Juliana Anggono

Effects of Calcination Temperature of LUSI Mud on the Compressive Strength of Geopolymer Mortar

The abundant availability of LUSI (a short form of LUmpur SIdoarjo or Sidoarjo mud) mud of a mud volcano located in Sidoarjo, East Java, Indonesia, attracts interest of researchers to seek the possibility of utilizing it; among them is as construction material. This study focuses on the effect of calcinations temperatures of LUSI mud on the compressive strength of geopolymer mortar. Three different calcinations temperatures were investigated, i.e. 700, 800 and 900°C for five hours duration. Characterization of the mud, both the original and the calcined ones, was performed by using X-ray Diffraction (XRD) and X-ray Fluoresence (XRF) analyses. The calcined LUSI mud was then employed as precursor for making geopolymer mortar, and tested for its 7-day compressive strength. It is found that calcinations at 800°C is the optimum calcinations temperature producing the highest compressive strength.

The use of sugarcane bagasse in PP matrix composites: A comparative study of bagasse treatment using calcium hydroxide and sodium hydroxide on composite strength

Sugarcane fibers have been studied as reinforcement fibers to develop biocomposites of sugarcane fibers-polypropylene (PP). In this study, two different alkaline solutions were used to modify the sugarcane bagasse fibers, i.e. 10% v/v NaOH and 14% v/v Ca(OH)2 solution for 4 hours. Sugarcane fibers filled to polypropylene (PP) matrix was 3 cm, 5 cm and as their original length. They were added in the various weight percentage ratios between sugarcane fibers to PP of 20/80, 25/75, and 30/70. Fourier-Transform Infrared (FTIR) spectroscopy was used to study the chemical structure of bagasse fibers after treatment. Composite strength was measured by tensile test which was performedin accordance with ASTM D638-03. The fracture surface of tensile tested composite specimens contained fibers from both treatment was evaluated using Scanning Electron Microscope (SEM). Results from the tensile test show that performing NaOH treatment for 4 hours could increase the tensile strength of the composites to 24.92 MPa when ...

Effect of Alkali Treatment Using Calcium Hydroxide and the Fiber Length on the Strength of Sugarcane Bagasse Fibers-Polypropylene Composites

Milling sugarcanes to produce sugar generates by-product called bagasse. Due to the large availability and low cost, the potential of obtaining renewable and biodegradable fibers from bagasse had been explored. To produce fibers from these bagasse, the bagasse was treated in alkali solution using 14 % v/v calcium hydroxide, Ca (OH)2 at high temperature (60-70°C) for 4 hours. After treatment and washed to remove dissolved substances, the fibers were cut into 3 and 5 cm length. Some fibers were prepared in their original length. These fibers were mixed with polypropylene (PP) matrix in weight % ratios of bagasse fibers/PP 20/80, 25/75, and 30/70 and hotpressed to make composite samples. Composites produced were characterised with tensile test to evaluate their tensile properties. Scanning electron microscopy (SEM) was performed on the fiber surface as well as on the fracture area of the tensile tested samples. Tensile strength of the composite shows an increase with the increase of the fiber length and weight % ratios of bagasse fibers/PP up to 25/75 and decreases when bagasse fibers were added to 30 wt.%. The highest strength of 11,30 MPa was obtained when 5 cm fibers were used in a weight % ratio of bagasse fibers/PP at 25/75. SEM study found a greater number of fibers oriented perpendicular to the tension direction.

Performance and Evaluation of Low Cost Sugarcane Bagasse - Polypropylene Biocomposites as Candidate Material for Automotive Parcel Tray

Many auto manufacturers such as Mercedes Benz, Toyota and DaimlerChrysler have already embraced natural fiber composites into both interior and exterior parts and are looking to expand the uses of this composites. They have to balance the changing public demands of greater comfort, better driving performances, and higher safety standards with the environmental requirements. Based on the preliminary study using 20 to 30 wt.% NaOH treated sugarcane bagasse fibers to make biocomposites with polypropylene matrix, the tensile strength obtained was variably, in the range between 8.31 to 20.59 MPa. A further study was required to improve the strength of the composites in comparison with the specified flexural strength required by the industry for automotive parcel tray. The sugarcane bagasse fibers obtained from the sugar mill were used and alkali treated with 10% v/v NaOH at various soaking time of 2, 4, and 6 hours. Biocomposite samples were prepared from 25/75 wt.% ratio sugarcane fibers/polypropylene (PP). The highest tensile strength of 14.35 MPa was obtained from the samples with sugarcane fibers receiving two-hour alkali treatment. However, the highest flexural strength (37.78 MPa) was gained on the samples made from sugarcane fibers with 4 hours alkali treatment. This value has met the strength specification of two materials for current parcel trays which were made from monomaterial of polypropylene and woodboard composite which their flexural strengths were 35.6 MPa and 37.57 MPa, respectively. Structural studies using scanning electron microscopy (SEM) on the fracture surface of tensile tested samples show two different orientations of bagasse fibres in PP matrix, i.e. a group was in longitudinal orientation and other in transversal orientation.

