Mechanical Properties of Granite-Gravel Porous Concrete

The need for porous concrete has become increased due its ability to control surface water, increase the rate of recharging groundwater, and reduce pollution of the ecosystem. Granite is a coarse aggregate that is quite expensive when compared with gravel in Nigeria. Therefore, this research is aimed at optimizing blended granite and gravel in the production of porous concrete. Samples of blended granite-gravel porous concrete of varying mix proportions were produced using cement to aggregate mix ratio of 1:4. The samples were tested for their porosity, workability and compressive strengths. The data collected were analyzed with the aid of Design Expert 10.0. It was observed that the optimal combination for the granite-gravel blended porous concrete is 12% granite, 88% gravel, and a water-cement ratio of 0.66%. This combination gave a porous concrete with a compressive strength of 48.4 N/mm2, percentage porosity of 6% and a compacting factor of 0.91. These values when compared to that of the control specimen revealed that the optimal mix gave a porous concrete with higher porosity, higher workability and a better compressive strength.

Kualitas Batugamping Gorontalo Sebagai Reservoir Air Tanah Berdasarkan Analisis Jenis Porositas

The potential of limestone in Gorontalo City is not only the use of industrial minerals but also its availability as a reservoir of groundwater reservoirs. The availability of groundwater is the main focus in preserving the environment. For this reason, this research focuses on the quality of limestone reservoirs by analyzing limestone porosity. The purpose of this study was to determine the average porosity percentage, porosity type and porosity quality both semi-quantitative and qualitative. In order to achieve these objectives, two methods are used namely the field survey method and petrographic analysis. The results showed the average percentage of porosity quality of limestone as a reservoir of groundwater in the excellent category with the type of porosity is fracturing and growing (vugular).

Effect of Ceramic Waste Aggregate in Concrete to Reduce Environmental Pollution

The utilization of ceramic waste is one solution to reduce environmental pollution due to development waste. The aim of this study was to utilize ceramic waste as a concrete aggregate material. The test consisted of the mechanical properties test of ceramic waste aggregates and the compressive strength test of ceramic concrete. The variation of normal aggregate partial replacement with the aggregate of CWA is 0%, 25%, 50%, 75%, and 100%. The total number of specimens is 50 cylinders. From the results of material testing and ceramic concrete tests showed that ceramic waste aggregate can be used as concrete aggregates, especially for elements that accept compressive forces, shear forces, and in-plane forces. The X-ray test shows that CWA aggregate is not pozzolanic, so it can be used as a concrete aggregate to reduce environmental pollution. The percentage porosity of ceramic concrete is smaller than the porosity of normal concrete. The effect of partial replacement of normal aggregate with the CWA aggregate in concrete optimum at a value of 55% CWA aggregate.

The Characteristics and the Concept of the Utilisation of Post-Production Calcareous Waste Deposited in Landfills

This article presents the results of research into calcareous waste from the production process of oxide propylene. The obtained results show a considerable chemical diversity of calcareous waste with a predominant percentage share of Ca, C and Cl, which are the products of the process. It was shown that the share of calcium bonded in CaCO3was over 20%, which is indicative of the secondary carbonisation process taking place in the waste. The morphological and structural analyses revealed that the grains had a surface area above 12% and a percentage porosity in the range of 25-35%. The reactivity test made it possible to classify calcareous waste as a material for sorbents of 'satisfactory' sorption properties, insufficient to be effectively used in the power sector. For the stored waste to be reused, it is necessary to improve its sorption abilities through the application of a properly selected activation method.

ANALISIS KUANTITATIF PORI BERDASARKAN PENGOLAHAN CITRA MENGGUNAKAN WOLFRAM MATHEMATICA

<p><em>Currently, a porous material has been extensively developed in many areas of applied science and engineering. The characteristics of porous material is most often determined by its porosity. In this paper, we present a quantitative analysis of pores in a material according to image processing methods. An micrograph from electron microscopy (SEM) was analyzed by using Wolfram Mathematica. From our study can be obtained some informations about pore percentage (porosity), pore size, ratio aspect, and distribution of pore size in the materials.</em></p><p><em><strong>Keywords</strong></em><em>: pore, image processing, Wolfram Mathematica</em></p><p><em><br /></em></p><p><em>Saat ini, material berpori telah dikembangkan secara luas di banyak bidang sains terapan dan teknik. Karakteristik dari material berpori seringkali ditentukan oleh porositasnya. Dalam makalah ini, kami menyajikan menyajikan analisis pori dalam suatu material berdasarkan metode pengolahan citra. Suatu mikrograf dari mikroskopi elektron (SEM) kami analisis dengan menggunakan Wolfram Mathematica. Dari penelitian kami dapat diperoleh beberapa informasi tentang persentase pori (porositas), ukuran pori, aspek rasio, dan distribusi ukuran pori dalam material.</em></p><p><em><strong>Kata kunci</strong></em><em>: pori, pengolahan citra, Wolfram Mathematica</em></p>

Hemodialysis Membrane Prepared from Bacterial Cellulose/Lithium Chloride/N,N-Dimethylacetamide Solution

A new bacterial cellulose regenerated cellulose membrane (RBC) has been prepared by phase inversion method in LiCl/DMAC solution. The effects of coagulation concentrations on the physical properties of the RBC membranes were studied and optimized. Features of the RBC of membranes obtained using 0%~40% N,N-Dimethylacetamide (DMAC), such as water absorption percentage, porosity (Pr), ultrafilter rate (UFR), and tensile strength were investigated. The RBC membranes prepared with 40% DMAC solution as coagulant exhibit a smooth surface and a high tensile strength with suitable UFR. RBC showed improved permeabilities for urea and vitamin B12when compared with commercial cellulose membranes.