments create a range of severe problems for hydropower dams. Although reservoir sediments can be excavated, nonetheless, sizeable dumping lands for such excavated sediments are unavailable at this time. This paper presents an experimental investigation of the destructive and nondestructive properties and microstructural characteristics of reservoir sediments solidified with fly ash–cement blend for reuse as construction materials. The obtained natural sediment was classified as well-graded sand with silt. The destructive experiments comprised unconfined compression, indirect tension, California bearing ratio, resilient modulus, and durability against wet–dry cycle tests, while the nondestructive experiments included a free–free resonance test. Microstructural investigations consisting of X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, and energy-dispersive X-ray spectrometry were performed to verify the macroscale test results. The results showed that fly ash–cement blend exhibited increased strength values on the order of 2 to 9 times that of unsolidified sediments. Using fly ash-blended cement was more effective than using sole cement or sole fly ash, and mixtures with 10% fly ash delivered the best strength and modulus values. Various functional empirical correlations were proposed. Utilizing six wet–dry cycles is acceptable because the strength of the samples subjected to the six wet–dry cycles was lower than the given value. The results of the peak intensities of calcium silicate hydrate, mass losses, calcium contents, and scanning electron microscopy images derived from the microstructural investigations confirmed the macroscale test results.