Health and Safety issues in the construction industry are of much concern to stakeholders, particularly because of their impact on the industry. This paper explored the roles and responsibilities of stakeholders in en...Health and Safety issues in the construction industry are of much concern to stakeholders, particularly because of their impact on the industry. This paper explored the roles and responsibilities of stakeholders in ensuring health and safety at the construction site. A well-structured interview guide was adopted for the qualitative study. Content analysis was adopted for the analysis of the results. The study revealed that the twelve roles identified by the stakeholders are only limited to the few laws and regulations they are aware of. Whereas the Contractors identified provision of welfare facilities, provision of health and safety policy, and health and safety plan as their key roles, the Consultants’ role was mainly limited to provision of competent site agent and provision of site layout. Abiding by the contractors’ instruction was identified by the Construction Workers as their key responsibilities. The local government officials also identified enforcement of CHS laws and regulations and reporting of incidents to the appropriate authorities, whereas the traditional authorities identified the enforcement of CHS laws and regulations including bye laws and enforcement of customs as their key roles. The findings further show that the stakeholders failed to appreciate some key roles and responsibilities enshrined in CHS laws and regulations in Ghana. The findings contribute to knowledge on stakeholders’ responsibilities in ensuring CHS, and provide valuable reference and insight to practitioners on the roles and responsibilities of the various stakeholders. It is recommended to train and educate stakeholders on all the relevant laws and regulations on CHS in order to improve health and safety at the construction site. The government should also set up a body such as Construction Authority to educate, coordinate, monitor and audit the activities of stakeholders to improve CHS at construction sites.展开更多
On the basis of the 12-year author’s practice of bank investment supervision developed methodology significant construction projects risks have been identified and measured: risks of the highest impact values and ris...On the basis of the 12-year author’s practice of bank investment supervision developed methodology significant construction projects risks have been identified and measured: risks of the highest impact values and risks of the biggest likelihood appearance. The research has been recorded in 400-450 reports of 42 investment projects in advanced manufacturing, commercial, residential, hotels and apartment housing sectors. At least one risk of the highest measured level of significance has been highlighted at each phase of investment process: design, construction and maintenance. A reasonable level of risks significance has been determined which stands for not more than 1/3 of possible significance in “risks monitoring” strategy. EPCM (engineering, project and construction management) approach to investment process and solid, consequent, regular construction projects monitoring executed by professional BSI (banking supervision inspector) makes possible to minimise any faults of inappropriate financing of construction projects.展开更多
Accurate project progress measurement is critical for effective project management. Besides guarantying smooth work progress, it affords project managers the chance to identify early warning signs for peremptory remed...Accurate project progress measurement is critical for effective project management. Besides guarantying smooth work progress, it affords project managers the chance to identify early warning signs for peremptory remedial actions to keep the project on schedule and to budget. However, pertinent barriers can suppress the realization of the benefits of an accurate assessment of construction progress. This study aims to identify, examine and prioritize the critical barriers militating against accurate project progress measurement in the Ghanaian construction industry. Sixteen barriers identified from the literature were administered in a questionnaire survey to professionals with tier one construction firms and consultants. Sixty experienced construction professionals practising with tier-one construction firms and consultancy services took part in the survey. The relative importance index technique was used to rank the factors and correlation in responses of the two parties tested by the Mann-Whitney <em>U</em> statistics. The most critical barriers perceived by the professionals were 1) Reliance on Supervisor’s Judgement, 2) Generic and Non-Systematic Approach, 3) Variable Quality of Data and 4) Intricate Measurement Reports. Other highly ranked barriers include 5) Lack of Timely Information, 6) Laborious Data Gathering and 7) Quality Integration Constraint. The findings underpin the need to minimize dependence on subjective opinions and mere experiences of supervisors for assessment of project progress in this age of information technology. Incorporation of a level of automation into traditional progress methods will not only reduce human errors introduced into manually collected data but facilitate visualization of progress reports. Contiguous to a clear specification of the method of progress measurement in the contract document, a system that conveniently integrates cost, time and scope of work into progress measurement must be pursued. Addressing these identified critical barriers will consolidate current construction progress management practices.展开更多
