Hasanuddin University Graduate School: Open Journal Systems
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Experimental Study on Castellated Beams with Hexagonal Variation Using Monotonic Loading
Get PDFOne method that can be used to economically reduce the weight of steel beam used in the construction is the utilization of castellated beam. The beam is made by using steel material profile split in the middle of the plate web, and the resulting pieces are then welded together in certain method to form a hexagonal shaped hole. This study aims to determine optimal dimension of castellated steel beam that can meet technical requirement such as flexural strength, deflection, and web buckling from the point of web openings and determine load capacity that is able to be borne by castellated steel beam as well as formulizing damaged/failed model that occur on castellated steel beam. In the test of castellated steel beam, 1 normal profile test material of IWF 200.100.5,5.8 and 6 normal profile test materials of IWF 200.100.5,5.8 modified into castellated steel beam with different cutting angle variation  50°,  60°, and spaced web openings 70° fixed at (e) 90 mm and the variation of different web openings distance of 60 mm, 90 mm, and 120 cm with a fixed angle of the cutting body  60°. Test of castellated steel beams was carried out using Static Loading Frame - two-point load in monotonic loading. From the test results it is known that the castellated steel beams with  60°, e = 90 mm is able to withstand the maximum load compared to test material variation of another angle and distance, while the maximum load deflection value is greater than the variations in the value of the angle cut and bend the smaller web. Bending stress and bending moment are higher than the other test materials. In this test, the test specimens still exhibit elastic behavior and has not reached the yielding stress. This is because when the load increases, the beam has been damaged. All test specimens were damaged by buckling and lateral torsion buckling on flange and web profile
Behavior of Castellated Composite Beam-Columns Subjected to Monotonic and Cyclic Loadings
Get PDFThe combination of Castellated beam system with composite beam system by adding in-filled concrete between the flanges of steel beam is expected to increase the capacity to accommodate the force and can overcome the shortcomings found in the two systems. Research was conducted to study the behavior of castellated beam with concrete filler in between the flanges due to earthquake loads. Steel beam IWF profile used was 200 x 100 x 8 x 5.5 with hexagonal openings. The opening height of 0.6 H, the opening distance 9 cm and the angle openings of 600. The test objects consist of normal beam and in-filled concrete castellated steel beam. The data were collected using LVDT and the strain gauges recorded by the data logger and switching box. In addition, data retrieval was also done by visually sighting like buckling and cracking. Testing with cyclic load is a continuation of previous research that uses the monotonic load. The initial load of the yielding of the cyclic load on normal beam and castellated composite beam of 16.5 KN and 43.5 KN and for composite beam with a monotonic load was 360 KN. The initial moment of the yielding of composite castellated beam with cyclic loading was 73.52 kN-m, increased from normal beam capacity of 27.89 kN-m compared with a monotonic load of 81.00 kN-m. Castellated composite beam is capable of receiving loads of bigger and smaller deflection than normal beam. The damage shape failure of normal beam on cyclic load was due to local buckling on the flanges while for castellated composite beam both under cyclic load and monotonic load were concrete cracks
Study on Buckling Strength at Deck Leg of Fixed Offshore Platform
Get PDFA deck of fixed offshore platform is location where the all activities are performed, i.e. deck must be supported by leg with adequately strength under vertical or horizontal loading. The present study is focused on the buckling strength taking the deck leg of fixed jacket offshore platform into account. The axial compressive load is applied to the deck leg of the structure. Because dimension front view and side view of the deck structure is completely different, so that the analysis is conducted by two stages. To investigate the critical buckling load and critical buckling stress including its deformation, the plane-frame (2D) analysis is considered. The Non-linear Finite Element Method so-called Structural Analysis Program (SAP) is adopted for the investigation of the structural behaviors. The critical buckling load and stress ratio obtained by Finite Element Analysis (FEA) is compared with the simple formula. As a result, it can be concluded that the stress ratio of the combination between axial compression and bending is less than 1,0 which indicates that the structure is safe
