111 research outputs found
Modeling of sound propagation in urban streets containing trees using Markovian technique
It is claimed that the trees may become a possible control method for noise in streets and hence contribute another step towards a sustainable environment. This paper examined the capability of an abatement scheme containing absorbent facades and trees in streets through a simulation model developed using the novel approach based upon Markovian techniques. The study showed that sound pressure level in a street containing trees relative to that in an empty street predicted by the Markov model was in good agreement with predictions obtained using commercial software, RAYNOISE model. Within the scope and assumptions in this study, it is shown streets containing trees and absorbent building façade result in sound reductions typically less than 1.5 dB. Hence trees in streets appear to have only a slight effect on sound attenuation, and thus make no significant contribution towards producing a sustainable environment in this respect
A Framework for Integrating Green Highway Performance Data with the Carbon Footprint Calculator in Malaysia
Highway concessionaires in Malaysia spend considerable assets in collecting, analysing and controlling different forms of data during highway projects’ life cycle. Considering this massive investment, nowadays the data use and information system reliability is becoming the key concern in terms of delivering value to consumers as opposed to the amount generated. The data generated is extensive and heterogeneous. This paper provides a new paradigm for integrating green highway performance data with carbon footprint data for green highway assessment. This framework is used to improve the active use of data in the generation of information and to assist comprehensively in decision-making at all levels of management. The network approach used in this study is the main component for interlinking data with knowledge and decisions, identifying the parameters of data integration for green highway assessment, determining the criteria data for integration, and assessing the overall performance of data usage. Real-time green highway data scenarios are used to demonstrate the applicability of this framework. A new monitoring performance measure called the MyGHI-Dashboard is proposed to control green highway assessment processes and evaluate the level of data usage, which will serve as a green highway performance scorecard. Through data-driven insights, this new paradigm can be used as a benchmarking model by highway authorities to make efficient and accurate decisions. This study is expected to become the central reference to mitigate the challenge associated with the use of highway performance data in real-time for Malaysian highway development
Earthquake resistance school building using Peninsular Malaysia bedrock response spectrum
Response spectrum is a very useful tool in earthquake engineering for estimating the performance of structures. In this research, attenuation equation will be used to find the response spectrum of bedrock to predict reliable and more accurate ground motions as far 700 km from potential earthquake sources. School building can be made to resist earthquake using the data of this response spectrum. According to historical records, the earthquakes that influenced Peninsular Malaysia are originated from two earthquake faults: the Sumatra subduction zone and Sumatra great fault zone. The worst earthquake ever occurred in Sumatra subduction zone is identified as Mw = 9.11 and Mw = 7.81 for Sumatra fault zone. These data were then used to predict the response spectrum of bedrock in Malaysia using Probabilistic Seismic Hazard Analysis (PSHA). The response spectrum data accumulated is then use to study on the performance of the school building during earthquake. Analysis of building shows that the values of moment for combination load 2 increases about 15.07 percents for column 1 and approximately 4.70 percents for beam 2. Based on the results, the resultant forces of school building during earthquake loadings are larger than without earthquake loading
The weightage of environmental elements for Malaysia state green road index of rural area
“Green road” is a concept introduced to meet the requirements of economic, societal, and environmental aspects in road construction and its operation. Towards the responsive efforts of sustainable development, many countries had established their environmentally friendly green road assessment tools including for highways and roads. However, the application of the tools is somehow limited to specific project life cycle such for design and planning assessment and/or only for the higher cluster of the road such as toll road or federal highway, but rarely focus on road in rural area. This paper therefore aims to identify the appropriate environmental criteria and elements as proposal for Malaysia State Road Index for the rural area. The weightage of environmental elements for the Malaysia State Road Index for the rural area was established in the discussion of this paper. The environmental criteria and elements were reviewed via critical literature review of content analysis were of ‘green tools’. The confirmation of weightage was conducted via questionnaires development and responded by the focus group discussion (FGD) and validation survey. The FGD were the experts involved in road infrastructure development. The data is analysed using the Statistical Package for the Social Sciences (SPSS) software. This study discovered ten sub-criteria and thirty-three elements under ‘green road’ of significant environmental sustainability elements. The result showcases a fair distribution of weightage for each element within their sub-criteria
Confirmatory Factor Analysis of the Life Cycle Costing Sub-Cost Distribution for Industrialised Building System using SEM-PLS
Industrialised Building System (IBS) contributes a great shift in sustainable construction, however previous studies have proven that one of the hindrances in promoting sustainable in IBS, is a high cost for pre-cast material components, thus effected the overall cost. In addition, the introduction of Life Cycle Costing (LCC) leads in providing a better and comprehensive cost estimation; as well as provides a significant advantage in the preparation of cost estimates, hence it provides a better baseline for decision making. The lacking application of LCC in IBS is still in trivial impact, where Malaysia experiences a slower progress of IBS construction, even though robust steps has been taken by the Government to influence construction players to accommodate LCC in projecting a comprehensive cost estimates, especially for IBS projects. This paper highlights an outcome of study that simulate the causal effect relationship between IBS Cost Factors and LCC Cost Distribution. A questionnaire survey was used to associate the IBS cost factors and LCC cost distribution and followed by Structural Equation Modelling (SEM) analysis which validate the relationships between the factors. The result of analysis was developed based on findings from 102 responded questionnaires which were distributed to Quantity Surveyors from various agencies. There were 5 LCC cost distribution factors used in this research and 43 IBS Cost Factors to get associated with. SEM-PLS was used to eliminate the cost association by eliminating factors recorded a loading value less than 0.70. From 43 IBS Cost Factors used earlier, only 15 cost factors were retain for further analysis and the development of a cost estimates using LCC approach. The outcome of this analysis is expected to guide the construction players to achieve more practical cost estimates and feasible alternatives for decision making in IBS construction, by focusing on the critical cost contributed to the overall cost of IBS project in Malaysia
