Search results for: construction mechanism
6633 Identifying Reforms Required in Construction Contracts from Resolved Disputed Cases
Authors: K. C. Iyer, Yogita Manan Bindal, Sumit Kumar Bakshi
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The construction industry is plagued with disputes and litigation in India with many stalled projects seeking dispute resolution. This has an adverse effect on the performance and overall project delivery and impacts future investments within the industry. While construction industry is the major driver of growth, there has not been major reforms in the government construction contracts. The study is aimed at identifying the proactive means of dispute avoidance, focusing on reforms required within the construction contracts, by studying 49 arbitration awards of construction disputes. The claims presented in the awards are aggregated to study the causes linked to the contract document and are referred against the prospective recommendation and practices as surveyed from literature review of research papers. Within contract administration, record keeping has been a major concern as they are required by the parties to substantiate the claims or the counterclaims and therefore are essential in any dispute redressal process. The study also observes that the right judgment is inhibited when the record keeping is improper and due to lack of coherence between documents, the dispute resolution period is also prolonged. The finding of the research will be relevant to industry practitioners in contract drafting with a view to avoid disputes.Keywords: construction contract, contract administration, contract management, dispute avoidance
Procedia PDF Downloads 2666632 Reflection on the Resilience Construction of Megacities Under the Background of Territorial Space Governance
Authors: Xin Jie Li
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Due to population agglomeration, huge scale, and complex activities, megacities have become risk centers. To resist the risks brought by development uncertainty, the construction of resilient cities has become a common strategic choice for megacities. As a key link in promoting the modernization of the national governance system and governance capacity, optimizing the layout of national land space that focuses on ecology, production, and life and improving the rationality of spatial resource allocation are conducive to fundamentally promoting the resilience construction of megacities. Therefore, based on the perspective of territorial space governance, this article explores the potential risks faced by the territorial space of megacities and proposes possible paths for the resilience construction of megacities from four aspects: promoting the construction of a resilience system throughout the entire life cycle, constructing a disaster prevention and control system with ecological resilience, creating an industrial spatial pattern with production resilience, and enhancing community resilience to anchor the front line of risk response in megacities.Keywords: mega cities, potential risks, resilient city construction, territorial and spatial governance
Procedia PDF Downloads 586631 4-DOFs Parallel Mechanism for Minimally Invasive Robotic Surgery
Authors: Khalil Ibrahim, Ahmed Ramadan, Mohamed Fanni, Yo Kobayashi, Ahmed Abo-Ismail, Masakatus G. Fujie
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This paper deals with the design process and the dynamic control simulation of a new type of 4-DOFs parallel mechanism that can be used as an endoscopic surgical manipulator. The proposed mechanism, 2-PUU_2-PUS, is designed based on the screw theory and the parallel virtual chain type synthesis method. Based on the structure analysis of the 4-DOF parallel mechanism, the inverse position equation is studied using the inverse analysis theory of kinematics. The design and the stress analysis of the mechanism are investigated using SolidWorks software. The virtual prototype of the parallel mechanism is constructed, and the dynamic simulation is performed using ADAMS TM software. The system model utilizing PID and PI controllers has been built using MATLAB software. A more realistic simulation in accordance with a given bending angle and point to point control is implemented by the use of both ADAMS/MATLAB software. The simulation results showed that this control method has solved the coordinate control for the 4-DOF parallel manipulator so that each output is feedback to the four driving rods. From the results, the tracking performance is achieved. Other control techniques, such as intelligent ones, are recommended to improve the tracking performance and reduce the numerical truncation error.Keywords: parallel mechanisms, medical robotics, tracjectory control, virtual chain type synthesis method
Procedia PDF Downloads 4696630 Permissible Horizontal Displacements during the Construction of Vertical Shafts in Soft Soils at the Valley of Mexico: Case History
Authors: Joel M. De La Rosa R.
