Bonding Capacity of Deform Bar in Sea Water Concrete

The seawater contains about 35,000 ppm is dissolved salt which can increase the risk of corrosion in steel reinforcement embedded in concrete.  This study aims to determine the value of bond strength of seawater concrete with steel reinforcement. This research uses experimental test method in laboratory which includes compressive strength test, concrete split tensile strength test, tensile strength of deform bar, pull out test and visual observation of carbonation test.  The specimens in this study was made in 3 different types of curing, i.e. wet curing, dry curing and wet-dry curing. The result of the research obtain the compressive strength for 28 days for dry curing is 17.15 MPa,  while for wet curing and dry-wet curing about 16.895 MPa and 19.367 MPa, respectively. The split tensile strength of concrete after 28 days for dry curing, wet curing, and dry-wet curing are 7.55 MPa, 8.85 MPa and 7.55 MP, respectively.  The bond strength specimen for 28 days in dry curing was 5.46 MPa, whereas specimen in the wet curing and dry wet curing showed bond strength about 5.94 MPa and 4.90 MPa, respectively. Based on the result, compressive strength in wet-dry curing showed higher value than others curing types, while specimen in wet curing presented the value of split tensile strength and bond strength higher than dry curing and wet-dry curing

Behaviour of Optimized Honey Comb Beam Under Monotonic Loading

Honey comb beam is a steel beam which has opening on its web. The advantage of this beam is to increase the bending capacity of the beam due to increasing of inertia moment and plastic moment of steel beam section. There are three important variables which determining the capacity of the honey comb beam, i.e. opening space, opening angle, and opening ratio of the honey comb beam. This paper presents the behavior of honey comb beam which has firstly been optimized and has been done by using fast multi swarm optimization (FMSO). In the previous research, there are two cases of optimization considered. First case is optimization of opening space and opening angle with certain opening ratio, while the second case is optimization of opening space, opening angle, and opening ratio. Based on FMSO, the result showed that the second case of optimization has a better result than first case of optimization. Therefore, in order to validate the result of FMSO, the finite element analysis was conducted to obtain the behavior of optimized section of honey comb beam using monotonic loading

Flexural Behavior of Styrofoam-Filled Concrete

Various kinds of innovations have been made to obtain lightweight concrete, for example using Styrofoam as partial replacement of aggregates. The objective of this study was to analyze the flexural behavior of Styrofoam-filled Concrete (SFC) by adding Styrofoam 30 % to replace the concrete volume. The testing was carried out on three variations specimens with a total of 6 specimens, which each variation consist of 2 specimens. The characteristic of Normal Concrete (NC) and SFC was first evaluated. Then, the behavior of SFC beam was compared with the behavior of NC beam and SFC with CFRP strengthening (SFC-CFRP). The specimens were statically loaded using two-point load system with constant speed ramp actuator at 0.1 mm/second until the beam failure. The results indicate that the strength of normal concrete (NC) and SFC has decreased with addition of 30% Styrofoam. However, when the SFC beam was combined with deformed bar, the ultimate bending strength of SFC specimens increase 12.6% compared to the NC specimens. Similarly, the ultimate strength of SFC-CFRP specimens improved by 39.74% compared to the SFC specimens

Sizing Optimization of Retaining Wall by Firefly Algorithm

Retaining wall is used to retain the lateral pressure of soil and surface loading. It has been widely used for application in civil engineering structure such as fill application, roadway cut, etc. This paper considered a firefly algorithm to find out the optimum size and shape of retaining wall with 7m of height and subjected to various loading (5kN/m2, 10kN/m2, 20kN/m2, 40kN/m2). There are four design variables considered for optimization. The objective is to minimize the weight of the retaining wall without violating the requirement of retaining wall. This paper considered stability check of the retaining wall such as overturning stability, sliding stability, and bearing capacity of the soil under the retaining wall. The result shows that the shape of retaining wall with load of 5kN/m2 and 10kN/m2 were similar, the body of the retaining wall were rectangular while the shape of retaining wall with load of 20kN/m2 and 40kN/m2 were trapezoidal. Sliding stability became design control for all loading cases compared by other stability problem (overturning and bearing capacity of soil under the retaining wall). Therefore, it can be concluded that firefly algorithm has successfully been applied to optimize the retaining wall

Pendampingan Dan Pelatihan Diversifikasi Pengolahan Ikan Bagi Ibu-Ibu Nelayan Di Pulau Sembilan Kabupaten Sinjai

Community service is intended to educate or transfer knowledge from information sources to recipients of information. This program has provided changes both socially and economically with the main target being welfare. The Sembilan Island region is one of the areas located in Sinjai Regency which has considerable land and sea potential. The marine and fisheries sector in this region in the short term is known as a sector that is able to have an impact on production activities from other sectors (Output Multiplier / OM) and increase in people's income (Income Multiplier / IM). The community service program that has been carried out involves 30 fishermen mothers in Pulau Sembilan and divided into 5 small groups accompanied by tutorials. Fish is processed into various products including fish balls, fish nuggets and shredded fish. The assistance and training that has been done have increased the community's confidence in increasing their income (Income Multiplier / IM) so that they can sustain the community's economy in Sembilan Island, Sinjai Regency. Key Words: Training, Diversification, Processed Products, Fisherme

