57 research outputs found
Structural modelling of cause and effect factors of construction waste generation in Malaysian Construction Industry
Construction industry contributes significantly in improving socio-economic
development of a country. However, this industry faces serious problems of
construction waste generated worldwide including Malaysia. Construction waste is
results from various factors which are necessary to identify for reducing the waste
generated in construction project. Hence, this study focused on developing a
structural model of construction waste generation and determining the most
important group that contributes to construction waste generation. The questionnaire
consisted of 77 causative factors which then clustered into 7 groups and 13 effects
factors of construction waste which are clustered into 3 groups. These factors and
assigned groups were validated by 30 construction personnel (contractors,
consultants and clients) during the pilot study. The actual survey was conducted with
a total of 302 questionnaires were received by respond rate of 60%. The data analysis
is carried out using SmartPLS software. A structural model of construction waste
generation was developed based on 7 groups of causative factors and 3 groups of
effect factors using Partial Least Squared-Structural Equation Modelling (PLS-SEM)
technique. It was found that the model is fit due to the R² value of 0.451 (R2 ≥ 0.26 =
substantial). The model identifies that all 10 groups are significant with t-value ≥
2.58 from bootstrapping process of 5000 random samples. The model indicates that
Handling of Materials and Equipment group has the highest impact on construction
waste generation. Finally, this finding was validated by 22 construction practitioners
who agreed that Handling of Material and Equipment group of factors contributes the
highest amount of construction waste generation at site. This group of factors should
be avoided during construction works to reduce the waste generation. The findings of
this study are contributed to understand clearly the cause and effect factors of
construction waste generation in Malaysia
An investigation on benefits and future expectation of Industrialised Building System (IBS) implementation in construction practices
Industrialised Building System (IBS) is well known in many developing countries due to the benefits that can be derived from its applications in construction projects. However, the low percentage of IBS usage may be due to lack of awareness and knowledge about IBS among many professionals. There may be factors that contribute to a lack of interest from the client towards IBS. The aim of this study is to improve the application of IBS particularly in private construction projects in Malaysia by determining the benefits and expectation on application of IBS in private construction projects. This study adopts a quantitative method using questionnaires that were sent to 35 construction firms as a sampling frame. Finally, the finding of this study hopefully could assist professional parties in construction industry in providing a better ground knowledge for improving decisions making to achieve the success of IBS construction projects implementation and also this study will achieved the project objectives in terms of predetermined objectives that are mostly within the time, specified budget and standard qualit
Resource allocation in coordinated multipoint long term evolution-advanced networks
Coordinated Multipoint (CoMP) in Long Term Evolution-Advanced (LTE- Advanced) improves the cell-edge data rates and the network spectral efficiency
through base station coordination. In order to achieve high quality of service (QoS)
in CoMP network, resource allocation approach is one of the main challenges. The
resource allocation strategies of cells in CoMP network affect each other’s
performance. Thus, the resource allocation approach should consider various
diversities offered in multiuser wireless networks, particularly in frequency, spatial
and time dimensions. The primary objective of this research is to develop resource
allocation strategy for CoMP network that can provide high QoS. The resource
allocation algorithm is developed through three phases, namely Low-Complexity
Resource Allocation (LRA), Optimized Resource Allocation (ORA) and Cross-Layer
Design of ORA (CLD-ORA). The LRA algorithm is a three-step resource allocation
scheme that consists of user selection module, subcarrier allocation module and
power allocation module which are performed sequentially in a multi-antenna CoMP
network. The proposed ORA algorithm enhances throughput in LRA while ensuring
fairness. ORA is formulated based on Lagrangian method and optimized using
Particle Swarm Optimization (PSO). The design of CLD-ORA algorithm is an
enhancement of the ORA algorithm with resource block (RB) scheduling scheme at
medium access control (MAC) layer. Simulation study shows that the ORA
algorithm improves the network sum-rate and fairness index up to 70% and 25%, respectively and reduces the average transmit power by 41% in relative to LRA
algorithm. The CLD-ORA algorithm has further enhanced the LRA and ORA
algorithms with network sum-rate improvement of 77% and 33%, respectively. The
proposed resource allocation algorithm has been proven to provide a significant
improved performance for CoMP LTE-Advanced network and can be extended to