Effect of Inoculations of Trichoderma viride and Saccharomyces cerevisiae Mixed Culture on Chemical Composition, Fiber, Digestibility and Theobromine Cocoa Pod Fermentation
Get PDFThe objective of the study was to identify the effect of Trichoderma viride andSaccharomyces cerevisiae inoculant on chemical compositions, digestibility, and theobromineconcentration of fermented cocoa pod. This experiment consisted of four treatments,namely cocoa pods without fermentation as control (R0); fermentation of cocoa pods withinoculant T. viride (R1); fermentation of cocoa pods with inoculant S. cerevisiae (R2); andfermentation of cocoa pods with inoculant T. viride and S. cerevisiae mixed culture (R3).Each treatment had 3 replicates, and then was fermented for 10 days. Variables observedwere the chemical compositions i.e dry matter (DM), organic matter (OM), crude protein(CP), ether extract (EE), crude fiber (CF), nitrogen free extract (NFE), fiber fraction (Neutraldetergent fiber and acid detergent fiber), in vitro digestibility, and theobromine concentration.Data were analysed by one-way analysis of variance and followed by Duncan’s new multiplerange test (DMRT), if there were any significant difference. Results showed the inoculumaffected (P<0.05) the chemical composition, fiber fraction and in vitro digestibility. However,theobromine was not detected on cocoa pod without fermentation and fermentation.Compared to group R0, inoculation with T. viride and S. cerevisiae mixed culture (P<0.05)resulted in higher DM concentration (92.78% vs 89.72% respectively), higher CP (7.43% vs5.63% respectively), higher NDF (79.41% vs 61.18% respectively), higher ADF (73.04%vs 47.94% respectively), but was not significantly different on DM and OM digestibility(21.22% vs 22.24%, and 22.67% vs 24.31% respectively) than cocoa pod without fermentation.It is concluded that inoculant T. viride and S. cerevisiae mixed culture increased CPconcentration, but had no effect on in vitro digestibility
Risk Model Contract Based Performance Road Work in Indonesia
Get PDFPerformance-based contract is a solution for road maintenance in the form of integrated contracts of process design, execution and maintenance of construction lump sum payment system. The purpose of this study is to formulate a model of the relationship of risk to the performance of performance based contract. The research methodology done using the method in which the survey questionnaire as data collection instruments were distributed to the parties involved in projects performance-based contract in Indonesia. Then the data is processed by factor analysis, regression analysis and path analysis to obtain structural equation relationship PBC risk and project performance. The results showed that there are 31 of the most important risks that affect project performance cost, time and quality. Of the 31 identified risks, there are 12 risk factors that directly affect and significant impact on all aspects of project performance-based contract. From the formulation of the resulting model obtained a function of the parameters 3 empirical models path diagram that explains the correlation risks to project performance-based contract, the empirical model 1 risk relationship to the performance fee, the empirical model 2 risk relationship to performance time and empirical models of 3 risk relationship to performance quality
Motions Analysis of a Phinisi Ship Hull with New Strip Method
Get PDFPhinisi is the name of a renowned traditional wooden ship from South Sulawesi, Indonesia. The ship has been proven to be tough and reliable in sailing even to this very day. However, the ship is built only with a very traditional method and simple tools. There is no hydrodynamic analysis performed prior to the building of the ship. Therefore, in order to analyze the performance of the ship motion of a Phinisi ship hull, New Strip Method (NSM) is employed in the present study. With NSM, the ship hull is divided into several strips and the hydrodynamics forces are computed on each strip. Moreover, because the ship is assumed to be slender, the total forces are obtained by integrating the force on each strip. From the computation results, it can be shown that the resonant frequency of the analyzed Phinisi hull is shifted to lower frequency as the ship speed increases
Experimental Study of Vetiver Phytoremediation on Compost Clay with Chromium (Cr) and Cadmium (Cd) Contaminant
Get PDFA study was conducted to analyze the absoption and reduction capacity of cadmium and chromium metal in clay soil and clay soil plus compost artificiallly polluted with several Cd and Cr concentrations after phytoremediation process using several number of vetiver (Vetiverazizanioides) plants/ pot growing. The study testing 18 treatment combinations which were consisted of three Cr concentration (400, 6000, and 800 ppm), three number of vetiver plants (3, 6, and 9 plants/ pot), two growing media (clay and 80% clay + 20% compost). The more number of plants and the higher concentration of metals Cd, the higher capacity reduction Cd metals in the soil and the higher Cd metal absorption by vetiver plants. The higher number of vetiver plants grown the higher Cd and Cr in clay and clay plus compost media were absorbed and reduced. The levels of Cd and Cr in clay and clay plus compost media absorbed were followed by the more reduction of Cd and C
