Aceh International Journal of Science and Technology
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Priority Handling of Teurebeh Irrigation Assets, Aceh Besar District, Aceh Province
Full text linkTeurebeh Irrigation scheme is one of the promising irrigation areas in Aceh Besar District, Aceh Province. It is also one of the buffers in the agricultural sector, covering 750 hectares of agricultural area. However, the construction has shrunk over time, and the evaluation at the end of 2020 classified it as "Poor Performance and Requiring Attention." This study aims to determine the handling priority for the irrigation networks at the Teurebeh Irrigation scheme. Data on irrigation network inventory was used as input. The determination of handling priority was conducted using the MannWhitney method. The ranking for determining the priority of irrigation assets is based on the condition and function of the irrigation assets. ArcGIS and Google Earth software were used to determine the condition and handling of all assets. The results show that the handling priority levels are between the primary and secondary channels. The priority for handling irrigation structure in the secondary channel is for two tapping structures, and one divider structure are ranked 1 to 3. They must be fixed immediately as severe to moderately damaged conditions are not functioning correctly. Furthermore, the priority for handling irrigation structure in the primary channel is for two bridges, and one divider structure are within priority 1 to 3. The Mann-Whitney test on the proposed hypothesis comparing the urgency level between the two channels is insignificant, indicating no significant difference between the handling of primary and secondary channels, as both have similar conditions and functions. The results are expected to contribute to decision-making at the Irrigation Department in designing proposals for renovating irrigation networks
ZnO Production from EAF Solid Waste Using Hydrothermal Methods via Oxalate Precipitation
Full text linkElectric Arc Furnace (EAF) waste contains 50-60% Zn. EAF waste synthesis has the potential to produce ZnO, which can be used in a variety of applications. The hydrothermal method is used in the synthesis, with time variations of 3 and 6 hours and temperature variations of 120 C, 150 C and 200 C using precipitating reagents in the form of sodium hydroxide (NaOH) and oxalic acid (C2H2O4). UV-Vis spectrophotometer characterization result shows the absorbance value at 365 nm, which is the absorbance characteristic of ZnO material. The result of increasing the Zn element was revealed by XRF characterization. The XRD characterization revealed zinc oxalate dehydrates. This result depicts the hydrothermal with the oxalic acid solvent used to produce zinc oxalate dehydration at various temperatures and time variations
Impact of Natural Pozzolan And The Degree of Circularity of Aggregates on The Thickness, Strength and Durability Of ITZ in Concrete ( Modeling and Experimentation)
Full text linkThe interfacial transition zone (ITZ) significantly negatively impacts the structural performance of concrete. This negative impact can be ameliorated by introducing mineral additions into the concrete. In this study, different forms (degree of circularity) of coarse aggregates and three contents (10%, 15%, and 20%) of mineral addition (natural pozzolan) were used to prepare ordinary concrete. This article aims to determine the optimal and effective mixture (the best form of aggregate and addition). This article aims to determine the optimal and efficient mixture (the best form of aggregate and addition) based on mechanical (compressive strength) and chemical (immersion in 3.5 % H2SO4 solution) tests. Furthermore, the effect of the interaction between the aggregate and the modified cementitious matrix was analyzed and discussed using the scanning electron microscope (SEM). The results show that adding 20% pozzolana improves the aggregate/matrix transition zone, making it possible to develop a maximum compressive strength at 60 days (51 MPa). In addition, the effect of mineral additions varies depending on the shape of the coarse aggregate. Thus, effective numerical modeling of the compressive strength is based on the full factorial design approach, considering the degree of circularity of the coarse aggregates and the pozzolan content
Supply Chain Risk Mapping at ABC Cement Plant in Aceh, Indonesia
Full text linkSupply Chain Risk Management is an industry collaboration that works with partners in the supply chain system to implement a risk management process in dealing with the emergence of risks and uncertainties caused by logistics activities or other resources in the supply chain. Every industry deals with risk. This study aims to identify, classify, and map supply chain activities and their risks. In the initial stage, supply chain events are identified through interviews and brainstorming. Then, these events are portrayed in the supply chain map. Then, the risk identification stage used a rating scale to determine the level of likelihood and consequence based on three SCOR elements. There are 40 risk events in this study which are 13 risk events in the source section, 19 risk events in the make section, and eight risk events in the delivery section. Finally, it is necessary to calculate the value of the Risk Priority Index. The Risk Priority Index is the basis of the risk mapping stage. The risk map shows the urgency to treat each risk event