Open windows for natural airflow and environmental noise reduction

ABSTRACT For buildings in tropical climates, the use of open windows for natural ventilation can not only provide low cost and low energy comfort but also provide thermal delight for occupants. However open windows let in environmental noise. The size and location of windows in walls are key but this study set out to determine whether there are any window forms that can effectively reduce the level of sound ingress into a building. A top-hung window was chosen for this study looking at the dimensions of the window opening and its orientation in relation to the environmental noise source. The top-hung form was selected for its potential to balance the functions of allowing airflow while potentially blocking and reducing noise levels with its window pane angle. The window pane was tested in a laboratory at three opening angles: 0° (closed), 5°, and 10° to let the outdoor air in. The angles were also tested in three different orientations in relation to the noise source position: perpendicular, sideways 60°, and sideways 90°. The test was conducted at 1/3 octave band frequency as specified by ASTM E90-09 to obtain the transmission loss, then ASTM E1332-90 was referred to calculate the outdoor-indoor transmission class (OITC) of the specimens. The study revealed that window orientation and extent of the openings and window pane angle have little effect on noise reduction. The paper concludes with a discussion of how higher levels of natural ventilation can be achieved, particularly in noisy urban areas. The top-hung window, once open, barely blocks environmental noise. However, when the window was closed, the perpendicular orientation offered more noise reduction when compared windows placed sideways to the noise source. The adjustable pane-angle of a top-hung window placed perpendicular to the airflow, and thus the noise source, seemed to have the most potential to balance the functions of allowing airflow when opened and reducing significant noise when closed. Nonetheless, an open window that through its design alone can significantly reduce the ingress of ambient noise into a building is still an issue.

The effect of orientation difference in fused deposition modeling of ABS polymer on the processing time, dimension accuracy, and strength

There are several parameters that must be set before manufacturing a product using 3D printing. These parameters include the orientation deposition of that product, type of material, form fill, fill density, and other parameters. The finished product of 3D printing has some responses that can be observed, measured, and tested. Some of those responses are the processing time, the dimensions of the end product, its surface roughness and the mechanical properties, i.e. its yield strength, ultimate tensile strength, and impact resistance. This research was conducted to study the relationship between process parameters of 3D printing machine using a technology of fused deposition modeling (FDM) and the generated responses. The material used was ABS plastic that was commonly used in the industry. Understanding the relationship between the parameters and the responses thus the resulting product can be manufactured to meet the user needs. Three different orientations in depositing the ABS polymer named XY(first orientation), YX (second orientation), and ZX (third orientation) were studied. Processing time, dimensional accuracy, and the product strength were the responses that were measured and tested. The study reports that the printing process with third orientation was the fastest printing process with the processing time 2432 seconds followed by orientation 1 and 2 with a processing time of 2688 and 2780 seconds respectively. Dimension accuracy was also measured from the width and the length of gauge area of tensile test specimens printed in comparison with the dimensions required by ASTM 638-02. It was found that the smallest difference was in thickness dimension, i.e. 0.1 mm thicker in printed sample using second orientation than as required by the standard. The smallest thickness deviation from the standard was measured in width dimension of a sample printed using first orientation (0.13 mm). As with the length dimension, the closest dimension to the standard was resulted from the third orientation product, i.e 0.2 mm. Tensile test done on all the specimens produced with those three orientations shows that the highest tensile strength was obtained in sample from second orientation deposition, i.e. 7.66 MPa followed by the first and third orientations products, i.e. 6.8 MPa and 3.31 MPa, respectively.There are several parameters that must be set before manufacturing a product using 3D printing. These parameters include the orientation deposition of that product, type of material, form fill, fill density, and other parameters. The finished product of 3D printing has some responses that can be observed, measured, and tested. Some of those responses are the processing time, the dimensions of the end product, its surface roughness and the mechanical properties, i.e. its yield strength, ultimate tensile strength, and impact resistance. This research was conducted to study the relationship between process parameters of 3D printing machine using a technology of fused deposition modeling (FDM) and the generated responses. The material used was ABS plastic that was commonly used in the industry. Understanding the relationship between the parameters and the responses thus the resulting product can be manufactured to meet the user needs. Three different orientations in depositing the ABS polymer named XY(first o...