THE EFFECT OF LCP ADDITION TO THE COMPRESSIVE STRENGTH OF NORMAL CONCRETE

. SNI 03-2847-2002, Concrete is a mixture of portland cement or other hydraulic cements, fine aggregate, coarse aggregate and water. The additives that form solid mass are optional. The aims of this study are to find out the effect of waste nugmet shell (LCP) toward the concrete characteristics, and to determine the compressive strength value of concrete characteristics. Variation of waste nugmet shell (LCP) toward the weight of cement is 0%, 0.25%, 0.50%, and 0.75%. This research is a sample-based laboratory research and analysis of aggregate characteristics and concrete compression test. The research result shows that the waste nugmet shell (LCP) into the concrete mixture affects the compressive strength value of concrete characteristics (fck’). It is proved by the compressive strength value of concrete which increased with the of waste nugmet shell (LCP) 0,25% and LCP 0,50% then decreased after the LCP 0,75%. The increase of fck’ value of the concrete characteristics after LCP 0.25% and LCP 0,50% is equal to 80.03 Kg/cm 2 and 86.13 Kg / cm 2 . It means that there is an increase about 16.34% and 22,26%. The increase of concrete compressive strength value is quite significant if it is compared to non-LCP (normal concrete) with fck’ value about 66,95 Kg/cm 2 . Meanwhile, the decrease of fck’ value occurs in the proportion of LCP 0.75%, with the value of fck’ obtained t 64.56 Kg/cm 2 at the age of 28 days.


INTRODUCTION
Concrete is composite material consisted of aggregate and wrapped up by cement matrix. The matrix fills the space between particles so unity is formed. Based on the compressive strength, concrete is divided into three; normal concrete, high performance and very high performance. Concrete has some advantages such as: the pressure strength is relatively high, easily shaped as desired, cheap maintenance, and combinable with other materials [1].
SNI 03-2847-2002, describes concrete as a construction material consisted of mixture of Portland cement or other hydraulic cements, fine aggregate, coarse aggregate, and water. The additives that form solid mass are optional [2].
The additives are materials except the main components of concrete (water, cement, and aggregate) which are added to the concrete mixture. This aims to change one or more concrete properties while still in fresh condition or after hardening, for example the accelerating hardening, increasing ductility (reducing brittle properties), reducing hardening cracks, etc. [3].
The addition of other materials such as natural fibers in the normal concrete certainly has its own way of analysis. The addition of fibers in certain proportions is likely to affect the behavior of the whole concrete structure. The effect of this change needs to be examined to provide precise information on fibrous fiber behavior and capacity especially the use of fiber from nutmeg waste.
Fakfak Regency is one of the regencies in West Papua Province consisting of 123 villages with abundant agricultural products such as nutmeg (produced 3,187,500 tons in a year), with a land area of 936,749.39 hectares. Until now, it has become a commodity of superior nutmeg and as a spice plant needed both locally and internationally [4].
The production of nutmeg is abundant and this will be proportional to the nutmeg shell that is produced as well. The nutmeg shells are just thrown away and burned, then become waste, so steps need to be taken to p-ISSN : 1412-114X e-ISSN : 2580-5649 http://ojs.pnb.ac.id/index.php/LOGIC overcome them. One way to handle such waste is to use it as a concrete material. According to Danusaputro [5], if this waste is disposed of continuously in the absence of maximum processing, this can cause a disturbance of balance, thus causing the environment to be unable to function properly in terms of health, well-being and biosafety.
The advantages of natural fiber waste nutmeg waste than other fibers is that this fiber is lighter, so it can affect the volume of weight of concrete and its availability is quite abundant. The purpose of this research is to determine the influence and value of compressive strength of concrete characteristics. Variation of waste nutmeg waste (LCP) was 0%; 0.25%; 0.50%; and 0.75% of the weight of cement.