The primary objective of this study was to assess the use of the maturity method to determine the joint sawing window and the traffic opening time on whitetopping construction in Korea. To determine joint sawing time,...The primary objective of this study was to assess the use of the maturity method to determine the joint sawing window and the traffic opening time on whitetopping construction in Korea. To determine joint sawing time, it was necessary to find the minimum strength not to cause raveling and to identify the time to the occurrence of drying shrinkage. This study found that the minimum compressive strength for joint sawing was 4.41MPa （45kg/cm2） and drying shrinkage occurred just after the concrete temperature reached at the peak. To develop the relationship between compressive strength and maturity values, thermachron i-buttons were inserted into the top and mid-depth of the fresh concrete in the test slabs. The results of the laboratory tests indicated that the Arrhenius equation better fitted the relationship between the compressive strength and maturity values than did the Nurse-Saul equation. However, the Nurse-Saul function estimated in-place strength quite well in this study. Therefore, the Nurse-Saul equation was used to determine the joint sawing window and the traffic opening time for whitetopping construction.展开更多
Due to high construction material cost in Ethiopia,it is difficult to afford a shelter for most people.The hydra form block(HFB)has been identified as low-cost building material with its potential and possibility to r...Due to high construction material cost in Ethiopia,it is difficult to afford a shelter for most people.The hydra form block(HFB)has been identified as low-cost building material with its potential and possibility to reverse the housing problem.Laboratory tests were conducted on Mettu,Nopa,Gore,and Hurumu areas soil.Using hydra form machine with average mold size of 29*14*10 cm,hydra form blocks were cast with the three percentages increment of cement.Compressive strength and water absorption tests were conducted at 28 day.The investigation has revealed that all the soil sample except Gore soil have significant characteristics that make it suitable for stabilization with recommended soil properties.From the experimental study,all the blocks except blocks produced with Gore soil have 28th day compressive strength values well above most of the recommended minimum values.Water absorption was less than the maximum limit of 15%.But,for control block and for stabilized with 3%cement,water absorption result is out of the recommended values(0-15)%.The cost comparison of hydra form blocks with hollow concrete block and fired clay brick shows that the hydra form block is cheapest walling material in terms of production cost and a typical hydra form block production center can create jobs for more than 50 people.展开更多
The construction industry, known for its low productivity, is increasingly utilising software and mobile apps to enhance efficiency. However, more comprehensive research is needed to understand the effectiveness of th...The construction industry, known for its low productivity, is increasingly utilising software and mobile apps to enhance efficiency. However, more comprehensive research is needed to understand the effectiveness of these technology applications. The PRISMA principles utilised a scoping review methodology to ascertain pertinent studies and extract significant findings. From 2013 onwards, articles containing data on mobile applications or software designed to enhance productivity in the construction sector were obtained from multiple databases, including Emerald Insight, Science Direct, IEEE Xplore, and Google Scholar. After evaluating 2604 articles, 30 were determined to be pertinent to the study and were subsequently analysed for the review. The review identified five key themes: effectiveness, benefits, successful implementation examples, obstacles and limitations, and a comprehensive list of software and mobile apps. In addition, 71 software and mobile apps have shown potentially how these technologies can improve communication, collaboration, project management, real-time collaboration, document management, and on-the-go project information and estimating processes in the construction industry, increasing efficiency and productivity. The findings highlight the potential of these technologies such as Automation, Radio-Frequency Identification (RFID), Building Information Modeling (BIM), Augmented Reality (AR), Virtual Reality (VR), and Internet of Things (IoT) to improve efficiency and communication in the construction industry. Despite challenges such as cost, lack of awareness, resistance to change, compatibility concerns, human resources, technological and security concerns and licensing issues, the study identifies specific mobile applications and software with the potential to enhance efficiency significantly, improve productivity and streamline workflows. The broader societal impacts of construction software and mobile app development include increased efficiency, job creation, and sustainability.展开更多
