PEMANFAATAN ABU VULKANIK GUNUNG KELUD SEBAGAI POZZOLAN PADA SELF-COMPACTING CONCRETE (SCC) DI BAWAH AIR

LUH AYU CHANDRA K, Prof. Ir. Iman Satyarno, M.E., Ph.D.

2015 | Tesis | S2 Teknik Sipil

Abu vulkanik hasil erupsi Gunung Kelud pada tanggal 14 Februari 2014 menjadi limbah yang belum dimanfaatkan secara optimal oleh masyarakat, sehingga perlu dilakukan upaya untuk mengoptimalkan pemanfaatan limbah abu vulkanik tersebut. Salah satu upaya pemanfaatan abu vulkanik Gunung Kelud adalah sebagai pozzolan pada Self-Compacting Concrete (SCC). Tujuan dari penelitian ini adalah mengetahui kandungan kimia abu vulkanik Gunung Kelud dan pengaruh penggunaannya terhadap karakteristik SCC berupa workability, kuat tekan dan serapan air. Dalam penelitian ini, pembuatan benda uji beton dilakukan pada dua kondisi yaitu kondisi kering dan kondisi di bawah air. Abu vulkanik digunakan sebagai pozzolan dengan persentase 0%, 5%, 10%, 15% dan 20% terhadap berat semen. Masing-masing persentase akan diberikan tambahan superlasticizer jenis Viscocrete-10 dengan dosis 0,8% dari berat binder. Pengujian workability beton segar dilakukan dengan menggunakan Slump-cone dan V-funnel. Pada kondisi keras, pengujian beton yang dilakukan adalah kuat tekan dan serapan air. Hasil penelitian menunjukkan bahwa abu vulkanik Gunung Kelud memiliki 90,49% kandungan (SiO2+Al2O3+Fe2O3). Penambahan persentase abu vulkanik menurunkan workability beton segar SCC, akan tetapi penggunaan abu vulkanik (0-20%) masih memenuhi kriteria yang disyaratkan SCC 028 (2005). Penggunaan abu vulkanik pada SCC di bawah air dapat mengurangi serapan air beton. Pada pengujian kuat tekan SCC kondisi kering dan kondisi di bawah air, kuat tekan optimum dihasilkan dari penggunaan abu vulkanik sebanyak 15% terhadap berat semen. Kata kunci: Self-Compacting Concrete (SCC), abu vulkanik, workability, kuat tekan, serapan air

The volcanic ash blasted by Kelud’s eruption on February 14, 2014 was becoming a waste but has not been used optimally by the public. So it is necessary to attempt to optimize its utilization. One of Kelud’s volcanic ash utilization efforts is by using it as pozzolan in Self-Compacting Concrete (SCC).The purpose of this study was to determine the chemical contents of Kelud’s volcanic ash and its effects on the characteristics of SSC; workability, compressive strength, and water absorption. The manufacture of the concrete specimens in this study was performed in two conditions; dry and under-water condition. The volcanic ash was used as pozzolan with the percentage of 0%, 5%, 10%, 15% and 20% of the cement weight. Each of percentage then be added by superplasticizer Viscocrete-10 at a dose of 0,8% of the weight of the binder. The workability test of the fresh concrete was performed using Slump-cone and V-funnel. In the rigid condition, the test included its compressive strength and water absorption. The results showed that Kelud’s volcanic ash containing (SiO2+Al2O3+Fe2O3) at 90.49%. The addition to the percentage reduced the workability of SCC fresh concrete, but the use of the volcanic ash (0-20%) still meet the required criteria of SCC 028 (2005). The use of the volcanic ash in SCC under water reduced its water absorption. The compressive strength test in both the dry condition and the under-water condition showed that the optimum strength was resulted when the weight of the ash was 15% of the weight of the cement. Key words: Self-Compacting Concrete (SCC), volcanic ash, workability, compressive strength, water absorption

Kata Kunci : Self-Compacting Concrete (SCC), abu vulkanik, workability, kuat tekan, serapan air; Self-Compacting Concrete (SCC), volcanic ash, workability, compressive strength, water absorption