RESEARCH METHOD 2.1 Research Design
The primary data collection for this research is the result of testing of aggregate characteristics of coarse and fine aggregate. This test consists of testing the level of sludge, moisture content, volume weight, absorption, density, modulus of fineness and roughness modulus. After testing the characteristic of coarse and fine aggregate, it is continued with normal and concrete mix design design with LCP percentage equal to 0,25%, 0,50% and 0,75% to cement weight by using cylinder size 15x30 cm. Concrete testing was performed after concrete immersion at age 3, 7 and 28 days. The study sample design is presented as in Table 1.

Characteristic Testing
Aggregate characteristic testing uses study literatures as shown in Table 2.

Testing of Aggregate Characteristic
The results of the characteristic test of coarse aggregate (gravel) are as in Table 3 whereas the results of fine aggregate testing (sand) as in Table 4. Based on the results of the test table 3, it is explained that on the test of mud content on coarse aggregate, obtained value of 1.04% beyond the interval limit is maximum 1%. This is due to the rough aggregate used in this study including local stone with high lime content.  Table 4, fine aggregate characteristic testing meets the requirements, although this test uses marine sand due to material limitations. The test result qualifies zone 2 by entering a rather rough category with a fineness modulus of 2,656. Graph of gradation test results of fine aggregate grains shown as in Figure 2. To know the strength of concrete quality that will be produced by using coarse aggregate (gravel) and fine aggregate (sand), used concrete quality f'c 175 Mpa. From the calculation of aggregate combination, it is obtained 30% sand and 70% crushed stone on mixed concrete with cement water factor (W / C) = 0,75 like table 5 while for addition of nutmeg waste (LCP) with variation 0,25% , 0.50% and 0.75% as shown in Table 6, 7, and 8.    After the calculation of the mixture of normal and concrete mixture with the addition of LCP is obtained, the next is mixing with the weight of fresh (wet) concrete volume as in Table 9. Based on table 9, the weight of freshly produced concrete volume decreases with the percentage value of the nutmeg waste addition (LCP) compared to the normal concrete mix design, where the weight of the concrete volume obtained from the LCP addition is lighter. The results of fresh concrete testing are as in Table 10. Based on table 10, the normal weight of concrete before adding nutmeg waste nutmeg was 2372,746 kg / m3, when compared to the weight of concrete after the addition of LCP 0,25% which was 2305,031 kg / m3, decreased 2.85 %. Similarly, the weight of concrete on the addition of LCP 0.50%, and 0.75% decreased by 4.04% and 5.59%, respectively. This is because the higher the percentage of LCP put into concrete mix will reduce the volume of concrete that should be filled by cement paste so that it affects the weight of fresh concrete. The result of compressive strength test of concrete characteristic (fck ') at age 28 day by using correction factor in normal sample with 0% LCP addition, the value of compressive strength is 66,95 kg / cm2, sample with addition of LCP 0,25 % of 80,03 kg / cm2, sample with LCP 0,50% equal to 86,13 kg / cm2 and CLP sample 0,75% obtained 72,84 kg / cm2 as in Table 11, 12, 13, and 14.  The recapitulation of the result of compressive strength testing of concrete characteristic with or without LCP is as shown in Table 15. When compared to normal concrete with concrete after addition of nutmeg shell waste (LCP), concrete strength value increase in the proportion of LCP added 0,25% and 0,50% that is equal to 80,03 kg / cm2 and 86,13 kg / cm2, an increase of 16.34% and 22.26%. However the value of concrete compressive strength decreased at the proportion of LCP addition of 0.75% at 64.56 kg / cm2, with a decrease of 3.70% of normal concrete. The decrease of compressive strength value is influenced by more percentage of nutmeg waste which is inserted into the concrete slab so as to reduce the volume of concrete that should be filled by cement paste so that it affects the compressive strength value of concrete and the use of the sand material also causes low concrete quality value.

CONCLUSION AND SUGGESTION 4.1 Conclusion
Based on the results of research and data analysis that has been implemented, it can be concluded some points as follows: 1. The addition of nutmeg waste (LCP) to the concrete mix affects the strength value of the concrete characteristic strength (fck '), where the value of concrete compressive strength increases in the addition of LCP 0.25% and LCP 0.50%, and decreases after the addition of LCP 0, 75%.