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In this paper, the results obtained when monitoring the horizontal deformations of the soil mass are detailed, during each of the construction stages of several vertical shafts located in the soft soils of the Valley of Mexico, by means of the flotation method. From the analysis of these results, the magnitude and percentage relationship with respect to the diameter and depth of excavation of the horizontal deformations that occurred during the monitoring period is established. Based on the horizontal deformation monitoring system and the information provided by the supervisor's site log, the construction stages that have the greatest impact on deformations are established. Additionally, an analysis of the deformations is carried out, which takes into account the resistance and deformability characteristics of the excavated soils, as well as the prevailing hydraulic conditions. This work will allow construction engineers and institutions in charge of infrastructure works in the Valley of Mexico to establish permissible ranges for horizontal deformations that can occur in very soft and saturated soils, during the different construction stages; improving response protocols to potentially dangerous behaviors.Keywords: vertical shaft, flotation method, very soft clays, construction supervision
Procedia PDF Downloads 1896629 Impact of Safety and Quality Considerations of Housing Clients on the Construction Firms’ Intention to Adopt Quality Function Deployment: A Case of Construction Sector
Authors: Saif Ul Haq
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The current study intends to examine the safety and quality considerations of clients of housing projects and their impact on the adoption of Quality Function Deployment (QFD) by the construction firm. Mixed method research technique has been used to collect and analyze the data wherein a survey was conducted to collect the data from 220 clients of housing projects in Saudi Arabia. Then, the telephonic and Skype interviews were conducted to collect data of 15 professionals working in the top ten real estate companies of Saudi Arabia. Data were analyzed by using partial least square (PLS) and thematic analysis techniques. Findings reveal that today’s customer prioritizes the safety and quality requirements of their houses and as a result, construction firms adopt QFD to address the needs of customers. The findings are of great importance for the clients of housing projects as well as for the construction firms as they could apply QFD in housing projects to address the safety and quality concerns of their clients.Keywords: construction industry, quality considerations, quality function deployment, safety considerations
Procedia PDF Downloads 1256628 Optimizing Recycling and Reuse Strategies for Circular Construction Materials with Life Cycle Assessment
Authors: Zhongnan Ye, Xiaoyi Liu, Shu-Chien Hsu
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Rapid urbanization has led to a significant increase in construction and demolition waste (C&D waste), underscoring the need for sustainable waste management strategies in the construction industry. Aiming to enhance the sustainability of urban construction practices, this study develops an optimization model to effectively suggest the optimal recycling and reuse strategies for C&D waste, including concrete and steel. By employing Life Cycle Assessment (LCA), the model evaluates the environmental impacts of adopted construction materials throughout their lifecycle. The model optimizes the quantity of materials to recycle or reuse, the selection of specific recycling and reuse processes, and logistics decisions related to the transportation and storage of recycled materials with the objective of minimizing the overall environmental impact, quantified in terms of carbon emissions, energy consumption, and associated costs, while adhering to a range of constraints. These constraints include capacity limitations, quality standards for recycled materials, compliance with environmental regulations, budgetary limits, and temporal considerations such as project deadlines and material availability. The strategies are expected to be both cost-effective and environmentally beneficial, promoting a circular economy within the construction sector, aligning with global sustainability goals, and providing a scalable framework for managing construction waste in densely populated urban environments. The model is helpful in reducing the carbon footprint of construction projects, conserving valuable resources, and supporting the industry’s transition towards a more sustainable future.Keywords: circular construction, construction and demolition waste, material recycling, optimization modeling
Procedia PDF Downloads 576627 Basic Research on Applying Temporary Work Engineering at the Design Phase
Authors: Jin Woong Lee, Kyuman Cho, Taehoon Kim
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The application of constructability is increasingly required not only in the construction phase but also in the whole project stage. In particular, the proper application of construction experience and knowledge during the design phase enables the minimization of inefficiencies such as design changes and improvements in constructability during the construction phase. In order to apply knowledge effectively, engineering technology efforts should be implemented with design progress. Among many engineering technologies, engineering for temporary works, including facilities, equipment, and other related construction methods, is important to improve constructability. Therefore, as basic research, this study investigates the applicability of temporary work engineering during the design phase in the building construction industry. As a result, application of temporary work engineering has a greater impact on construction cost reduction and constructability improvement. In contrast to the existing design-bid-build method, the turn-key and CM (construct management) procurement methods currently being implemented in Korea are expected to have a significant impact on the direction of temporary work engineering. To introduce temporary work engineering, expert/professional organization training is first required, and a lack of client awareness should be preferentially improved. The results of this study are expected to be useful as reference material for the development of more effective temporary work engineering tasks and work processes in the future.Keywords: Temporary Work Engineering, Design Phase, Constructability, Building Construction
