The Use of PT Petro Kimia’s by-Product Gypsum as Fill Materials

Raditya Widiatama, Indrasurya Budisatria Mochtar, Noor Endah Mochtar

Abstract


Gypsum is a by-product of the Phosphoric Acid factory PT Gresik Petrochemicals; it is produced around 1,200,000 tons/year. In order to reduce the amount, an effort needed to use gypsum as fill materials. For this purpose, the problem needs to be considered is that gypsum should not contain substances that harmful to the environment and meet the fill materials requirements. In order to answer all these questions, chemical tests were carried out to determine its heavy metal content. Gypsum plasticity and its particle size distribution were determined by conducting Atterberg limit and sieve analysis tests. Compaction test and CBR test were also carried out to determine the density and its strength. Those results were then analyzed using "The Fifteen Point Method" to obtain a relationship curve between dry density (d) and soaked-CBR. This curve was important to determine the soaked-CBR that can be achieved by gypsum materials in the field with different compaction energy 90%, 95%, and 100% of maximum compaction energy. Chemical test result shows that all heavy metals content in gypsum material are far below the regulatory limit; therefore, it is safe for the environment. Besides, Gypsum is non-plastic (NP) material and it is classified as A-4 (AASHTO) or SM (USCS); it means that Gypsum is very good for fill materials and safe to the environment. In addition, the result from the Fifteen Point Method shows that the minimum soaked CBR value is 13% achieved by using 90% of maximum compaction energy with 30-40 % of water content. It means that the gypsum material can be used as selected fill material because it fulfils its requirement where IP10%.

Keywords


By-Product; CBR; Fill Materials; Gypsum; Soil Compaction

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References


Presiden Republik Indonesia. “Pengelolaan Limbah Berbahaya dan Beracun”. Peraturan Pemerintah; Kementerian Sekretariat Negara RI, No 101. 2014.

Badan Standardisasi Nasional (BSN). “Metode Pengujian Berat Jenis Tanah”. Departemen Pekerjaan Umum, SNI 03-1964-1990. 1990.

Badan Standardisasi Nasional (BSN). “Metode Pengujian Batas Plastis Tanah”. Departemen Pekerjaan Umum, SNI 03-1966-1990. 1990.

Badan Standardisasi Nasional (BSN). “Metode Pengujian Batas Cair Tanah”. Departemen Pekerjaan Umum, SNI 03-1967-1990. 1990

Badan Standardisasi Nasional (BSN). “Metode Pengujian Batas Susut Tanah”. Departemen Pekerjaan Umum, SNI 03-3422-1994. 1994.

Badan Standardisasi Nasional (BSN). “Metode Pengujian Analisis Ukuran Butir Tanah dengan Alat Hidrometer”. Departemen Pekerjaan Umum, SNI 03-3423-1994. 1994.

Badan Standardisasi Nasional (BSN). “Metode Pengujian Tentang Analisis Saringan Agregat Halus dan Kasar”. Departemen Pekerjaan Umum, SNI 03-1968-1990. 1990.

AASHTO. “AASHTO Guide for Design of Pavement Structures American Association of State Highway and Transportation Officials, T-27-74. 1993.

ASTM. “Unified Soil Classification System”. American Society for Testing and Materials, C-130-46. 1969.

Badan Standardisasi Nasional (BSN). “Metode Pengujian Berat Isi Tanah Berbutir Halus dengan Cetakan Benda Uji”. Departemen Pekerjaan Umum, SNI 03-3637-1994. 1994.

Badan Standardisasi Nasional (BSN). “Metode Pengujian Kadar Air Agregat”. Departemen Pekerjaan Umum, SNI 03-1965-1990. 1990.

Badan Standardisasi Nasional (BSN). “Metode Pengujian Kepadatan Ringan untuk Tanah”. Departemen Pekerjaan Umum, SNI 03-1742-1989. 1989.

Badan Standardisasi Nasional (BSN). “Metode Pengujian Kepadatan Berat untuk Tanah”. Departemen Pekerjaan Umum, SNI 03-1743-1989. 1989.

Badan Standardisasi Nasional (BSN). “Metode Pengujian CBR Laboratorium”. Departemen Pekerjaan Umum, SNI 03-1744-1989. 1989.

EPA. “Toxicity Characteristic Leaching Procedure”. United States Environmental Protection Agency, Method 1311. 1992

The Asphalt Institute. “Soil Manual for Design of Asphalt Pavement Structures”. 3rd Printing; Manual Series, No 10 (MS-10). 1969.

Kementerian Pekerjaan Umum dan Perumahan Rakyat (PUPR), ”Spesifikasi Pekerjaan Tanah”, Modul 4, Jakarta, 2016.




DOI: http://dx.doi.org/10.12962/j23546026.y2020i6.11087

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