The motivation factors in the provision of green criteria in green building development
Recently, green building has become globally vital especially in developed country such as United State, Europe, Australia, Hong Kong, Japan, Korea and Singapore.The Malaysian construction industry identified the necessity of green rating tool to improve building development in tropical climate. The Green Building Index (GBI) is Malaysia’s industry recognised green rating tool for buildings to promote sustainability in the built environment and raise awareness of these issues among relevant stakeholders such as developers, architects, and contractors.This paper highlights motivation factors versus common criteria of green building in the provision of green building
development.The assessment of commercial and residential properties under the GBI rating tool is based on six main criteria: energy efficiency, indoor environment quality, sustainable site planning and management, materials and resources, water efficiency and innovation.The data presented in this paper are mainly derived responses to a questionnaire that were completed by architects, engineers, urban planner, contractors and builders, developers and other consultants who is involved in green building development. For analysis, a statistical methods are used with
Average Index portray the results. Accordingly, organisational motivation, social motivation, environmental motivation and economic motivation influenced the provision of green criteria.This paper finding leads the developer in decision making for common provision of green criteria in green building development
Traditional formwork system sustainability performance: Experts' opinion
The traditional formwork system is one of the commonly used systems in concrete construction. It is considered as one of the least observed activities in term of sustainability performance. In this paper, the sustainability performance of the traditional formwork has been assessed by using a multi-criteria assessment tool to facilitate the decision on the sustainability performance measurement. A quantitative five Likert scale survey study using judgemental sampling is employed in this study. A sample of 93 of engineering construction experts, with different fields including contractors, developers, and consultants in the Malaysian context has made the body of the collected primary data. The results show variety in the distribution of the respondents' working experience. The sustainability performance is considered moderately sustainable by the experts with only given 40.24 % of the overall total score for the three sustainable categories namely environmental, social and economic. Despite the finding that shows that the economic pillar was rated as the most sustainable aspect in comparison to the environmental and social pillars the traditional formwork system sustainability still needs enhancement. Further incorporation of the social and environmental pillars into the concrete construction the sustainability performance of traditional formwork system could be improved
Strength characteristics of iron ore tailing concrete
Materials used in proportioning of concrete have significant impact on the properties of concrete produced. Iron ore tailings (IOTs) is a waste product generated from the production process of iron ore. In this study, IOTs is used as partial replacement for natural sand in the production of normal strength concrete. Samples of Iron ore tailings from two different mines in Kota Tinggi were collected. The Physical properties of natural sand and these Iron ore tailings were determined. The Energy Dispersive X-ray Spectroscopy (EDS) and the microscopic image of these materials were also studied. Normal strength concrete was designed based on water/cement ratio of 0.54 and cement content of 463Kg/m3 was used in preparing the fresh concrete. For each kind of Iron ore tailings concrete, four different types of concrete samples were produced. The percentage of Iron ore tailings as partial replacement for sand in the sample was varied from 10% to 40% at 10% interval. For each concrete sample, the average of three cubes, three cylinders and three prism specimen results was used for the determination of the compressive strength, splitting tensile strength and the flexural strength respectively. Also studied are the water absorption, the ultrasonic pulse velocity and the mode of failure of the IOTs concrete compared with the normal strength concrete. The concrete sample CZT30 containing 30% IOTs recorded the highest 28days compressive strength of 43.7 N/mm2
Higher learning institution challenges of decision making for green building development
Developing a green building requires precise and effective preliminary planning in which it is clearly caused by the challenges and uncertainty measures that are faced by the investors. The barriers have challenged the process of making decisions by the stakeholders to proceed for a green building development. This paper aims to determine the green building investment barriers that hinder the penetration of this development into the market in institutional campuses in Malaysia. The barriers of green building investment were identified through a questionnaire survey. Higher Learning Institution (HLI) is the scope of the study to green building investment barriers and the university key leaders are the respondents. A statistical analysis was employed with descriptive analysis and correlational analysis to determine the level of challenges corresponding to the criterias that influence in decision making for green building investment and to identify the relationship between those main barriers with the main corresponding crieteria such as government, finance, stakeholders, compliance, technical knowledge, tools and methods. It has been found that the challenges of technical barriers including stakeholders, compliance, knowledge and tools influence significantly decision making process of green building development in institutional campuses
Late payment practices in the malaysian construction industry
Factors that influence contractors „cash flow are the frequency of payment, delay , profit margin, retention fund, payment term to the supplier and subcontractor, advanced payment and others. L ate payment from the client has become a habit in the construction industry and this practice had cause d many implications such as bankruptcy, the higher contract sum due to higher risk, uncomfortable relationship between the payer and payee, disturbance of supply chain and others. The aim of this paper is to examine the late payment practices in the Malaysi an construction industry. Thirty seven (37) sets of questionnaire had been collected among the Grade G7 contractors and subcontractors in the state of Selangor based on convenience sampling . The collected data were analysed by using frequency distribution and relative important index (RII). The Data then was tabulated and illustrated in the form of charts. The results of the study show that the late payment is one of the most critical proble ms in the Malaysian construction industry. The majority of the contractor experienced late payment quite frequently and even beyon d the stipulated contract term. The top three impacts of the late payment problems are the negative chain effe ct on other part ies, delay in project completion and lead to bankruptcy or liquidation
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