Procedia PDF Downloads 3886626 Critical Path Segments Method for Scheduling Technique
Authors: Sherif M. Hafez, Remon F. Aziz, May S. A. Elalim
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Project managers today rely on scheduling tools based on the Critical Path Method (CPM) to determine the overall project duration and the activities’ float times which lead to greater efficiency in planning and control of projects. CPM was useful for scheduling construction projects, but researchers had highlighted a number of serious drawbacks that limit its use as a decision support tool and lacks the ability to clearly record and represent detailed information. This paper discusses the drawbacks of CPM as a scheduling technique and presents a modified critical path method (CPM) model which is called critical path segments (CPS). The CPS scheduling mechanism addresses the problems of CPM in three ways: decomposing the activity duration of separated but connected time segments; all relationships among activities are converted into finish–to–start relationship; and analysis and calculations are made with forward path. Sample cases are included to illustrate the shortages in CPM, CPS full analysis and calculations are explained in details, and how schedules can be handled better with the CPS technique.Keywords: construction management, scheduling, critical path method, critical path segments, forward pass, float, project control
Procedia PDF Downloads 3536625 Optimizing Recycling and Reuse Strategies for Circular Construction Materials with Life Cycle Assessment
Authors: Zhongnan Ye, Xiaoyi Liu, Shu-Chien Hsu
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Rapid urbanization has led to a significant increase in construction and demolition waste (C&D waste), underscoring the need for sustainable waste management strategies in the construction industry. Aiming to enhance the sustainability of urban construction practices, this study develops an optimization model to effectively suggest the optimal recycling and reuse strategies for C&D waste, including concrete and steel. By employing Life Cycle Assessment (LCA), the model evaluates the environmental impacts of adopted construction materials throughout their lifecycle. The model optimizes the quantity of materials to recycle or reuse, the selection of specific recycling and reuse processes, and logistics decisions related to the transportation and storage of recycled materials with the objective of minimizing the overall environmental impact, quantified in terms of carbon emissions, energy consumption, and associated costs, while adhering to a range of constraints. These constraints include capacity limitations, quality standards for recycled materials, compliance with environmental regulations, budgetary limits, and temporal considerations such as project deadlines and material availability. The strategies are expected to be both cost-effective and environmentally beneficial, promoting a circular economy within the construction sector, aligning with global sustainability goals, and providing a scalable framework for managing construction waste in densely populated urban environments. The model is helpful in reducing the carbon footprint of construction projects, conserving valuable resources, and supporting the industry’s transition towards a more sustainable future.Keywords: circular construction, construction and demolition waste, life cycle assessment, material recycling
Procedia PDF Downloads 826624 Factors Influencing the Use of Green Building Practices in the South African Residential Apartment Construction
Authors: Mongezi Nene, Emma Ayesu-Koranteng, Christopher Amoah, Ayo Adeniran
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Although its use has been criticized over the years as being unencouraging, the green building concept is quickly overtaking other concepts, particularly in the construction of commercial properties. The goal of the study is to identify the variables influencing the use of green building practices when developing residential structures. A qualitative methodology, using interviews with semi-structured open-ended questions to 35 property practitioners operating residential apartments in Bloemfontein, South Africa, was used to collect primary data which was analysed using thematic content analysis. The findings show that while respondents have a good understanding of green building principles, they are not being used in the construction of residential buildings in South Africa due to issues with green building approval procedures, the potential for tenant rent increases, the cost of materials, technical issues, contractual issues, and a lack of awareness, among others. This paper recommends among others an urgent need to implement measures by stakeholders towards enhancing the adoption of green building concepts in the construction of residential buildings as well as incentivising its construction through lowered property rates.Keywords: green building, residential apartments, construction, South Africa
Procedia PDF Downloads 1056623 Integration of LCA and BIM for Sustainable Construction
Authors: Laura Álvarez Antón, Joaquín Díaz
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The construction industry is turning towards sustainability. It is a well-known fact that sustainability is based on a balance between environmental, social and economic aspects. In order to achieve sustainability efficiently, these three criteria should be taken into account in the initial project phases, since that is when a project can be influenced most effectively. Thus the aim must be to integrate important tools like BIM and LCA at an early stage in order to make full use of their potential. With the synergies resulting from the integration of BIM and LCA, a wider approach to sustainability becomes possible, covering the three pillars of sustainability.Keywords: building information modeling (BIM), construction industry, design phase, life cycle assessment (LCA), sustainability
