Composite foundations on Malaysian soft clay soil: applications of innovative techniques

An innovative technique of electro osmosis coupled with vertical surcharge loading to accelerate the consolidation and stiffen Kaolin (China Clay Grade E) was investigated in this study. The geotechnical properties of this China Clay Kaolin Grade E and the design of electro osmotic consolidation chamber are discussed together with an explanation of the procedural concept of the electro osmotic consolidation chamber (i.e., the preparation of the apparatus and the clay sample, assembling of the electro osmotic consolidation chamber; and the experimental work). The plastic limit, liquid limit and plasticity index were 35%, 53% and 18% respectively. Therefore, China Clay Kaolin Grade E is classified as MH soil, and it is predominantly a silt with high plasticity. The specific gravity of the soil is 2.65. To ensure the kaolin is saturated, all samples were prepared in a similar manner with deaired water to produce a slurry at 150% of the liquid limit (initial moisture content of 79.5%). The electro osmotic consolidation chamber was cylindrical and consisted of the body, the base and the top cap. The body and the base of the chamber were constructed of polyvinyl chloride (PVC) tube with a wall thickness of 10.9 mm, 345 mm high and 251 mm inner diameter. The electro osmotic consolidation chamber was assembled together with a 45 mm thick flange and collar. The top cap of this chamber was based on that of a Rowe cell of similar diameter. Twenty one tests were performed in this study with an applied voltage and one test was a control test. The test samples in the twenty one tests were all consolidated to three different phases. In Phases 1 and 2, the samples were consolidated at 15 kPa while in the Phase 3, 50 kPa was used. The electro osmotic process was only performed during Phase 2. The time of treatment, numbers of electrodes, the arrangement of electrodes, and the applied voltages were investigated in these tests. Results from these tests indicated that the China Clay Kaolin Grade E in a 79.5% slurry form responded well to electro osmotic treatment and that electro osmotic process increased the overall stiffness of the soil as indicated by the reduced relative settlement in Phase 3 with a pressure of 50kPa. The water content around the anodes was less than that at the cathode creating zones of higher average constrained stiffness. The tests demonstrated that the longer the time of treatment, the greater the numbers of anodes, the shorter distance between the electrodes and the higher the applied voltages associated with electro osmosis increased the average stiffness of the soil mass confirming the concept of an electro osmotic pile. Keywords: electro osmotic merged vertical loading and electro osmotic, consolidation, electro osmotic consolidation chamber, stiffening

POLYCARBONATE WITH FUNCTIONALIZED GRAPHITE NANOFIBERS (GNF) AND THE STUDY OF ITS THERMAL AND MECHANICAL PROPERTIES

The present study described the process of producing polycarbonate with functionalized graphite nanofiber (GNF) composite and its properties. To improve the solubility of GNF, it will have to go through functionalization which is also known as oxidation. Before functionalization, the GNF have to undergo acid wash process to eliminate metal catalyst in the raw GNF at the same time removing impurities and increase the purity. Acid wash was done by using 2 Molar (M) ofhydrochloric acid and 1hour ofstirring using a mechanical stirrer. After metal elimination process, the GNF was functionalized for 4 hours in 4M nitric acid by using double sonication system; which was using both ultrasonic bath and ultrasonic probe at the same time, to increase efficiency. The acid treatment chemically modified the hydrophobic and inert nature of the surface of raw GNF by attaching functional group such as carboxyl group (COOH) which were detected by using Fourier Transform Infrared Microscopy (FTIR) analysis. The morphology and surface of the GNF were studied from Field Emission Scanning Electron Microscopy (FESEM). Then, the enhance polymer plastic were prepared by solution blending method. Dispersion of GNF within the polymer was observed by microscopic imaging. The study then investigated into the mechanical and thermal properties of the polycarbonate-GNF by Thermo Gravimetric Analysis (TGA) and Universal Testing Machine. For this research, 0.5wt% gives the better dispersion without aggregation and a significant increase in the properties compared to the samples of lwt% and 2wt% where the fibers agglomerate; decreasing the nano-composites potential

Nanotechnology for wireless gas sensor

Gas sensor are increasingly being employed, not only in industrial settings and also in every aspect of human life, where they are telling something about their environment by bridging them with the electronic world. Sensors are used to gather a wealth of information from the process that can improve operational efficiency and product quality which involving a mass of data that need to be analysis especially with the merging of the Internet of Things (IoT). They included with new features such as communication capability and on-board diagnostics. Meanwhile, leading edge research in sensors has been propelled by the advancements made in fabrication, signal processing and nanotechnology in the last decade. With these the scientific world is now on the verge of delivering sensors with radically new capabilities for the human societies. This talk deals with the future trend in sensor technology especially for wireless gas sensor and several researches works in Universiti Putra Malaysia related with them