future 5G network
Identification of Delay Factors from Mecca's Construction Experts Perspective
Delay in construction project is a common phenomenon in construction industry project where there are numerous studies on this issue that identified the factors causing the delay. This paper presents a study on identifying significant delay factors encountered by construction practitioners in Mecca city. A total of 81 delay factors were identified from seven research articles on construction delay study conducted in several parts of Saudi Arabia. These factors were included in the questionnaire form where this questionnaire was distributed amongst the construction experts who involved in the current construction projects in Mecca. The survey was carried out by interviewing 28 selected experts, who are from consultant, contractors and project management’s parties. The collected data were analyzed by using Average Index method for each factor and these factors were ranked based on the index to determine its significance to the delay. The result found that the most six significant factors are Changes in design documents, Low productivity level of labour, Shortage of manpower, Difficulties in financing project by contractor, Poor contract management, and Unqualified workforce. The results of this research are helpful to the construction community in avoiding any potential delay for their future construction projects in order to achieve successful construction projects
Mitigation measures for significant factors instigating cost overrun in highway projects
Construction industry has created numerous employment opportunities and playing a role model in economic growth of Pakistan. This industry is facing serious and critical problem of cost overrun especially in highway sector in country Pakistan particularly in Sindh Province. The purpose of this study is to identify mitigation measures for significant factors of cost overrun in highway projects of Sindh Province. In this study, mixed-mode research approach has been used. Quantitatively, a structured questionnaire based on 64 common factors of cost overrun from in-depth literature review was developed and distributed to30 selected respondents among the client, contractor and consultant having more than 15 years of experience in handling highway projects in Sindh Province. The collected data was statistically analyzed using SPSS where 8 most significant factors of cost overrun were identified. Qualitatively, the identified eight most significant factors were then incorporated in open ended questionnaire and distributed to 30 selected experts for them to write possible mitigation measures for each of the significant factors. The data was then analyzed through content analysis technique to rank the mitigation measures according to their substantiality. The results of this study would be helpful for construction practitioners to be used as reference in taking up appropriate measures in controlling cost overrun in highways projects in Pakista
Assessing Delay Factors and Mitigation Measures in Building Maintenance Works
When it comes to the operation of a construction industry, building maintenance is critical. Any structure must be well-maintained to prevent minor problems from becoming major ones. Delayed building maintenance may result in increased repair costs as well as a reduction in building lifespan. To avoid this problem, research has been conducted to identify the factors that cause building maintenance delays and mitigation measures to resolve building maintenance delays. To achieve the study's objectives, extensive literature research and a questionnaire survey were conducted. Based on previous literature research, accumulated data was used to create a questionnaire for 250 Malaysian building maintenance delay factors and mitigation measures. A group of professionals and experts, including top management, project managers, engineers, architects, assistant engineers, technicians, human resources and administration, and others, participated in this survey. SPSS statistical software was used to analyse the collected data using the average mean index method and correlation. According to the data, the three highest mean index values from the factors that cause maintenance work delays are an increase in maintenance costs as the building age increases, an incorrect timing for work can incur higher maintenance costs when a critical job item is overlooked, and improper planning and budgeting. For correlation analysis, it was found that the correlations amongst the five groups of delay factors are having strong relationship with Pearson correlation value of 0.5. While for mitigation measures of the delay, it was found that three highest ranks are prefer other organizational structure follows by policy and objective and good communication. The findings can assist construction practitioners in prioritising their maintenance works
Certain Building Materials with Respect to Their Thermal Properties as Well as to Their Impact to Environment