Procedia PDF Downloads 4516622 Risk Factors Affecting Construction Project Cost in Oman
Authors: Omar Amoudi, Latifa Al Brashdi
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Construction projects are always subject to risks and uncertainties due to its unique and dynamic nature, outdoor work environment, the wide range of skills employed, various parties involved in addition to situation of construction business environment at large. Altogether, these risks and uncertainties affect projects objectives and lead to cost overruns, delay, and poor quality. Construction projects in Oman often experience cost overruns and delay. Managing these risks and reducing their impacts on construction cost requires firstly identifying these risks, and then analyzing their severity on project cost to obtain deep understanding about these risks. This in turn will assist construction managers in managing and tacking these risks. This paper aims to investigate the main risk factors that affect construction projects cost in the Sultanate of Oman. In order to achieve the main aim, literature review was carried out to identify the main risk factors affecting construction cost. Thirty-three risk factors were identified from the literature. Then, a questionnaire survey was designed and distributed among construction professionals (i.e., client, contractor and consultant) to obtain their opinion toward the probability of occurrence for each risk factor and its possible impact on construction project cost. The collected data was analyzed based on qualitative aspects and in several ways. The severity of each risk factor was obtained by multiplying the probability occurrence of a risk factor with its impact. The findings of this study reveal that the most significant risk factors that have high severity impact on construction project cost are: Change of Oil Price, Delay of Materials and Equipment Delivery, Changes in Laws and Regulations, Improper Budgeting, and Contingencies, Lack of Skilled Workforce and Personnel, Delays Caused by Contractor, Delays of Owner Payments, Delays Caused by Client, and Funding Risk. The results can be used as a basis for construction managers to make informed decisions and produce risk response procedures and strategies to tackle these risks and reduce their negative impacts on construction project cost.Keywords: construction cost, construction projects, Oman, risk factors, risk management
Procedia PDF Downloads 3466621 In silico Model of Transamination Reaction Mechanism
Authors: Sang-Woo Han, Jong-Shik Shin
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w-Transaminase (w-TA) is broadly used for synthesizing chiral amines with a high enantiopurity. However, the reaction mechanism of w-TA has been not well studied, contrary to a-transaminase (a-TA) such as AspTA. Here, we propose in silico model on the reaction mechanism of w-TA. Based on the modeling results which showed large free energy gaps between external aldimine and quinonoid on deamination (or ketimine and quinonoid on amination), withdrawal of Ca-H seemed as a critical step which determines the reaction rate on both amination and deamination reactions, which is consistent with previous researches. Hyperconjugation was also observed in both external aldimine and ketimine which weakens Ca-H bond to elevate Ca-H abstraction.Keywords: computational modeling, reaction intermediates, w-transaminase, in silico model
Procedia PDF Downloads 5476620 Strength Analysis of RCC Dams Subject to the Layer-by-Layer Construction Method
Authors: Archil Motsonelidze, Vitaly Dvalishvili
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Existing roller compacted concrete (RCC) dams indicate that the layer-by-layer construction method gives considerable economies as compared with the conventional methods. RCC dams have also gained acceptance in the regions of high seismic activity. Earthquake resistance analysis of RCC gravity dams based on nonlinear finite element technique is presented. An elastic-plastic approach is used to describe the material of a dam while it is under static conditions (period of construction). Seismic force, as an acceleration equivalent to that produced by a real earthquake, is supposed to act when the dam is completed. The materials of the dam and foundation may be nonhomogeneous and anisotropic. The “dam-foundation” system is idealized as a plain strain problem.Keywords: finite element method, layer-by-layer construction, RCC dams, strength analysis
Procedia PDF Downloads 5496619 The Impact of Using Building Information Modeling Technology in Construction Projects Management
Authors: Mohammad Ashraf
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This research links the use of Building Information Modeling technology in constructions and infrastructure projects, starting from the moment when considering the establishment of a project to demolishing or renovating it, going through the design work, planning, procurement and implementation. BIM Software's which used are Revit, Navisworks and Asta Project in the case study for the Atletico Madrid Stadium project (Wanda Stadium). Also, the project improves through various phases of construction (planning - implementation - management). Besides, the level of the details managed within this project advances gradually. In addition, the construction process problems become about 30 % less than before, resulting from high coordination between designing, implementation and follow through that is done by the project management office (PMO). The current disposition in the industry is to tightly manage the detail contained within the planning and coordination phases of construction, but we miss the opportunity to manage that data as it matures and grows into the execution and commissioning phases.Keywords: construction management, BIM technology, planning, design, procurements, critical path method
Procedia PDF Downloads 2806618 Young’s Modulus Variability: Influence on Masonry Vault Behavior
