Penilaian mikrostruktural bahan-bahan simen kompleks telah dimungkinkan oleh pencitraan mikroskopik seperti Mikroskop Pengimbasan Elektron (SEM) dan Mikroanalisis X-Ray. Khususnya, penggunaan pengimejan SEM konkrit dan analisis imej digital telah menjadi biasa dalam analisis dan pemetaan teknologi konkrit sama ada secara kualitatif atau kuantitatif. Dalam kajian ini, enam sampel imej SEM dua dimensi (2D) telah diubah secara spasi dengan menggunakan proses resampling standard untuk menghasilkan imej sampel SEM Geo-rujukan. Selepas itu, imej-imej SEM yang diletak semula ini dianalisis dan plot histogram intensiti dihasilkan untuk memudahkan penafsiran visual. Analisis imej digital yang dilakukan kemudiannya adalah proses penambahbaikan dan pengenyahbunyi yang menggunakan dua kaedah penapisan iaitu penapis median dan penapis penyesuaian kotak. Imej yang ditapis semula, seterusnya menjalani proses pengklasifikasian K-Means yang tidak diselia untuk memisahkan setiap piksel individu secara berasingan sepadan dengan data spektrum. Dengan segmen spasial algoritma K-Means, kumpulan kluster yang dihasilkan telah dikaji dengan teliti sebelum meneruskan analisis terakhir. Dari data yang dihasilkan, pemetaan pengagihan ruang k-cluster dan kuantifikasi retak mikro (lompang) dilakukan. Hasil akhir gambar SEM (sampel 1 hingga 4) memperlihatkan peratusan data k-cluster yang lebih tinggi yang menunjukkan korelasi yang baik dengan komposisi unsur utama analisis EDX, iaitu Oksida (O), Silikon (Si) dan Karbon (C). Sementara itu, penilaian visual subjektif sampel imej 5 dan 6 telah mengesahkan perkembangan retak mikro pada imej SEM konkrit di mana ketumpatan retak adalah 3.02% dan 1.30%, masing-masing.
_______________________________________________________________________________________________________
The microstructural evaluation of complex cementitious materials has been made possible by the microscopic imaging tools such as Scanning Electron Microscope (SEM) and X-Ray Microanalysis. Particularly, the application of concrete SEM imaging and digital image analysis have become common in the analysis and mapping of concrete technology either in the qualitative or quantitative manner. In this study, six samples of two-dimensional (2D) SEM images were spatially transformed using the standard resampling process to produce Geo-referenced SEM sample images. Subsequently, these resampled SEM images were analysed and the intensity histogram plot was produced to facilitate visual interpretation. The consecutive digital image analysis performed was the enhancement and noise removal process using two filtering methods i.e. median and adaptive box filter. The filtered resampled images, then undergone the unsupervised K-Means classification process to collectively separate each individual pixel corresponds to the spectral data. By spatial segmentation of K-Means algorithms, the cluster groups generated were carefully reviewed before proceeding to the final analysis. From the resulting data, the mapping of the spatial distribution of k-cluster and the quantification of micro-cracks (voids) were performed. The final results of the SEM images (sample 1 to 4) showed higher percentage of k-cluster data indicating a good correlation with the major elemental composition of EDX analysis, namely Oxide (O), Silicon (Si) and Carbon (C). Meanwhile, the subjective visual assessment of the image sample 5 and 6 has confirmed the micro-crack developments on the concrete SEM images upon which the crack density was 3.02 % and 1.30 %, respectively.
Quantitative analysis and mapping of concrete scanning electron microscope (sem) images / Elly Nur Myaisara Maizul