The Afyon-Akşehir and Sinanpaşa grabens,located in the eastern part of the Akşehir-Simav Fault System,are important sedimentary basins in the western Anatolia,Türkiye.This region,particularly the western of Afyon...The Afyon-Akşehir and Sinanpaşa grabens,located in the eastern part of the Akşehir-Simav Fault System,are important sedimentary basins in the western Anatolia,Türkiye.This region,particularly the western of Afyon-Akşehir Graben,is a significant region known for its geothermal potential.The study focuses on analyzing gravity data to identify structural elements and examine the geological structures in the basins.The edge detection and enhancement techniques such as total horizontal gradient,tilt angle of the total horizontal gradient,enhanced dip angle and curvature analysis were used to investigate the structural lineaments in the area.Furthermore,2D/3D gravity modeling techniques were utilized to investigate the sedimentary depths of the Afyon-Akşehir and Sinanpaşa grabens.Based on the findings from the edge detection studies,three distinct linear features were highlighted in addition to previously identified geological structures.3D gravity inversion modeling reveals sedimentary basin depths of up to 470 m in Sinanpaşa Graben and 720 m in the western Afyon-Akşehir Graben.As a result of the structural mapping and 2D/3D gravity modeling studies,a structural uplift that may be linked to geothermal activity was detected among the local depressions in the Afyon-Akşehir Graben.The obtained features may be of potential interest for geothermal exploration;therefore,further investigations using additional geophysical data are recommended.展开更多
Finger-joint lumber is a sustainable building product commercialized as a structural solution for beams,pillars and other thin flat load-bearing elements.This study aims to study finger-joint lumber and its industry t...Finger-joint lumber is a sustainable building product commercialized as a structural solution for beams,pillars and other thin flat load-bearing elements.This study aims to study finger-joint lumber and its industry to promote this engineered wood product.The first research stage assessed the collection of publications on fingerjoint lumber available globally,in which a structured protocol was developed to prospect studies based on two complementary methodologies:PRISMA 2020 using Scopus and Web of Science databases,and Snowball using both forward and backward models to complete with additional literature.The second research stage assessed finger-joint lumber manufacturers,in which companies were globally prospected using Google search engine and their corporate websites were profoundly analyzed using a structured script to collect information.Literary approaches have provided structural performance and bonding quality of finger-jointing.In the review,we provide a global overview and data regarding the current stage and future directions of finger-joint lumber for industrialized construction.Regarding this structural product,we review the main resources,material preparation and processing,and automated production.Mainly active in Europe and already present in 38 nations across five continents,we survey a finger-joint lumber industry comprising 186 producers controlling 214 manufacturing operations worldwide.The vast majority of this industry has exported linear engineered solutions in different dimensions,certified as to compliance with the origins of their bioresources and the European Union requirements,to markets exposed to 24 languages in order to meet commercial applications such as single-story houses,townhouses,roof structures,and hangars.展开更多
The multiple cracking and deflection hardening performance of polyvinyl alcohol fiber reinforced engineered cementitious composites(PVA-ECC)under four-point flexural loading have been investigated.Matrices with differ...The multiple cracking and deflection hardening performance of polyvinyl alcohol fiber reinforced engineered cementitious composites(PVA-ECC)under four-point flexural loading have been investigated.Matrices with different binder combinations and W/B ratios(from 0.44 to 0.78)providing satisfactory PVA fiber dispersion were specially designed.Effect of pre-existing flaw size distribution modification on deflection hardening behavior was comparatively studied by adding 3 mm diameter polyethylene beads into the mixtures(6%by total volume).Natural flaw size distributions of composites without beads were determined by cross sectional analysis.The crack number and crack width distributions of specimens after flexural loading were characterized and the possible causes of changes in multiple cracking and deflection hardening behavior by flaw size distribution modification were discussed.Promising results from the view point of deflection hardening behavior were obtained from metakaolin incorporated and flaw size distribution modified PVA-ECCs prepared with W/B=0.53.The dual roles of W/B ratio and superplasticizer content on flaw size distribution,cracking potential and fiber-matrix bond behavior were evaluated.Flaw size distribution modification is found beneficial in terms of ductility improvement at an optimized W/B ratio.展开更多