Quantifying the Seismicity Parameters of A New Model of Seismic Source Zone for Aceh and Surrounding Areas
Full text linkAceh is justified as one of the Indonesian provinces with a high level of seismicity. This high seismicity certainly has a severe negative impact on various aspects of human life in Aceh and the surrounding areas. Various types of efforts must be carried out to solve and mitigate the problem caused by any earthquake in Aceh and the surrounding areas. One aspect that can be carried out to minimize the hazards of seismic activity is the characterization of the source of the earthquake. This characterization can be used for various purposes for further seismic-related studies, including for studying seismic hazard analysis using the probabilistic seismic hazard analysis (PSHA) method. This research aims to determine the characteristics of the seismic source zones for Aceh and the surrounding areas. Based on the geological setting and seismicity catalog data of Aceh and the surrounding areas, a new model of seismic source zones was developed. This new model proposed that Aceh and the surrounding areas be divided into four zones, namely shallow background seismic source zones (divided into two source zones), two deep background seismic source zones, two megathrust source zones, and one fault zone, namely the Sumatra fault zone. The results of this study suggest that Zone I and Zone II of shallow background seismic source zones have a-values of 2.36 and 4.7, b-values of 0.545, and Mmax of 7.7 and 6.8. Deep background seismic source zone I has an a-value of 4.43 and a b-value of 0.9 with a maximum magnitude of 7 Mw. Meanwhile, deep background seismic source zone II has an a-value of 3.28 and a b-value of 0.755 with a maximum magnitude of 6.1 Mw. Megathrust seismic source zone I has an a-value of 3.53 and a b-value of 0.691 with a Mmax of 7.7 Mw. Meanwhile, the megathrust seismic source zone II has an a-value of 3.81 and a b-value of 0.702 with a Mmax of 7.1 Mw. Sumatra fault seismic source zone has an a-value of 2.88 and a b-value of 0.615 with a Mmax of 6.7 Mw
Dynamic Green Function Solution of Beams Under Moving Loads With Elastically Supports
Full text linkThe dynamic analysis of bridges simulated as Euler-Bernoulli beam models with elastic supports subjected to mobile loads are analyzed by conventional methods to obtain a new solution for displacement. Generally, these beam supports can be characterized by springs with a given stiffness, which considerably influence the structure's dynamic behavior and even attenuate the dynamic amplification. The solutions proposed until now are defined only on span but not supports. In this paper, we used Green's function, considering boundary and continuity conditions and shear force to study the global behavior of the beam. A new displacement formula is proposed for the beam to support a span according to the velocity of the mobile load, the beam rigidity, and the stiffness of supports. A further study leads to the present two new formulas, which directly give displacements at the level of supports according only to the beam rigidity and supports stiffness and to the load value at any time. The result of this analysis shows that several combined factors influence the vibratory behavior of the beam when it is supported on elastically supports, namely the stiffness of the supports, the rigidity of the beam, its length, the value of the mobile load, and its velocity. The evolution of support stiffness leads to classical boundary conditions. A study of coupling between the beam and supports is presented, with the study of the comportment in function to the ratio between the beam rigidity and spring stiffness
A Unique Volcanic Jatibarang Reservoir: Facies Characterization and Fracture Calculation
Full text linkJatibarang structure, situated in Jatibarang low, one of the prolific sub-basin in the northwest Java basin, belongs to PT. Pertamina EP working area. One hundred seventy wells have been drilled, from which there were 56 production wells. Forty production wells were sunk on a volcanic reservoir. Since 1970, volcanic Jatibarang has faced disputed facies concepts, porosities heterogeneity, and permeability system. A fractured reservoir model was proposed. It was due to unique high-performance hydrocarbon in the early years, steeply depleted in the next 3 years, and flat over 20 years. A unique petrophysical method was developed with various explosives and effusive facies. This study proposes a new facies determination concept related to unavailable default petrophysical plots usually used in the clastic-carbonate reservoir. The new concept of formation evaluation attempts to distinguish the fractured vitric tuff reservoir and non-reservoir zone, which is both effusive lava and explosive product. Reservoirs differed from common clastic-carbonate, typically high gamma-ray reservoirs due to potassium feldspar composition. The fracture existence is reflected by a sonic overrunning density log aligned with a deep resistivity pattern. The width of the fracture apertures was measured, and spacing intensities were calculated. Finally, fracture permeability was estimated comprehensively to describe reservoir performance. Property models built with only sonic and triple combo have been debatable; however, advanced logging of JTB-211 has proven this accuracy method