Thermal properties of certain building materials were studied with respect to environmental aspects. The building materials with significant insulation properties were laboratory tested using the special equipment based on Peltier module. During the experimental work, the samples of the following materials were tested: Expanded polystyrene (EPS), Autoclaved aerated concrete (AAC): Ytong, Calcium Silicate Board: Super-Isol and Foam glass (Cellular Glass Insulation): PERINSUL. The temperature was measured directly in connection of material with the Peltier module as well as in the distances of 5mm, 27.5mm, 50mm and 95mm from the Peltier module. The temperature taken at the surface of Peltier module reached -22°C, a typical temperature in the cold winter season. The results of the laboratory experimental work were modelled using the graphic representation. Modelling the thermal distribution will help to determine the ideal material thickness in the design of the building insulation.Â
Study of Site's Construction Waste in Batu Pahat, Johor
AbstractRapid growth in construction industry has increased the problems of construction waste around the world. In Malaysia, the construction industry plays a significant role both in the infrastructure development and economic sectors. The construction industry is been regarded as one of the major contributors of negative impact to the environment. To reduce these negative impacts, it needs a comprehensive understanding of the construction waste generation and management. Hence, the objective of this research are to identify the construction waste generation on site, to quantify the physical wastes that are generated at the construction site and to determine the construction waste management plan that have been applied in project. This research involves two ways of data collection which are by interviews and site observation. This study was conducted at three site's projects around Batu Pahat, Johor. The data collection were taken weekly in two month duration. The finding shows that, there were six types of waste produce on the three sites which are timber, metal, concrete, mortar, packaging waste and bricks. Throughout the quantifying data of the construction wastes, it shows that timber wastes were the largest contributor to the construction wastes which then followed by bricks, packaging waste and concrete. Study on construction Waste Management Plan (WMP) at sites had showed that, they were not fully applied of WMP. Hence, to minimize the waste, WMP should be fully applied on site. The finding will be an input to authorities in shaping better policy of construction waste management
Investigating the effect of poor communication in terms of cost and time overruns in the construction industry
Cost and time overruns are major issues faced by the construction industry worldwide. Studies have shown that various factors cause these overruns. One of the critical factors that cause these overruns is poor communication.This study aims to study and measure the severity of poor communication in causing cost and time overruns in construction projects. The study adopted two consecutive approaches to study the effect of poor communication in causingcost and time overruns. The first approach was to conduct an extensive literature review to extract causative factors from diverse construction industries that consider poor communication as a causative factor,then to determineits severity percentage,among other factors for each study. From the analysis, it can be concluded that developed countries that apply information communication technology and advanced communication systems have lowerseverity percentages compared to other countries. The second approach was to conduct a qualitative study by interviewing construction experts and to examine their commentsand criticisms ofthe results obtained from the literature. Experts were asked to highlight their views on the severity of poor communication in the construction industry. The outcome of these interviews was thematically analysed. The findings show that poor communication has a significanteffect on cost and time overruns in construction projects
Assessment of Delay Factors in Saudi Arabia Railway/Metro Construction Projects
Railway construction industry has devoted vast amount of resources into advancing the management and technology of railway construction, yet most project in this industry often failed to comply with the set deadlines and budget limits. This study was conducted to recognize the critical factors that are causing delays in the construction of Riyadh Metro project, Saudi Arabia. From a thorough literature review, thirty-six (36) factors causing delays were identified which were then distributed to qualified industry experts in a survey questionnaire. A total of 105 respondents were gathered during the data collection. The data was then evaluated statistically by utilizing different calculation tools that are frequency adjusted importance index for the delay factor ranking, and Spearman's correlation coefficient for the link between two different set of data. The result of this research identified the top five main delay factors to the railway construction projects which are “Client's decision-making process and changes in control proceduresâ€, “Design Errors (including ambiguities and discrepancies of details/specifications)â€, “Labor skills levelâ€, “Design changes by Client or Consultant†and lastly, “Issues regarding permissions/ approvals from other stakeholdersâ€. Finally, this study is hoped to help the railway construction industry in bettering itself by highlighting which issues should be focused on to counter the delays and reduce downtimes
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