An engineering application tool for prediction of the static equilibrium bay （ Beach Mod） is established to describe two bay shape formulas by use of the programming software ＂MATLAB＂ with a graphic user interface...An engineering application tool for prediction of the static equilibrium bay （ Beach Mod） is established to describe two bay shape formulas by use of the programming software ＂MATLAB＂ with a graphic user interface （ GUI）. The tool is user-friendly for engineering students for the design of beach shapes. This tool was tested through application on three types of beaches in Taiwan and Australia. By implementing the concept of Headland Control, the Beach Mod program allows users to draw a structure and create an ＇artificial headland. The results indicate that Beach Mod can efficiently forecast beach changes as well as MEPBAY, a competing software package, while boasting a better user interface.展开更多
This study aims to determine the key and underlying Leadership and Top Management (LTM) factors that have a significant impact on sustaining the implementation of Total Quality Management (TQM) within the construction...This study aims to determine the key and underlying Leadership and Top Management (LTM) factors that have a significant impact on sustaining the implementation of Total Quality Management (TQM) within the construction industry in Ghana. The research methodology employed in this study was a quantitative technique. Questionnaires were distributed to 641 participants within construction industry in Ghana. Questionnaires retrieved for the analysis were 536. Three steps approached were used for the data analysis. These include Exploratory Factor Analysis (EFA), Confirmatory Factor Analysis (CFA), and Structural Equation Modeling (SEM) analysis. After conducting the EFA and CFA, SEM was also used to analyze the construct validity. The SEM analysis helps to determine four key indicator variables for the leadership and top management construct. These include Leadership/Top Management approach to employees’ management, Leadership/Top Management understanding of TQM, Leadership/Top Management empowerment of employees to resolve quality issues, and Leadership/Top Management endorsement of TQM. All the four indicator variables were found to be good of fit and closely associated with the dependent variable. The study adds to the body of knowledge by using EFA, CFA and SEM techniques to establish key leadership and top management factors affecting TQM implementation in Ghana’s construction industry. The findings in general suggested that leadership and top Management factors identified have a direct positive impact on sustaining TQM implementation in the Ghanaian construction industry. Consequently, the leadership and top management factors identified in this study can help improve TQM in the Ghanaian construction industry.展开更多
The enormity of the problem of construction accidents and hazards in the Ghanaian construction industry (GCI) calls for the need to engage in relevant research to equip stakeholders with the required knowledge to impr...The enormity of the problem of construction accidents and hazards in the Ghanaian construction industry (GCI) calls for the need to engage in relevant research to equip stakeholders with the required knowledge to improve construction health and safety (CHS) and reduce site accidents and hazards. The complexity of the problem of accident causation explains a large number of conceptual models developed to aid the understanding of the dynamics involved in CHS. This paper involved a qualitative study to identify causes of accidents and hazards in the GCI and underlying issues requiring remedying and also a desk study to review Health and Safety related theories and concepts from extant literature to explain and contribute to the improvement of CHS. The paper contributes to the use of theories to advance studies on improving health and safety at construction sites, especially in developing countries like Ghana, where such studies have so far attracted little attention. The framework may enable construction stakeholders to easily identify problem areas on site and apply required improvement measures to create a healthier and safer construction site. The findings may provide useful knowledge to improve CHS and reduce site accidents and hazards, and also provide a multi-theory approach for understanding the dynamics of the complexity of the problems involved in CHS.展开更多