Experimental Study on Cement and Fine Aggregate Replacement with Coal Bottom Ash in Seawater-Mixed Concrete

An experimental study was carried out to study the properties of concrete made with seawater as total mixing water, ground coal bottom ash as binary cement and coal bottom ash as sand replacement. The first stage mixes were prepared with three percentages (0, 10, 20 and 30) of ground coal bottom ash as partial replacement of binder. The second stage mixes involved 10 percent of ground coal bottom ash with 25%, 50%, 75% and 100% of coal bottom ash replacing natural sand. Properties investigated were materials properties, binder chemical composition, concrete hardened density, compressive strength, and SEM.  Test on hardened density was conducted on 7 and 28 days. Ground coal bottom ash was identified as Class F, while coal bottom ash has low specific density and high-water absorption compared to natural sand. Concrete density and compressive strength decreased on use of coal bottom ash as fine aggregate. Compressive strength was seen to decrease as CBA percentage rose, with the maximum value being 44.4 MPa for combination of 10 percent ground coal bottom ash and 25 percent coal bottom ash. Series with 10% CBA (ground coal bottom ash) reduces by roughly 51% while maintaining a sufficient structural strength value. The findings of this investigation showed that it is possible to produce seawater-concrete, which incorporates coal ash in concrete

Experimental Study on Cement and Fine Aggregate Replacement with Coal Bottom Ash in Seawater-Mixed Concrete

An experimental study was carried out to study the properties of concrete made with seawater as total mixing water, ground coal bottom ash as binary cement and coal bottom ash as sand replacement. The first stage mixes were prepared with three percentages (0, 10, 20 and 30) of ground coal bottom ash as partial replacement of binder. The second stage mixes involved 10 percent of ground coal bottom ash with 25%, 50%, 75% and 100% of coal bottom ash replacing natural sand. Properties investigated were materials properties, binder chemical composition, concrete hardened density, compressive strength, and SEM.  Test on hardened density was conducted on 7 and 28 days. Ground coal bottom ash was identified as Class F, while coal bottom ash has low specific density and high-water absorption compared to natural sand. Concrete density and compressive strength decreased on use of coal bottom ash as fine aggregate. Compressive strength was seen to decrease as CBA percentage rose, with the maximum value being 44.4 MPa for combination of 10 percent ground coal bottom ash and 25 percent coal bottom ash. Series with 10% CBA (ground coal bottom ash) reduces by roughly 51% while maintaining a sufficient structural strength value. The findings of this investigation showed that it is possible to produce seawater-concrete, which incorporates coal ash in concrete

Influence of the curing method on compressive strength and porosity of concrete mixed with sea water, marine sand and fly ash

There many archipelagic state such as Japan, Indonesia and other countries. Indonesia consists of thousands of islands where many peoples live in the low land area, the distant and isolated islands that lack of clean water or fresh water and mountain sand or river sand.Transporting the fresh water or clean water and mountain\ud aggregates or river aggregates for concrete production to the low land area, the distant and isolated islands will make the price of concrete work becomes more expensive. In order to overcome the problem of shortage of clean water and fine aggregate in the low land area, the distant island, and saving the fresh water over the world, this research seeks to use sea water and sea sand to produce concrete. In order to overcoming the continuous dumping of waste material, this research also uses semen containing wasted material such as fly ash. This research is a part of ongoing investigation that\ud focuses to study the mix design), mechanical properties (compressive strength-modulus elasticity), porosity, and curing method in order to achieve an optimum correlation between sea water, marine sand, cement, river or mountain coarse\ud aggregate in production of high performance concrete. Furthermore, it is important to conduct research on utilization of sea water, whose percentage is 97% of the total water on the earth, as an effort for improving the technology of saving fresh water

COMPARATIVE STUDY: THE DIFFERENCES STUDENTS’ LEARNING BASED ON GENDER

This research is motivated by variuous ways in students absorb, organize and process information received, such as there are students easier to remember the material given visually than auditory or vice, there are students who difficult to write, but good telling stories, there are students who easily disturbed by noise, there are students can't sit still for a long time and there are students prefer practical activities. This study is a comparative to determine differences in learning styles between male and female students at SMP Yapis Merauke. The research sample amounted to 80 students. Data was collected from a learning style questionnaire and analyzed descriptively and inferentially. Descriptive analysis shows dominant male students had auditory and dominant female students had a visual learning style. Inferential analysis with the Anova test showed a significant value of p=0,00 (p<0,05), which means a difference between the learning styles of males and female