ANALISIS KUALITAS MORTAR YANG DITAMBAHKAN ABU TERBANG (FLY ASH) SEBAGAI PENGGANTI SEBAGIAN SEMEN

Mortar is one of the building materials used in non-structural work by using cement, sand and water. Duringthis time mortar is still using cement as the main bonding material. Therefore, an alternative ikat material is needed toreduce the dependence of cement use. Alternative binding materials used in this study is the residual coal combustion offly ash. Fly ash is a material that has a small grain size, round, not porous and is pozzolanik. Cement productionproduces significant amounts of carbon dioxide (CO2) resulting in an agreenhouse gas effect. 65% of global warming(Global Warming) is caused by CO2 emissions, about 6% coming from the cement industry (the production of one tonof portlan cement emits about one ton of CO2 into the atmosphere.The addition of fly ash to the mortar mixture ispozzolan, good mineral additive for mortar Pozzolan is a material containing silica or silica and aluminum which reactschemically with calcium hydroxide at ordinary temperature to form cementitious compounds. This research aims toknow the effect of fly ash utilization as partial replacement of cement with setting time , consistency , and compressivestrength of mortar The cube-shaped specimen measures 50 mm x 50 mm x 50 mm, the composition of the mixture withfly ash as a substitute for PCC cement by 0%, 10%, 20%, and 30% Comparison of cement and sand used is 1: 3. Testingof mortar compressive strength at age 3, 7, 14, 28, and 90 days .. The results showed that the higher the percentage of flyash content used, the higher the mortar consistency value. For setting time, the higher the addition of fly ash, the initialsetting time and the final setting time are slower. Strong strength tends to increase with the use of fly ash, especially atthe age of 28 days and 90 days