Construction causative nuisances, inconveniences, interferences and disruptions to the routine economic and social life patterns of adjacent or neighboring communities are referred to as social cost. This study explor...Construction causative nuisances, inconveniences, interferences and disruptions to the routine economic and social life patterns of adjacent or neighboring communities are referred to as social cost. This study explores the understanding and level of consideration of social cost by construction professionals in Ghana. Relevant literature sources are reviewed to define, rationalize and classify social cost. The study used the survey approach with a set of questionnaires addressed to construction contractors and professionals to gather the data. It was realized that not much consideration is given to social cost at the tender stage of the construction process. The five factors hindering social cost inclusion in tendering are “difficulty in allocating social costs”, “governmental interferences”, “lack of historical data”, “lack of appreciation of social costs” and “low stakeholder agitation”. The paper advocated for integration of social cost into the tendering process. The study will serve as a foundation to design a social cost assessment system at the pre-contract stage.展开更多
This paper explored stakeholders’ compliance with existing laws and regulations related to construction health and safety (CHS) in the Ghanaian construction industry (GCI). Qualitative research approach was adopted f...This paper explored stakeholders’ compliance with existing laws and regulations related to construction health and safety (CHS) in the Ghanaian construction industry (GCI). Qualitative research approach was adopted for the data collection, using semi-structured interview guide. An in-depth face-to-face interview based on the grounded theory approach was conducted with actors who play important roles in ensuring health and safety at the construction site as well as key officers and professionals who are the major stakeholders in the GCI. Content analysis was adopted for the analysis of the qualitative data. The findings of the study show customary laws, bye laws, Labour Act, 2003 (Act 651), Local Governance Act, 2016 (Act 936) and the contract document as the key existing CHS related laws and regulations that the stakeholders comply with. The stakeholders also identified the following construction health and safety related regulations in the GCI which have low compliance rate: Factories, Shops and Offices Act, 1974 (Act 323), Environmental Protection Act, 1994 (Act 490), among others. The findings of the research contribute to knowledge of stakeholders’ compliance with existing laws and regulations related to CHS, and underscore the need to ensure monitoring and enforce compliance in the GCI. The findings further identify areas for stakeholders to focus attention on ensuring good health and safety practices, and also expose critical training and education needs for stakeholders in the GCI. The findings provide valuable insights on stakeholders’ compliance with laws and regulations related to CHS in Ghana, which may be applicable to other developing countries with similar construction industry.展开更多
<div style="text-align:justify;"> Ozone plasma treatment is accessible to be applied on shading adjustment and colour fading because of the capacity of ozone production. It is a green process that trea...<div style="text-align:justify;"> Ozone plasma treatment is accessible to be applied on shading adjustment and colour fading because of the capacity of ozone production. It is a green process that treats dyed cotton fabric under dry condition so as to avoid chemical pollutants. This study means to explore colour reflectance of decolourized sulfur dyed cotton texture using ozone plasma treatment. Sulfur dyed cotton textures with various colour depths (0.5%, 1.5%, 2.5%) were set up to be treated different plasma parameters, including ozone air concentrations (10%, 30%, 50%, 70%), water contents in terms of weight percentage (35%, 45%) of fabric and ozone air plasma treatment periods (10 mins, 20 mins, 30 mins). The colour fading result is assessed by the colour reflectance in percentage (R%) utilizing spectrophotometer under CIE standard illuminant D65. The valid colour fading based on high percentage of reflectance was demonstrated from plasma treatment under higher ozone air concentration (50% and 70% ozone in air) and longer time length of plasma treatment (20 mins and 30 mins). The level of water content contained in the cotton fabrics is appeared to have noteworthy relationship with the degree of decolourization. </div>展开更多
