Electronic Theses and Dissertation

Mortar merupakan salah satu material komposit yang telah digunakan sejak masa lampau sebagai bahan perekat dalam konstruksi bangunan. Mortar kuno umumnya tersusun atas bahan pengikat berbasis kapur yang berasal dari batu kapur (CaCO₃) serta agregat seperti pasir yang mengalami proses pengerasan melalui reaksi karbonasi. Penelitian ini bertujuan untuk mengidentifikasi komposisi penyusun mortar kuno pada bangunan bersejarah Mangrove Park Lampulo (MPL) berdasarkan komposisi unsur, fase mineral kristalin, serta gugus fungsi penyusun material. Sampel mortar kuno yang berasal dari tembok pembatas makam kawasan Mangrove Park Lampulo dianalisis menggunakan metode X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD), dan Fourier Transform Infrared Spectroscopy (FTIR). Analisis XRF digunakan untuk menentukan komposisi unsur dan oksida penyusun mortar, XRD digunakan untuk mengidentifikasi fase mineral kristalin, sedangkan FTIR digunakan untuk mengetahui gugus fungsi dan ikatan kimia dalam material. Hasil analisis XRF menunjukkan bahwa unsur utama penyusun mortar kuno adalah kalsium (Ca), silikon (Si), dan oksigen (O), dengan unsur minor lainnya yang berasal dari mineral penyusun agregat dan bahan pengikat. Berdasarkan karakterisasi XRD, mortar kuno didominasi oleh fase mineral kalsit (CaCO₃) dan kuarsa (SiO₂), serta ditemukan fase mineral minor berupa dolomit dan oksida besi. Keberadaan kalsit menunjukkan bahwa material perekat utama berasal dari kapur hasil karbonasi batu kapur, sedangkan kuarsa berasal dari agregat pasir yang digunakan dalam campuran mortar. Analisis FTIR menunjukkan keberadaan gugus fungsi karbonat (CO₃²⁻), silikat (Si–O), serta ikatan Fe–O yang mendukung hasil identifikasi mineral dari XRD. Kombinasi hasil XRF, XRD, dan FTIR menunjukkan bahwa mortar kuno Mangrove Park Lampulo merupakan mortar berbasis kapur dengan dominasi mineral karbonat dan silikat yang berperan terhadap kestabilan dan ketahanan material selama proses penuaan. Penelitian ini memberikan informasi mengenai teknologi material konstruksi masa lampau yang dapat digunakan sebagai dasar dalam konservasi dan restorasi bangunan bersejarah.

Kata kunci: Mortar kuno, Mangrove Park Lampulo, XRF, XRD, FTIR, Kalsit, Kuarsa, Komposisi mineral.

Mortar is a composite material that has been used since ancient times as a binding material in building construction. Ancient mortar generally consists of a lime-based binder derived from limestone (CaCO₃) and aggregates such as sand, which harden through the carbonation process. This study aims to identify the composition of ancient mortar from the historical Mangrove Park Lampulo (MPL) site based on its elemental composition, crystalline mineral phases, and functional groups. Ancient mortar samples collected from the cemetery boundary wall at Mangrove Park Lampulo were analyzed using X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR). XRF analysis was employed to determine the elemental and oxide compositions of the mortar, XRD was used to identify the crystalline mineral phases, while FTIR was applied to investigate the functional groups and chemical bonds present in the material. The XRF results revealed that the major elements in the ancient mortar were calcium (Ca), silicon (Si), and oxygen (O), together with minor elements originating from the aggregate minerals and the lime binder. XRD characterization showed that the ancient mortar was predominantly composed of calcite (CaCO₃) and quartz (SiO₂), with minor mineral phases including dolomite and iron oxides. The presence of calcite indicates that the primary binding material originated from carbonated lime derived from limestone, whereas quartz originated from the sand aggregate used in the mortar mixture. FTIR analysis identified carbonate (CO₃²⁻), silicate (Si–O), and Fe–O functional groups, supporting the mineralogical identification obtained from XRD. The combined results of XRF, XRD, and FTIR demonstrate that the Mangrove Park Lampulo ancient mortar is a lime-based mortar dominated by carbonate and silicate minerals, which contribute to its long-term stability and durability during the aging process. This study provides valuable insights into ancient construction material technology and serves as a scientific basis for the conservation and restoration of historical buildings. Keywords : Ancient mortar, Mangrove Park Lampulo, XRF, XRD, FTIR, calcite, quartz, mineral composition.