Natural Frequency Measurement of Modest Dwelling Houses
Full text linkAround 1000 to 4000 units of modest dwelling houses are annually built in Aceh Province. A modest dwelling house is a small type of house with limitations in space planning which is very suitable for small families with middle to lower incomes. This lower middle-class community is a group of people who are very vulnerable and will be very severely affected when a disaster occurs. A modest dwelling house is a one-story building with simple construction and structure in its physical form. On the other hand, Aceh is also one area that is very prone to earthquake disasters from along the subduction zone and Sumatran Fault. Therefore, measuring the frequency of a modest dwelling house is crucial to understanding all house elements' conditions. It is essential to estimate the integrity and safety of the house after an earthquake occurs. The method used in this research is using the field experiment method in the form of measuring the natural response of the building to vibration based on microtremor data. This study uses a seismometer. The data is stored in a data logger. The seismometer is placed on the floor of the house. Data collection is carried out when no major activities are around the house. Measurements were carried out for a minimum of 60 minutes. Computer analysis with specific parameters obtained using Geopsy software. The result of this study indicates that the dominant frequency of modest dwelling houses measured is around 2.99 Hz. The analysis results from the field experiment were validated using pushover analysis of the detailed engineering design data. The modeling results show that in the x-axis direction (parallel to the direction of the building), the frequency obtained is 7.14 Hz. Pushover analysis on the model with the y-axis direction (parallel to the side of the building) obtained a frequency of 7.46 Hz. This validation shows a huge difference between the frequency of field measurement results and computer modeling results. Many factors, including decreasing or degrading the concrete construction quality in the field, can cause this gap
Tensile Strength of Natural Fiber in Different Types of Matrix
Full text linkIn recent years, product-based products with low environmental impact have become one of the considerations in the construction structure. The attention of researchers toward the development of natural materials has been increasing. The use of natural fibers as composite materials for the strengthened structure has been studied. However, natural fibers are influenced by their hydrophilic nature and specific morphology. Thus, research on natural fiber composite materials still needs to be explored. This study evaluates the tensile strength of natural fiber composite materials based on the type of fiber, fiber layer used, and resin type according to ASTM D3039. The highest tensile strength was found in the epoxy resinbased matrix composite with three layers of abacaa fiber (SAAE-LP3) by 111.45 MPa. The results show that the type of fiber, fiber layer used, and resin in the composite matrix considerably affect its tensile strength performance
Functional Group Structure of Bamboo and Pine Wood Biochar Due to Differences in Pyrolysis Temperature
Full text linkThe quality of biochar produced through the pyrolysis process depends on the combustion temperature, duration of combustion, and the raw materials used. Biochar is a carbon-rich product resulting from the thermal decomposition of organic matter. Biochar from bamboo and pinewood was produced at 400 and 800 using a closed chamber where the temperature could be set. Biochar is made through carbonization with pyrolysis. This study aimed to find out the functional group characteristics of two types of raw materials, bamboo and pine wood. This research was conducted at the Environmental Soil Physics Laboratory, Universitas Syiah Kuala. Two types of feedstocks, bamboo, and pinewood, were used as sample experiments. The feedstocks were burned inside a closed chamber with no oxygen present. (Thermo scientific thermolyne F4820-33). The temperature was at 400 and 800, and a burning time of four hours. Fourier Transform Infra-Red (FTIR)was used to characterize the functional groups of biochar tested. Our research showed biochar from pinewood burned at a temperature of 400 gave the characteristics of the functional groups OH, CH, and C=O with strong intensity. It indicates that there was decomposition of organic matter into organic compounds taking place