Authors: Abdelmounaim Zanaz, Sylvie Yotte, Fazia Fouchal, Alaa Chateauneuf
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This paper presents a methodology for probabilistic assessment of bearing capacity and prediction of failure mechanism of masonry vaults at the ultimate state with consideration of the natural variability of Young’s modulus of stones. First, the computation model is explained. The failure mode is the most reported mode, i.e. the four-hinge mechanism. Based on this assumption, the study of a vault composed of 16 segments is presented. The Young’s modulus of the segments is considered as random variable defined by a mean value and a coefficient of variation CV. A relationship linking the vault bearing capacity to the modulus variation of voussoirs is proposed. The failure mechanisms, in addition to that observed in the deterministic case, are identified for each CV value as well as their probability of occurrence. The results show that the mechanism observed in the deterministic case has decreasing probability of occurrence in terms of CV, while the number of other mechanisms and their probability of occurrence increase with the coefficient of variation of Young’s modulus. This means that if a significant change in the Young modulus of the segments is proven, taken it into account in computations becomes mandatory, both for determining the vault bearing capacity and for predicting its failure mechanism.Keywords: masonry, mechanism, probability, variability, vault
Procedia PDF Downloads 4436617 Establishing a Sustainable Construction Industry: Review of Barriers That Inhibit Adoption of Lean Construction in Lesotho
Authors: Tsepiso Mofolo, Luna Bergh
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The Lesotho construction industry fails to embrace environmental practices, which has then lead to excessive consumption of resources, land degradation, air and water pollution, loss of habitats, and high energy usage. The industry is highly inefficient, and this undermines its capability to yield the optimum contribution to social, economic and environmental developments. Sustainable construction is, therefore, imperative to ensure the cultivation of benefits from all these intrinsic themes of sustainable development. The development of a sustainable construction industry requires a holistic approach that takes into consideration the interaction between Lean Construction principles, socio-economic and environmental policies, technological advancement and the principles of construction or project management. Sustainable construction is a cutting-edge phenomenon, forming a component of a subjectively defined concept called sustainable development. Sustainable development can be defined in terms of attitudes and judgments to assist in ensuring long-term environmental, social and economic growth in society. The key concept of sustainable construction is Lean Construction. Lean Construction emanates from the principles of the Toyota Production System (TPS), namely the application and adaptation of the fundamental concepts and principles that focus on waste reduction, the increase in value to the customer, and continuous improvement. The focus is on the reduction of socio-economic waste, and protestation of environmental degradation by reducing carbon dioxide emission footprint. Lean principles require a fundamental change in the behaviour and attitudes of the parties involved in order to overcome barriers to cooperation. Prevalent barriers to adoption of Lean Construction in Lesotho are mainly structural - such as unavailability of financing, corruption, operational inefficiency or wastage, lack of skills and training and inefficient construction legislation and political interferences. The consequential effects of these problems trigger down to quality, cost and time of the project - which then result in an escalation of operational costs due to the cost of rework or material wastage. Factor and correlation analysis of these barriers indicate that they are highly correlated, which then poses a detrimental potential to the country’s welfare, environment and construction safety. It is, therefore, critical for Lesotho’s construction industry to develop a robust governance through bureaucracy reforms and stringent law enforcement.Keywords: construction industry, sustainable development, sustainable construction industry, lean construction, barriers to sustainable construction
Procedia PDF Downloads 2946616 The Way of the English Use of Businessmen for the ASEAN Economic Community in Chonburi Province
Authors: Kittivate Boonyopakorn
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The purposes of this study were to investigate the method of the English use of the businessmen and to study their behavior of the utilization for the ASEAN economic community. The participants were divided into the three types of the merchants including the construction contractors, the construction material traders, and SME entrepreneurs. Survey questionnaires and interviews were used in this study. The findings showed that in the type of traders, 23 of the participants are construction contractors, 121 are construction material traders, and 206 are SME entrepreneurs. The study of English in language institute is highly 51.4%. The use of Google in translating English into Thai is 41.7%. Learning English themselves is 41.1% respectively. The businessmen study English for readiness for their trade.Keywords: way of rnglish use, businessmen, ASEAN economic community, Chonburi province
Procedia PDF Downloads 2446615 GIS Based Project Management Information System for Infrastructure Projects
Authors: Riki Panchal, Debasis Sarkar
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This paper describes the work done for the GIS-based project management for different infrastructure projects. It is a review paper which gives the idea of the trends in the construction project management and various models adopted for the betterment of the project planning and execution. Traditional scheduling and progress control techniques such as bar charts and the critical path method fail to provide information pertaining to the spatial aspects of a construction project. An integrated system was developed to represent construction progress not only in terms of a CPM schedule but also in terms of a graphical representation of the construction that is synchronized with the work schedule. Hence, it is suggested to work on the common platform from where all the data can be shared and analyzed.Keywords: GIS, project management, integrated model, infrastructure project