Experimental Study on Precast Buton Asphalt Pavement Panel Strengthened with Geogrid
Get PDFPrecast buton asphalt panels having the same characteristics with the characteristics of the massive asphalt can be used as an alternative method for the use of the asphalt pavement as an effort to simplify and reduce of implementation errors, so that it can increase the attractiveness of the use of buton asphalt. The experimental programs were conducted at the Civil Engineering Laboratory, Hasanuddin University. Testing of materials namely asphalt, coarse and fine aggregate were conducted to obtain the characteristics of each material. The next phase of the tests was carried out on various mixtures of the mix asphalt concrete (AC-WC) to obtain the optimum bitumen content to be used for determining the panels. Testing on panels with the size of 40 x 30 cm with a varying thickness was conducted at the final stage. The experimental results show that the use of geogrid is able to raise the buton asphalt panel's ability to withstand a static load and increase the flexibility of the panel. The most effective panel was found for a panel with a thickness of 5 cm. It can not only increase the maximum static load bearing capability but also increase in the maximum deflection before collaps
Lighting Analysis at Access Zone of Tunnel Entrance of Hong Kong-Zuhai-Macao Bridge (HZMB)
Get PDFThe study aimed to evaluate several shading schemes at access zone of the tunnel entrance of HZMB in order to find the best scenario to increase the user lighting comfort. The study analysed the luminance at the tunnel entrance (L20) and energy saving in the thereshold zone. For these analyses, four shading schemes have been simulated. The schemes were the Original Scheme (Zebra, 50% solid & 50% transparent), Option 1 (Gradation Glass), Option 2 (Perforated Material), and Option 3 (No Shading). The results shows that the Original scheme has the lowest L20 luminance and consequently the highest lighting energy saving. While the Option 3 (No Shading) has the highest L20 luminance and consequently the lowest lighting energy saving
Analyzing Determinant Components on East Java Rice Surplus Contribution Using Dynamical System Approach
Get PDFThe Ministry of Agriculture has proclaimed rice as a main food commodity, beside corn, soybeans, meat and sugar. In order to achieve the target of the Ministry of Agriculture, East Java provincial government has stipulated a policy, focusing on rice surplus of 5 million tons in 2014. This attempt is to reach the surplus number through a wide selection of technological innovations (determinant component) that increases the productivity of rice (New Superior Variety/VUB, Site Specific Nutrient Management/SSNM, Integreted Crop Management/ PTT, Jarwo/double row planting system, balanced fertilization, SOP harvest / postharvest), as well as an increase in Planting Index/IP by improving irrigation and food diversification program. By using a dynamical system approach (modeling), it can be measured the contribution of each determinant components in achieving surplus / rice self-sufficiency through simulation. The results of the simulation, it was known that the East Java’s rice surplus will continue to decline from 1,806,282 tons (2014) with 170% self-sufficiency index, fell to 1.706.771 tons (2017) and would be 1.367.901 tons (2025). This condition is due to the increasing number of population, agricultural area continues to shrink and productivity is relatively fixed. Index sufficiency / surplus will increase if there is an interference of educational policy to implement a massive exceed of VUB, SSNM, PTT, Jarwo, balanced fertilization, SOP harvest / post-harvest, IP increasing and the succession of diversification in East Java. A surplus of 4.7 million tons of rice in 2014 within East Java can be achieved by implementing massive educational policy movement of PTT and VUB (100% of the area), the application of SOP harvest / post-harvest to reach at least 50% of the area of paddy and controlling OPT strictly. The highest self-sufficiency index (281%) and a surplus of 5.22 million tons will be achieved in case of an interference in implementing policy of PTT jarwo (100% of the area) and an IP increasing amounted to 1.0 (additional areas that can be irrigated, 33.000 ha). Sustainable rice surplus would be achieved in case of an attempt to make food diversification program completely successful, strengthen family planning programs and strictly guard the Regulation No. 5/2012 on the minimum acreage of paddy fields that must be maintained