PENGARUH SUBSTITUSI CANGKANG KERANG DARI ENDE NTT TERHADAP KUAT TEKAN DANKUAT LENTUR BETON fc’= 19,3 MPa

Abstract

The use of concrete for basic construction materials today is indeed increasing rapidly along with the development of construction construction.Only a concrete quality of 19.3 MPa (fc '= 25 MPa) was considered in this study. Since cement, aggregates, sand and water are extracted from nature, they must be limited. So in this study using additional material clam shells. One of them is shells, shellfish waste or shells are usually only used as decorations or toys so that there is still a lot of waste wasted. Inside the shell, the clam contains pozzolan chemical compounds, namely lime (CaO), aluminum oxide and silica. It can be expected to improve the quality of concrete.

As a result of compressive strength test by changing the clamshell to 0%, 10%, 20%, 30%, 40% and 50%, the average compressive strength value of 0% (ordinary concrete) was 15.81 MPa. The addition of a 10% clam shell results in an average compressive strength value of 20.58 MPa. For the addition of clam shells by 20% obtained an average compressive strength value of 23.37 MPa. 30% yields an average compressive strength of 40.31 Mpa, to 40% of 29.12 Mpa. As for the addition of 50% clam shells, the average compressive strength value is 24.79 Mpa. Thus it can be concluded that the addition of clam shells 30% compressive strength value is higher than the compressive strength value of concrete with the addition of clam shells 0%, 10%, 20%, 40%, and 50%The flexural strength test value in terms of the maximum average moment on the beam for each variation of the test specimen is maximum moment value 75.02 kN.m for 0% variation, maximum moment value 62.52 kN.m for 10% variation, maximum moment value 68.77 kN.m for 20% variation, maximum moment value for 30% variation 62.52 kN.m, 40% variation at maximum moment value of 62.52 kN.m. Therefore, the percentage of specimens that can withstand the highest load in the flexural strength test is 0% and the maximum moment value is 75.02 kN.m.