Procedia PDF Downloads 5196614 A Study on the Construction Process and Sustainable Renewal Development of High-Rise Residential Areas in Chongqing (1978-2023)
Authors: Xiaoting Jing, Ling Huang
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After the reform and opening up, Chongqing has formed far more high-rise residential areas than other cities in its more than 40 years of urban construction. High-rise residential areas have become one of the main modern living models in Chongqing and an important carrier reflecting the city's high quality of life. Reviewing the construction process and renewal work helps understand the characteristics of high-rise residential areas in Chongqing at different stages, clarify current development demands, and look forward to the focus of future renewal work. Based on socio-economic development and policy background, the article sorts the construction process of high-rise residential areas in Chongqing into four stages: the early experimental construction period of high-rise residential areas (1978-1996), the rapid start-up period of high-rise commodity housing construction (1997-2006), the large-scale construction period of high-rise commodity housing and public rental housing (2007-2014), and the period of renewal and renovation of high-rise residential areas and step-by-step construction of quality commodity housing (2015-present). Based on the construction demands and main construction types of each stage, the article summarizes that the construction of high-rise residential areas in Chongqing features large scale, high speed, and high density. It points out that a large number of high-rise residential areas built after 2000 will become important objects of renewal and renovation in the future. Based on existing renewal work experience, it is urgent to explore a path for sustainable renewal and development in terms of policy mechanisms, digital supervision, and renewal and renovation models, leading the high-rise living in Chongqing toward high-quality development.Keywords: high-rise residential areas, construction process, renewal and renovation, Chongqing
Procedia PDF Downloads 706613 Sustainability of Widlife Community Based Natural Resource Management under Benefit Sharing Mechanism in Game Management Areas in Zambia
Authors: Darius Phiri, Moses Chibesa, Donald Zulu, Robby Kasubika
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In Zambia, wildlife is co-managed by Zambia Wildlife Authority (ZAWA) and the local communities by sharing management responsibilities and benefits derived from harvesting wildlife resources under a benefit sharing mechanism. Although the benefit sharing mechanism has been formulated under good principles, it is still facing numerous challenges. In response to these challenges, a study on the sustainability of ZAWA benefit sharing mechanism was carried out in order to assess its potential and continuity in line with community empowerment and wildlife resources management. Systematic sampling was used with a sampling intensity of 4% to administer three types of questionnaires to community members in Mumbwa Game Management Area (GMA), ZAWA officers, and to the Ministry of Tourism, Environment and Natural Resources (MTENR) staffs. The collected data was then analysed using SPSS version 16.5. The findings indicated that many people in the GMA do not participate fully because of lacking satisfactory benefits. However, the mechanism contribute to the community well-being and can still remain sustainable especially if measures to address the current challenges are put in place.Keywords: benefit sharing, concessions, licenses, poaching, local communities, sustainability
Procedia PDF Downloads 3996612 Growth Mechanism, Structural and Compositional Properties of Cu₂ZnSnS₄ (CZTS) Thin Films Deposited by Sputtering Method from a Compound Target
Authors: Sanusi Abdullahi, Musa Momoh, Abubakar Umar Moreh, Aminu Muhammad Bayawa, Olubunmi Popoola
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Kesterite-type Cu₂ZnSnS₄ (CZTS) thin films were deposited on corning glass from a single quaternary target. In this study, we investigated the growth mechanism and the influence of thin film thickness on the structural and compositional properties of CZTS films. All the four samples (as-deposited inclusive) show peaks corresponding to kesterite-type structure. The diffraction peaks of (112) are sharp and the small characteristics peaks of the kesterite structure such as (220)/ (204) and (312)/ (116) are also clearly observed in X-ray diffraction pattern. These results indicate that the quaternary CZTS would be a potential candidate for solar cell applications.Keywords: RF sputtering, Cu2ZnSnS4 thin film, annealing, growth mechanism, annealing, growth mechanism, renewable energy
Procedia PDF Downloads 3746611 An Analysis of Prefabricated Construction Waste: A Case Study Approach
Authors: H. Hakim, C. Kibert, C. Fabre, S. Monadizadeh
