PEMANFAATAN ABU VULKANIK GUNUNG KELUD SEBAGAI PENGGANTI SEBAGIAN AGREGAT HALUS PADA BETON NORMAL SEBAGAI PENDUKUNG BAHAN AJAR MATA KULIAH TEKNOLOGI BETON (PADA MAHASISWA PTB, JPTK, UNS)
Authors: Anshory Abdul Rohman , Sumarni Sri , Roemintoyo Roemintoyo 
Published: April 2018

<p><span style="font-size: 11pt; color: #000000; font-style: normal; font-variant: normal;"><em>The purpose of this study was to determine (1) Effect of volcanic ash in partial replacement of</em> <span style="font-size: 11pt; color: #000000; font-style: normal; font-variant: normal;"><em>the total fine aggregate of compressive strength and the density of the concrete, (2) resistance to the</em><br /><span style="font-size: 11pt; color: #000000; font-style: normal; font-variant: normal;"><em>optimal compression of the concrete (3) optimum density concrete. (4) The teaching material obtained in</em><br /><span style="font-size: 11pt; color: #000000; font-style: normal; font-variant: normal;"><em>the course of concrete technology on the effect of volcanic ash on the compressive strength of concrete</em><br /><span style="font-size: 11pt; color: #000000; font-style: normal; font-variant: normal;"><em>and normal density. Experimental studies using methods and analytical techniques using a quantitative</em><br /><span style="font-size: 11pt; color: #000000; font-style: normal; font-variant: normal;"><em>analysis of regression. Variables in the study were (1) the dependent variable: the strength of concrete in</em><br /><span style="font-size: 11pt; color: #000000; font-style: normal; font-variant: normal;"><em>compression and the density of concrete, (2) independent variables: the variation of 0%, 10%, 15%, 20%</em><br /><span style="font-size: 11pt; color: #000000; font-style: normal; font-variant: normal;"><em>and 25% Volcanic ash from the total weight of the sand. The sampel is in the form of a cylinder with a</em><br /><span style="font-size: 11pt; color: #000000; font-style: normal; font-variant: normal;"><em>diameter of 150 mm and a height of 300 mm. Based on the results of the study concluded that (1) changes</em><br /><span style="font-size: 11pt; color: #000000; font-style: normal; font-variant: normal;"><em>in volcanic ash as a partial replacement of the fine aggregate strong overall influence on the compressive</em><br /><span style="font-size: 11pt; color: #000000; font-style: normal; font-variant: normal;"><em>strength and density of concrete, (2) the optimal value of compressive strength and the weight of each</em><br /><span style="font-size: 11pt; color: #000000; font-style: normal; font-variant: normal;"><em>type of concrete which is the variation of volcanic ash 8,36% amounted to 23,231 MPa, 11,889% to</em><br /><span style="font-size: 11pt; color: #000000; font-style: normal; font-variant: normal;"><em>22,919 MPa, (3) the value of the optimal concrete mixture as a whole, to namely the variation of volcanic</em><br /><span style="font-size: 11pt; color: #000000; font-style: normal; font-variant: normal;"><em>ash 11,889% (4) in the form of teaching material to supplement teaching materials using Kelud volcanic</em><br /><span style="font-size: 11pt; color: #000000; font-style: normal; font-variant: normal;"><em>ash as a partial replacement of fine aggregate on in terms of compressive strength concrete and density.</em></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></p><p><span style="font-size: 11pt; color: #000000; font-style: normal; font-variant: normal;"><span style="font-size: 12pt; color: #000000; font-style: normal; font-variant: normal;"><strong>Key words: </strong><span style="font-size: 12pt; color: #000000; font-style: normal; font-variant: normal;"><em>normal concrete, volcanic ash, compressive strength, density</em></span></span><br style="font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px;" /></span></p>