Ali Hauashdh

Previous studies have reported that buildings consume nearly 36% of the total energy used and contribute towards 30% of the total carbon dioxide (CO2) emissions. Therefore, improving energy efficiency in buildings is essential to enhance a sustainable built environment. This research employed a case study approach with the Universiti Tun Hussein Onn Malaysia (UTHM) being selected as the case study. A number of buildings recorded high annual energy consumption (EC) data while others recorded low energy consumption. This was due to the absence of a benchmark line reference for campus buildings, thereby causing a significant difference in the energy consumption of each building. The study's aim was to develop an energy efficiency benchmark for university buildings by using statistical analysis. From statistical analysis, the standard practical range was between 72.5–141.0 kWh/m2/yr. Buildings with an energy consumption per unit area value below 72.5 kWh/m2/yr are regarded as best energy efficient buildings. In contrast, those above 141.0 kWh/m2/yr are considered poor energy efficient buildings. For recommendation, buildings that exceed the maximum value of this range require stricter supervision and monitoring by the university management.

Purpose: The largest share of a building maintenance budget goes towards preventing or repairing building defects. Also, building defects shorten a building’s lifetime, impact the user’s safety and health, prevent the buildings from performing their functions well and repairing building defects generates waste. Therefore, this study aims to specify the factors that affecting the number of building defects and how to reduce their negative impacts. Design/methodology/approach: A case study was used as a research strategy and convergent parallel mixed methods were used as research design. Quantitative and qualitative data were collected concurrently, followed by independent analyses of the quantitative and qualitative data, and then merged the two sets of results according to the procedure of using the convergent parallel design. Descriptive statistics analysed quantitative data, whilst qualitative data was analysed by the content analysis technique. Findings: The findings of this study explored the factors that affect the number of defects in buildings, the significant factors were related to the building’s life cycle in terms of design, construction, operation and maintenance phase; relevant attributes were construction teams, building users and maintenance teams. The study also addressed the approaches to minimise the negative impacts of those factors. Their negative impacts mainly contributed to increased building defects that increase maintenance costs, affect users’ safety and health, reduce buildings’ lifespan and cause environmental impact due to resource extraction. Originality/value: The existing studies have not adequately addressed the significant factors that affect the number of building defects. Also, emerging technologies and environmental sustainability considerations related to building defects have not been linked in previous related work. Therefore, the present study has contributed to filling this gap.

According to the National Energy Balance report released by the Energy Commission of Malaysia in 2016, the residential sector uses 21.6% of the total energy in Malaysia. Residents waste energy through inefficient energy consumption and a lack of awareness. Building occupants are considered the main factor that influences energy consumption in buildings, and to change energy consumption on an overall scale, it is crucial to change individual behaviour. Therefore, this study focused on analysing the energy consumption pattern and the behaviour of consumers towards energy consumption in their homes in the residential area of Batu Pahat, Johor. A self-administrated questionnaire approach was employed in this study. The findings of this study showed that the excessive use of air conditioners was a significant factor in the increasing electricity bills of homeowners as well as the inefficient use of electrical appliances. Also, this study determined the effect of awareness on consumer behaviour. This study recommends ways to help minimise energy consumption in the residential area.

Purpose: In recent years, there have been many concerns about issues surrounding building maintenance, which are continually increasing. However, there is a lack of comprehensive studies on building maintenance issues, their effects and the way forward. Therefore, the purpose of this paper is to carry out a comprehensive review of building maintenance issues, their effects and the way forward. It also aims to develop a conceptual model that can support future research.Design/methodology/approach: A systematic review of the literature published from 2009 to 2019 was carried out. Five relevant databases were searched, based on this study's search terms, and a narrative synthesis of the results from the included studies was carried out. Studies were eligible for inclusion if they fulfilled the inclusion criteria of this systematic review.Findings: This study has identified and classified building maintenance issues, their effects and the way forward, and also developed a conceptual model that demonstrates the association between issues, their effects and the way forward. The way forward of the conceptual model focuses on effective management, technical capability, development of human resources and cost optimisation.Originality/value: This paper addresses an important topic: the aspect in which it differs from existing studies is that, in the latter, the researchers studied a single sub-issue, whereas this systematic review includes a comprehensive study of building maintenance issues. Furthermore, this review has demonstrated how the way forward can moderate issues and their effects.