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Construction industry is an industry saddled with chronic problems of high waste generation. Waste management that is to ensure materials are utilized in an efficient manner would make a major contribution to mitigating the negative environmental impacts of construction waste including finite resources depletion and growing occupied landfill areas to name a few. Furthermore, ‘material resource efficiency’ has been found an economically smart approach specially when considered during the design phase. One effective strategy is to utilizing off-site construction process which includes a series of prefabricated systems such as mobile, modular, and HUD construction (Department of Housing and Urban Development manufactured buildings). These types of buildings are by nature material and resource-efficient. Despite conventional construction that is exposed to adverse weather conditions, manufactured construction production line is capable of creating repetitive units in a factory controlled environment. A factory can have several parallel projects underway with a high speed and in a timely manner which simplifies the storage of excess materials and re-allocating to the next projects. The literature reports that prefabricated construction significantly helps reduce errors, site theft, rework, and delayed problems and can ultimately lead to a considerable waste reduction. However, there is not sufficient data to quantify this reduction when it comes to a regular modular house in the U.S. Therefore, this manuscript aims to provide an analysis of waste originated from a manufactured factory trend. The analysis was made possible with several visits and data collection of Homes of Merits, a Florida Manufactured and Modular Homebuilder. The results quantify and verify a noticeable construction waste reduction.Keywords: construction waste, modular construction, prefabricated buildings, waste management
Procedia PDF Downloads 2676610 Causes of Cost Overrun in Building Construction Projects: Case Study from Al Madinah, Saudi Arabia
Authors: Z. Hamed, K. Sa'deya, E. Abdelrasheed, I. Mahamid
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The construction industry is one of the main sectors that play basic role in the urban and rural development of a society. It provides important ingredients for the development of an economy. However, many construction projects experience extensive cost overrun. This study was conducted to identify the causes of cost overrun in building construction contracts in Al Madinah, Saudi Arabia and test the importance of these causes from contractors' perspective. To achieve the study objectives, a questionnaire survey was conducted to identify and rank cost overrun causes from the perspective of contractors. The findings found that the top five cost overrun causes are: lack of experience in the line of work, lack of labor productivity, delay in payments, rework and material waste. It is hoped that the findings will guide efforts to improve the performance of construction industry in Saudi Arabia and other developing countries.Keywords: building, contractor, cost increase, cost overrun
Procedia PDF Downloads 1566609 Circular Economy: Development of Quantitative Material Wastage Management Plan for Effective Waste Reduction in Building Construction Industry
Authors: Kwok Tak Kit
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Combating climate change is becoming a hot topic in various sectors. Building construction and infrastructure sectors contributed a significant proportion of waste and GHGs emissions in the economy of different countries and cities. Many types of research had conducted and discussed the topic of waste management and waste management being a macro-level control is well developed in the building and construction industry. However, there is little research and studies on the micro-level of waste management, “building construction material wastage management,” and fewer reviews about regulatory control in the building construction sector. In this paper, we will focus on the potentialities and importance of material wastage management and review the deficiencies of the current standard to take into account the reduction of material wastage in a systematic and quantitative approach.Keywords: quantitative measurement, material wastage management plan, waste management, uncalculated waste, circular economy
Procedia PDF Downloads 1546608 A Comparative Study on the Impact of Global Warming of Applying Low Carbon Factor Concrete Products
Authors: Su-Hyun Cho, Chang-U Chae
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Environmental impact assessment techniques have been developed as a result of the worldwide efforts to reduce the environmental impact of global warming. By using the quantification method in the construction industry, it is now possible to manage the greenhouse gas is to systematically evaluate the impact on the environment over the entire construction process. In particular, the proportion of greenhouse gas emissions at the production stage of construction material occupied is high, and efforts are needed in particular in the construction field. In this study, intended for concrete products for the construction materials, by using the LCA evaluation method, we compared the results of environmental impact assessment and carbon emissions of developing products that have been applied low-carbon technologies compared to existing products. As a results, by introducing a raw material of industrial waste, showed carbon reduction. Through a comparison of the carbon emission reduction effect of low-carbon technologies, it is intended to provide academic data for the evaluation of greenhouse gases in the construction sector and the development of low-carbon technologies of the future.Keywords: CO₂ emissions, CO₂ reduction, ready-mixed concrete, environmental impact assessment
Procedia PDF Downloads 4796607 Project Time and Quality Management during Construction
Authors: Nahed Al-Hajeri
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Time and cost is an integral part of every construction plan and can affect each party’s contractual obligations. The performance of both time and cost are usually important to the client and contractor during the project. Almost all construction projects are experiencing time overrun. These time overruns always contributed as expensive to both client and contractor. Construction of any project inside the gathering centers involves complex management skills related to work force, materials, plant, machineries, new technologies etc. It also involves many agencies interdependent on each other like the vendors, structural and functional designers including various types of specialized engineers and it includes support of contractors and specialized contractors. This paper mainly highlights the types of construction delays due to which project suffer time and cost overrun. This paper also speaks about the delay causes and factors that contribute to the construction sequence delay for the oil and gas projects. Construction delay is supposed to be one of the repeated problems in the construction projects and it has an opposing effect on project success in terms of time, cost and quality. Some effective methods are identified to minimize delays in construction projects such as: 1. Site management and supervision, 2. Effective strategic planning, 3. Clear information and communication channel. Our research paper studies the types of delay with some real examples with statistic results and suggests solutions to overcome this problem.Keywords: non-compensable delay, delays caused by force majeure, compensable delay, delays caused by the owner or the owner’s representative, non-excusable delay, delay caused by the contractor or the contractor’s representative, concurrent delay, delays resulting from two separate causes at the same time
