Abdul Naser Abdul Ghani

COOLING EFFECTS OF TWO TYPES OF TREE CANOPY SHAPE IN PENANG, MALAYSIA

Shade trees provide a cooling effect by blocking sunlight, increased ambient air humidity and provide shade during the day. All trees cannot offer relief from the heat in the same amount. This study compared the shading effectiveness of two types of canopy shape (rounded and spreading) in the landscape of Universiti Sains Malaysia, Penang. There are four species selected for this study. Field measurement of microclimate conditions under the tree canopy and open spaces were repeated on a sunny day. The effect of trees shade on air temperature, surface temperature, relative humidity, solar radiation and solar transmission were also compared and related to the leaf area index (LAI). It was found that the air temperature under the canopy could be reduced between 0.67 °C to 2.55 °C, while the surface-soil temperature can be reduced between 3.23 °C to 8.15 °C. Tree species with higher LAI values, Swietenia macrophylla (Big leaf mahogany) and Tabebuia rosea (Tecoma) provide significantly more cooling than the other species. Reduction of surface temperature is positively correlated with leaf area index. This study shows that shade tree in tropical climates are helpful in improving the outdoor thermal comfort, cooling ground surface by encouraging more latent heat and reduces air temperature by encouraging more evapotranspiration. Thus, the selection of tree species with higher leaf area index value can maximize the benefits they provide to the surrounding area.

An overview of road damages due to flooding: Case study in Kedah state, Malaysia

Flooding occurs frequently in many countries including Malaysia. Floods in Malaysia are usually due to heavy and prolonged rainfall, uncontrolled development, and drainage systems that are not being monitored. Road damage due to flooding event can cause huge expenditures for the post-flooding rehabilitation and maintenance. The required maintenance and rehabilitation could upset the original life cycle cost estimations. Data on road statistics were obtained from the Highway Planning Division, Ministry of Works Malaysia and data on flooding was collected from the Department of Irrigation and Drainage Malaysia for events between 2012 and 2015. The pilot sites were selected based on its historical cases of floods that caused road damages in Kedah. The pilot site indicated that the impact of flooding on road infrastructures systems can be used to plan better road design and maintenances. It also revealed that it costs more than RM 1 million to reinstate roads damaged by flooding in a typical district annually.Flooding occurs frequently in many countries including Malaysia. Floods in Malaysia are usually due to heavy and prolonged rainfall, uncontrolled development, and drainage systems that are not being monitored. Road damage due to flooding event can cause huge expenditures for the post-flooding rehabilitation and maintenance. The required maintenance and rehabilitation could upset the original life cycle cost estimations. Data on road statistics were obtained from the Highway Planning Division, Ministry of Works Malaysia and data on flooding was collected from the Department of Irrigation and Drainage Malaysia for events between 2012 and 2015. The pilot sites were selected based on its historical cases of floods that caused road damages in Kedah. The pilot site indicated that the impact of flooding on road infrastructures systems can be used to plan better road design and maintenances. It also revealed that it costs more than RM 1 million to reinstate roads damaged by flooding in a typical district annually.

The temperature effect to the concrete due to the single strike of high electric current

The protection against lightning had been increasingly used in the building to protect the building from the direct lightning impact. One of the methods is to embed the lightning protection cable in the concrete structure. The objective of this research is to investigate any changes of temperature during the lightning strike, which the lightning strike were stimulated by high electric current equipment. The high electric current were provided by high current equipment model Haefely P90.1 and flowed into the concrete cube. There are two method used in this research, by using Thermal Imager Camera Model FLUKE Ti20 to monitor the surface temperature and fiber thermocouple with Data logger model DATATAKER T80 to monitor the temperature in the concrete cube. As the result there are no drastically changes in temperature in both methods. The changes are very small and can be negliable. This is due to the duration of the high electric current strike is too short and not caused any changes in the temperature.

Permeable pavements and its contribution to cooling effect of surrounding temperature

Generally, the pavement surface temperature usually is higher compared to air temperature. It is caused by the absorption of solar energy onto the surface. The pavements temperature strongly influences the urban climate as an urbanization result. The increase of heat in the urban area are partly contributed by the pavement. Permeable pavement can be seen as a way of reducing the temperature of the pavement. This study reviews the existing technology and mechanism of permeable pavements cooling properties. There are various factors that could affect the pavement’s temperature such as the solar reflectance, thermal properties, permeability, evaporation and others. However, previous researchers have found out that, permeable pavement tends to be hotter than conventional pavement during dry seasons. It was found that the presence of water could reduce the temperature of the pavement. Future studies can be conducted towards finding ways to maintain the wet condition within the pavement.

Software Analysis of the Reinforced Concrete Beam with Additional Installation of Lightning Protection Cable

Lightning protection system protects building structure from direct lightning impact. Embedding lightning protection cable inside concrete structure is widely use in practice now days. The objective of this research is to investigate the effect of installation of additional conductor cable inside concrete beam to its beam displacement and beam stress using finite element analysis software ABAQUS. The beam without additional conductor cable, with cable conductor installed at top and bottom reinforcement is modelled using ABAQUS. The results obtained from the three model is compared. As the result, the beam with additional conductor cable at top reinforcement shows minimum deformation and minimum Mises stress.

Review of vibration effect during piling installation to adjacent structure

Basically, many major structures across the world such as towers, high rise building, houses and bridges utilize pile as a support material. The use of pile is important to strengthen the structures. However, this has led to another problem to the nearest surrounding structures resulted from pile driving. As part of a construction work, unavoidable pile driving activity generates a vibration towards the surrounding structures if uncontrolled may cause damage to the adjacent structure. As the current construction works are frequently located in urban areas where the distance between the nearest building structures is not far, vibration may cause damage to nearby structures. Knowing which part of the building that is mostly affected by various vibration patterns from the impact of pile driving is crucial. Thus, it is very important to predict the impact of vibration during piling installation work. This paper reviews the vibrations generated by piling activity toward surrounding structures in terms sources ...

STUDY ON THE USE OF OBSTRUCTING OBJECTS TO DIFFUSE FLOOD WATER VELOCITY DURING ROAD CROSSING

Laboratory experimental investigations were conducted to identify suitable shape and dimension of objects as well as its capability to reduce flow velocity. The first stage of the study was to identify suitable shape and its arrangement. In this test a scale of 1:20 was used in a flow table experiment. The water flow pattern was recorded focusing on the distance and amplitude of the pattern as water flow pass the obstructing objects. The second stage of the investigation involved a hydraulic model investigation. In this investigation, the velocity reduction effects of the selected objects shapes were studied. The results are classified into three distinguishable patterns of diffusion. Two objects shapes and arrangements selected for use in the hydraulic model investigation indicated its capability to reduce flow velocity satisfactorily consistent with the flow pattern in the preliminary findings.

A STUDY OF PILE DRIVING EFFECTS ON NEARBY BUILDING

Piles are used to support many major structures such as buildings and bridges. It is known that pile driving activity creates vibrations in the ground and may affect nearby building and structure. However, the different pile size and shape as well as installation distances factors remain as interesting subjects for studies. The effect of hammer driven piles installation were studied using laboratory scale model. Three main effects were studied in which they are the response on top and bottom of a building, the vibration creates by three different distances of driven pile and the vibration produced by two different pile sizes. It can be concluded that the effect of vibrations are higher at the bottom of the building. The result also indicated that the nearest distance of piling activity produced higher vibration. However, it is interesting to note that the smaller pile creates larger vibrations.