Peat soil is very compressible, which leads to an excessive settlement. Stabilization of peat soil is the way to improve the engineering properties of peat soil through mixing peat with supplementary cementation materials. Therefore, this study aims to investigate the stabilization of peat soil using fly ash, bottom ash and ordinary Portland cement (OPC) to improve the engineering properties of peat soil. Also to examine the possibility of fly ash and bottom ash waste reduction through using them as a binder of the mixture in soil improvement application. In this study, fly ash and bottom ash were collected from generation wastes at coal- fired electric power and stabilization of peat soil was done by mixing peat soil with fly ash, bottom ash and OPC. Unconfined compressive strength (UCS) and Fourier transform scanning electron microscope (FESEM) was conducted before and after the stabilization of peat soil. Also, some essential physicochemical properties of a mixture have identified before the mixing process. The findings of the compressive strength of peat soil were equal to 5 kPa at its natural state and after stabilization strength of peat soil was equal to 47 kPa. FESEM micrographs have shown ultrastructure of peat stabilization appears as inherent and coherent while the ultrastructure of original peat appears as incoherent and sporadic. The findings have revealed the effectiveness of fly ash and bottom ash to improve the strength of peat and the applicability of the utilization of coal ash waste as binder materials.

The frequency of floods increases annually in many countries of the world due to climate change. Flood is typically coupled to flowing water moving faster than normal. Thus, understanding the drag force behaviour due to the flowing water on concrete blocks is essential to predict floods risks since the concrete is the predominant material used in the construction of buildings, bridges, dams, canals and other infrastructure over the world. Nonetheless, previous studies were mostly focused on the resistance of concrete structure due to the load force, and there is a lack of studies about the resistance of concrete structure due to the drag force of flowing water. Therefore, this study aims to estimate the drag force of flowing water, which causes the displacement of concrete blocks. Also, to investigate the effects of concrete mass and flow velocity on the drag force. Three concrete cubes were used with dimensions 0.15 m 0.15 m 0.15 m and weighing between 6.486 kg to 7.847 kg. The concrete cube is installed in the middle of the open channel 10-m long, 0.3 m wide and 0.46 m depth Armfield S6 MKII flume. In this study, the flowing water exerts force on the cube concrete block in the direction of flow, known as the drag force. It was observed the mass of the block is an essential factor that affects the drag force on a concrete cube due to the flowing water. Therefore, each cube of concrete block with area 0.02235 (m2) and mass between 6.486 kg to 7.874 kg to be displaced was needed a drag force of flowing water between 2.737 N to 3.732 N. Also, it has been found that the drag force increases with the increasing the flow velocity.

Peat soil is very compressible where this characteristic is lead to an excessive settlement. Solidification of peat soil is a method to improve engineering properties of peat soil. Currently, solidification of peat soil is increasing, wherefore it is a critical need to study the environmental effects from solidified peat soil leachate due to solidification peat mixtures usually used materials of generation wastes from coal-fired electric power. The effect of leachate from solidified peat to the environment is one of the most important criteria that should be investigated. This study aims to investigate the environmental impacts of leachate from solidified peat affected by rainwater. In this study, solidification of hemic peat soil was done by mixing hemic peat soil with ordinary Portland cement (OPC), fly ash (FA) and bottom ash (BA). Leachate is the liquid that has percolated through a soil column outlets. Therefore, this study was to analysis the leachate from solidified hemic peat when it is saturated by rainwater in two different conditions, which are a dry and wet season by using physical model (soil column). The leachate samples were analyzed by using Ionic Chromatography (IC) and Inductively Coupled Plasma Mass Spectrometry (IC-MS). The anions concentration of leachate from solidified peat has increased for Cl-SO42-in wet condition as result rainwater inflow was increased during the wet condition, and the chemical composition of rainwater contains Cl-and SO42-. The concentration of cations on the leachate from solidified peat has increased at Fe+2 and Al+3 in wet condition, which proven solidified peat has an effect on the leachate In comparison with leachate of non-solidified peat. The concentration of anions for Cl-and SO42-the leachate still consider in the normal range of groundwater concentration that classified as freshwater, but in case FA, BA, and OPC are used excessively in the mixture for solidifying peat in a wetland, leachate from solidified peat will effect on elements concentration of groundwater and land properties.