Procedia PDF Downloads 2426606 Identifying Barriers of Implementing Building Information Modelling in Construction
Authors: Kasra HosseinMostofi, Mohamadamin Oyar Hossein, Reza Mehdizadeh Anvigh
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BIM is an innovative concept for the majority of firms operating in industry. BIM offers a new paradigm to design, construct, operate, and maintain a facility. However, even with the most conscientious use, stakeholders can run into trouble during its implementation on a project or within an organization. At times, project stakeholders are unaware of the challenges that they can face with the implementation at the project level or an organizational level. Therefore, the study aimed to identify and compile barriers associated with the BIM implementation at the project and organizational level, as per the literature. Despite the fact that innumerable advantageous involved in exploiting BIM, there are some barriers to implement it properly. These barriers have been proved as impediments for academicians and members of construction team project to take the maximum advantage of its utilization. Although some research has been conducted to identify these barriers regarding BIM implementation in construction industry, more research is needed to be carried out among academicians to identify these barriers in institutions, and most importantly, to make suggestions for eliminating these obstacles.Keywords: building information modelling, construction, design and construction, designers
Procedia PDF Downloads 1856605 Towards an Intelligent Ontology Construction Cost Estimation System: Using BIM and New Rules of Measurement Techniques
Authors: F. H. Abanda, B. Kamsu-Foguem, J. H. M. Tah
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Construction cost estimation is one of the most important aspects of construction project design. For generations, the process of cost estimating has been manual, time-consuming and error-prone. This has partly led to most cost estimates to be unclear and riddled with inaccuracies that at times lead to over- or under-estimation of construction cost. The development of standard set of measurement rules that are understandable by all those involved in a construction project, have not totally solved the challenges. Emerging Building Information Modelling (BIM) technologies can exploit standard measurement methods to automate cost estimation process and improves accuracies. This requires standard measurement methods to be structured in ontologically and machine readable format; so that BIM software packages can easily read them. Most standard measurement methods are still text-based in textbooks and require manual editing into tables or Spreadsheet during cost estimation. The aim of this study is to explore the development of an ontology based on New Rules of Measurement (NRM) commonly used in the UK for cost estimation. The methodology adopted is Methontology, one of the most widely used ontology engineering methodologies. The challenges in this exploratory study are also reported and recommendations for future studies proposed.Keywords: BIM, construction projects, cost estimation, NRM, ontology
Procedia PDF Downloads 5516604 Power and Wear Reduction Using Composite Links of Crank-Rocker Mechanism with Optimum Transmission Angle
Authors: Khaled M. Khader, Mamdouh I. Elimy
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Reducing energy consumption became the major concern for all countries of the world during the recent decades. In general, power saving is currently the nominal goal of most industrial countries. It is well known that fossil fuels are the main pillar of development of world countries. Unfortunately, the increased rate of fossil fuel consumption will lead to serious problems caused by an expected depletion of fuels. Moreover, dangerous gases and vapors emission lead to severe environmental problems during fuel burning. Consequently, most engineering sectors especially the mechanical sectors are looking for improving any machine accompanied by reducing its energy consumption. Crank-Rocker planar mechanism is the most applied in mechanical systems. Besides, it is one of the most significant parts of the machines for obtaining the oscillatory motion. The transmission angle of this mechanism can be considered as an optimum value when its extreme values are equally varied around 90°. In addition, the transmission angle plays an important role in decreasing the required driving power and improving the dynamic properties of the mechanism. Hence, appropriate selection of mechanism links lengthens, which assures optimum transmission angle leads to decreasing the driving power. Moreover, mechanism's links manufactured from composite materials afford link's lightweight, which decreases the required driving torque. Furthermore, wear and corrosion problems can be treated through using composite links instead of using metal ones. This paper is dealing with improving the performance of crank-rocker mechanism using composite links due to their flexural elastic modulus values and stiffness in addition to high damping of composite materials.Keywords: Composite Material, Crank-Rocker Mechanism, Transmission angle, Design techniques, Power Saving
Procedia PDF Downloads 304