Volume 15 (2003)
Table of Contents
Table of Contents
|1.||Ramalan Kekuatan Tegangan Pecah Konkrit Prestasi Tinggi (Prediction of Splitting Tensile Strength of High Performance Concrete)
Muhammad Fauzi Mohd. Zain, Ade Ilham, Hilmi Mahmud, Wan Hamidon Wan Badaruzzaman, Faizal Mahmud & Kamarudin Mohd YusofAbstract
Splitting tensile strength is one of the concrete mechanical properties that is used in structural design. It can be related to numerous parameters which include compressive strength, water-binder ratio and concrete age. Until now, most researchers estimated the splitting tensile strength (STS) directly from compressive strength data. This paper suggests formulae that relate splitting tensile strength with that of compressive strength, water-binder ratio and concrete age. The predicted STS can be obtained accurately using these formula. It is proposed that the equation with the concrete age (t) parameter be used in predicting the splitting tensile strength of high performance concrete.
|2.||Experimental and Analytical Fatigue Data for Notched Shafts in Bending
Ali-Reza Gowhari-Anaraki, Hardy, Stephen John & Mohammad Kazem PipelzadehAbstract
An experimental investigation has been carried out on two types of shaft with different stress concentration features in order to determine the notched members fatigue life in bending. The shafts are made from steel with DIN specification CK45, which is widely used for machinery components. These lives are compared with estimates using the simple notch-stress-strain- conversion rules (e.g., Neuber; Linear) and the strain energy density methods in conjunction with the Coffin-Manson strain life relationship. The paper demonstrates the simplicity and accuracy of the approach although the predictive capability was found to depend on the magnitude of the elastic stress concentration factor.
|3.||Penggunaan Abu Bakaran Klinikal di Dalam Konkrit Prestasi Tinggi (The Use of Clinical Ash in High Performance Concrete)
Mardalena, Muhammad Fauzi Mohd. Zain & Hassan BasriAbstract
The use of waste materials such as municipal solid waste, industrial waste, and hospital waste for beneficial purposes is an appropriate choice, because it will reduce the need for landfill space. To reduce the volume of materials waste, the most effective method is incineration. It can reduce the volume of waste up to 90% and will produce two by-products, namely bottom-ash and fly ash. This research uses fly ash from Tongkah Medivest Sdn. Bhd. clinical waste incinerator as clinical ash. It is used as cement replacement material at 5%, 10%, 15%, 20%, 25%, 30%, and 35% for making high performance concrete. The concrete were designed at water-binder ratio of 0.35 and 0.50. Water curing and air curing were practised. Compressive strengths were determined at the age of 7, 14, 28, 56, 90, and 180 days. The result showed that the compressive strength of 0.35 water-binder ratio under both curing methods produced higher strength. The compressive strengths of concrete were decreased as the percentage of clinical ash increased. The concrete that contained 5% clinical ash showed the highest value of compressive strength compared to others. Therefore, from the perspective of compressive strength, clinical ash can be used in concrete.
|4.||Penilaian Kawalan Lampu Isyarat Terpisah Berbilang Kaedah (Evaluation of Separate Traffic Light Control Multiple Method)
Atiq O.K. Rahmat, Kasmiran Jumari, Azmi Hassan & Hassan BasriAbstract
It is frequently observed that the queue lengths on the approach roads at a signalised intersection are imbalanced during peak hours and in many cases traffic marshall has to control the intersection manually. This problem is partly due to the inability of the conventional system to be optimised and to get the actual traffic demand. To overcome these two problems, the traffic control system developed in this project adopts vehicle actuated control, optimised control and traffic marshall emulation control during low, high and congested traffic demand respectively. The system utilised a video detection system as the sensor to detect the real traffic demand. Experimental data show that the control system. is found to reduce the sum of queue length 33% as compared to the conventional system. During congested period proposed system reduced queue length by 9% and delay by 10% as compared to manual control by traffic marshall.
|5.||Penggunaan Algoritma Genetik bagi Menentukur Model Anjakan Mod Pengangkutan (Application of Genetic Algorithm for Calibration of Modal Shift Transportation Model)
Siti Hajar, Riza Atiq, Amiruddin Ismail & Hassan BasriAbstract
The Logistic model is frequently used for modeling transport modal shift. Logarithmic transformation together with linear regression are usually used to calibrate the model. However, the problem with logarithmic transformation is that a large difference between data sets of a few thousand times would become small. Therefore, genetic algorithm is used to calibrate the Logistic model because of its ability to solve complex problems efficiently and suitability for solving multi variate non-linear problems. In this study, genetic algorithm is based to calibrate modal shift model from private cars to buses. The result of this study has shown that the calibrated model is highly correlated to the actual modal shift with correlation greater than 98%.
|6.||Finite Element Analysis on Drawing of Copper Wire Containing an Inclusion and A Cavity
Somchai Norasethasopon & Kazunari YoshidaAbstract
In this paper the influence of an eccentric inclusion and cavity on copper shaped-wire drawing were investigated. An experimental investigation for optimal die half-angle was conducted. Based on experimental data of optimal die half-angle, the deformations, the mean normal stress and the plastic strain of both copper shaped wires containing an eccentric inclusion and cavity were calculated by finite element analysis. The same parameters for both copper shaped-wires containing a centric inclusion and cavity were also calculated using the same method. Necking, bending and misalignment were observed during drawing of a wire containing an eccentric inclusion. However only necking was observed during drawing of a wire containing a centric inclusion. It was found that the inclusion rotated during drawing and extremely compressive stress occurred on the die contact surface during drawing of wire containing eccentric inclusion. For the same inclusion size, the drawing stress was strongly .influenced by inclusion size and slightly influenced by eccentric length. The drawing stress of wire containing centric inclusion was greater than that of wire containing eccentric inclusion. It was found that the drawing stress decrement was due to- a cavity and the deformation behaviour of a wire containing a cavity was opposite to that of a wire containing an inclusion.
|7.||Formulasi Faktor Kualiti Bagi Permarkahan Lukisan Kejuruteraan (Formulation of Quality Factor for Engineering Drawing Scoring)
Yuwaldi Away, Zarina Shukur, Mohd Juzaidin Abdul Aziz & Mohammad Asmady DawariAbstract
This work describes the design and implementation of an instrument for assessment that would enable Mechanical Engineering Drawing (MED) to be evaluated automatically by using the computer. A prototype of the Computer- Aided Marking System For Engineering Drawing System (CAMSEDS) could ~place the existing manual marking process. The CAMSEDS framework begins from the display of objects that are generated from the lecturers’ and earners’ AutoCAD 2000 drawings that have been changed into the DXF files. The geometrical data are extracted and analyzed by comparing geometrical rata from the lecturer’s and the learner’s drawing automatically or a semi- automatically for similarities and differences between them. In CAMSEDS, the empirical data is compared in order for the system to automatically evaluate based on the following criteria: drawing entity, the entity of object accuracy and the accuracy of measurement. The semi-automatic analysis also involves manual assessment to evaluate the accuracy of a design based on visual I how that CAMSEDS prototype would help in reducing marking errors, in comparison to the present manual assessment via computerized MED. The formulas for quantitative assessment that have been proven effective in making CAMSEDS assessment more relevant and consistent are (1) formulation of assessment for drawing entity (2) formulation of assessment for the entity of object accuracy. (3) formulation of assessment for the accuracy of measurement, and (4) formulation of assessment for visualition.