Degradasi Kekuatan Beton Akibat Intrusi Mikroorganisme
DOI:
https://doi.org/10.5614/jts.2006.13.3.4Keywords:
Degradasi beton, Intrusi Mikroorganisme, Jamur, ragi, Koloni mikroorganisme.Abstract
Abstrak. Makalah ini merupakan hasil studi eksperimental perilaku degradasi kekuatan beton di bawah kondisi intrusif mikroorganisme. Media intrusi yang digunakan berupa air kelapa dengan proses fermentasi alamiah. Produksi dominan mikroorganisme dengan media ini adalah dari golongan jamur dan ragi. Mikroorganisme dapat berkembang di dalam beton karena tersedianya nutrisi berupa kapur bebas dari hasil sampingan proses reaksi. Mikroorganisme dalam aktivitasnya memproduksi asam sulfur (H2SO4) yang jika bereaksi dengan kalsium hidoksida (CaOH), dapat berakibat degradasi/penurunan kekuatan beton. Hasil penelitian menunjukkan beton mutu rendah lebih sensitif terhadap degradasi kekuatan akibat intrusi mikroorganisme. Degradasi kekuatan beton dalam interval waktu dua tahun dapat mencapai kehilangan kekuatan sampai 60% untuk fc' = 25 MPa, 50% untuk fc' = 40 MPa, dan sampai 33% untuk fc' = 60 MPa.Abstract. This paper presents the experimental study on concrete strength degradation under intrusive of microorganism. The intrusion media of coconut water with natural fermentation process produces microorganism with dominant elements are aspergillus niger and sacchromycode ludwigi. The microorganism may be well spread in concrete due to nutrition such as free lime from reaction process. The microorganism in its present in concrete produces sulfuric acid (H2SO4) and its reaction with calsium hydroxide (CaOH) causes strength reduction in concrete. Experimental result shows that for concrete of minimum strength, its strength degradation is more sensitive due to intrusion microorganism. The degradation in strength concrete may be of range 60% for concrete strength fc' = 25 MPa, 50% for fc' = 40 MPa, and 33% for fc' = 60 MPa.
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