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Problem statement: Mortar mix is a major construction material in fabr ication of ferrocement structural elements. However, there have been scarc e amount of technical data available on suitable mi x proportion to achieve structural grade mortar with specific strength requirement and adequate level of workability for proper placement into construction formwork. Moreover, current practice in ferrocement construction work which uses mortar mix with cement: sand ratio ranging between 1:1.5 to 1:2 incurs hi gh requirement of cement yet producing mix with suboptimum level of compressive strength. Approach: An experimental investigation was carried out to evalu ate workability and compressive strength properties of structural grade mortar mixes with various cement: sand ratios ranging from 1:2.0-1:2.75 and varying water/binder ratio between 0.35 and 0.50. Throughout the laboratory investigation, a total of 28 batch es of mortar mixes with various mix proportion were designed, cast and tested in accordance to relevant stan dards of practice prescribed by British Standard Institut e (BSI) and American Society of Testing Material (ASTM). Results: At the end of the laboratory investigation program, high performance mortar mix with compressive strength exceeding 55 MPa and slump level within 50-90 mm which is suitable for heavy duty ferrocement construction work was successfully developed. Moreover, data on mix proportion for several other grades of mortar mixes ranging from grade 35 to grade 55 were also derived. Conclusion: It was found that optimum cement: Sand ratio of structural mortar is 1:2.25. With the use of this cement: San d ratio in the production of structural grade mortar mix in fabrication of ferrocement structural elements, consumption of cement binder will be economized hence resulting in potential savings in term of materi al and production cost of mortar mix in the constructi on industry. Besides, it was also observed that str engths of mortar mixes do not vary linearly with cement co ntent of the mix.

Problem statement: It was the aim of the study to analyze the level o f performance of natural air ventilation with a case study of the tr aditional Malay house in Penang, Malaysia. This stu dy provided information on the architectural design in relation to natural air ventilation. It promoted passive design in contrast to most housing design w hich has poor natural air ventilation because the design was orientated to energy consumption that sl ightly more than one third of the electric energy was used for heating, ventilating and air condition ing systems. Approach: This analysis used quantitative method which measured temperature, humidity and wind speed of the traditional house. The result indicated the level of performance of cr oss air ventilation and stack effect. Results: The analysis showed that the traditional house has a de sign integrated with natural air ventilation system . The indoor house temperature and relative humidity had slightly lower than its outdoor area. However, the indoor area had lower wind speed level than the outdoor area. Conclusion : The study showed that maximum openings on the building walls created high air intakes outside the house to give poor performance of stack effect. The design had more emphasis to cross air ventilation.

Problem statement: Researches has been conducted worldwide on a large number of natural or artificial lightweight aggregates. In spite of many of the researches of using natural fibers show considerable promise, the use of natural fibers to improve the properties of lightweight concrete still required to be a subject of further research and investigation. Approach: This experimental investigation was carried out to study the properties of lightweight crushed brick concrete containing palm fiber of different volume fractions. An experimental programme was planned in which the tests such as density, compressive strength and flexural strength were conducted to investigate the properties of lightweight crushed brick concrete reinforced by palm fiber. The specimen incorporated different volume fractions of palm fiber, i.e., 0, 0.2, 0.4, 0.6, 0.8 and 1.0%. Results: Tests results showed that the use of this fiber slightly increases the density of lightweight concrete. The use of 0.8% of palm fiber increases the compressive strength and flexural strength by about 13.4 and 16.1% respectively. Conclusion: The results indicated that the use of palm fiber with lightweight crushed brick concrete enhances the mechanical properties of the concrete and the optimization of the palm fiber fractions is required to get the best performance.