This article aims to present an analysis of the influence of thermal bridges on reinforced concrete structural systems regarding energy performance of the envelope of a commercial building located in the bioclimatic z...This article aims to present an analysis of the influence of thermal bridges on reinforced concrete structural systems regarding energy performance of the envelope of a commercial building located in the bioclimatic zones 1 to 8 in Brazil, using computer simulation. The method used to achieve this goal includes the following steps： （1） definition and configuration of the base case; （2） definition and configuration of the reference model; （3） optimization of energy modeling; （4） energy modeling and comparison of consumption between the base case and the reference model. Main results showed that thermal bridges in reinforced concrete interfere on the building＇s energy performance and that the impact is related to the WWR （window-to-wall ratio） on the building. For hotel buildings with WWR from 30% to 45%, thermal bridges imply a decrease in estimated consumption, which can reach 10%, depending on the bioclimatic zone. For 60% WWR, the non-consideration of thermal bridges can represent up to 5% of increase in estimated consumption, depending on the Brazilian bioclimatic zone.展开更多
Decentralisation of infrastructure delivery to sub-national governments has become commonplace in governments worldwide especially in developing countries such as Ghana. This is due to the benefits of decentralisation...Decentralisation of infrastructure delivery to sub-national governments has become commonplace in governments worldwide especially in developing countries such as Ghana. This is due to the benefits of decentralisation in improving public service delivery. However, decentralised infrastructure delivery is marred with numerous challenges that render most local governments incapable of providing infrastructure within their localities. This paper explored the bureaucratic factors that impede infrastructure delivery at the MMDAs in Ghana. A questionnaire survey with 121 construction professionals in the Departments of Works (DoWs) of the MMDAs within the Ashanti and Greater Accra Regions of Ghana was conducted. The results indicated six (6) major components of the bureaucratic factors that impede the delivery of infrastructure at the MMDAs: Central government bureaucracy;Minimal control of MMDAs;Political influence;MMDA project funding;Lack of capacity of MMDAs;and Political interference. This paper calls for a more committed central government to the establishment of adequate decentralised structures and implementation of major reforms that would remove the bureaucratic obstacles in the delivery of infrastructure at the MMDAs, to ensure effective infrastructure delivery at the MMDAs.展开更多
Tender price indices (TPI) remain an optimum process for predicting tender prices. There have been several indices’ developments in the Ghanaian Building Industry (GBI) to help in cost management practices, for insta...Tender price indices (TPI) remain an optimum process for predicting tender prices. There have been several indices’ developments in the Ghanaian Building Industry (GBI) to help in cost management practices, for instance, building cost indices, and material indices among others. Notwithstanding, there are no indices for forecasting tender price at the design stage of building projects in the Ghanaian Building Industry. The motivation of this study is to develop tender price indices that would facilitate easy prediction of the initial cost of building projects. Through a thorough literature review and secondary data collection, the index was formulated using Laspeyres with Excel spreadsheet for the actual index. The variables considered include preliminaries and measured work sections which include the substructure, concrete work, reinforcement, masonry, lining/sheathing, window/door/stairs, metalwork, surface finishes, sanitary appliances/fitting and electrical supply/power light system of the Bills of Quantities. The finding of the study shows that on average there is a change in price of about 4.42 per cent within the eight-year period from 2008 to 2016. The study has developed tender price indices for the Ghanaian Building industry for the facilitation of the easy prediction of the tender prices at the initial design stage, however, the indices have an error margin of ±3. The development of these indices will serve as the basis for further development of other indices in GBI such as locational indices and value-based indices for effective cost management practices.展开更多
Natural stone aggregate forms the bulk volume of concrete and has contributed to the increased cost of concrete production. This has led to the search for alternate aggregates such as lateritic stone for concrete prod...Natural stone aggregate forms the bulk volume of concrete and has contributed to the increased cost of concrete production. This has led to the search for alternate aggregates such as lateritic stone for concrete production. This paper investigates the engineering properties of concrete produced with lateritic aggregate (LA) as the coarse aggregate replacement and coconut husk fibre (CHF) as reinforcement. Natural stone aggregate was replaced by LA at 0%, 10%, 20%, 30%, 40%, and 50%, with 0.25% constant CHF by weight. A mix proportion of 1:1.5:3 with a water-cement ratio of 0.6 was used for producing concrete. A total of 162 specimens (90 cubes and 72 beams) were prepared and tested at the 7, 14, 21, and 28 days of curing. The highest compressive strength was 43.36 N/mm2 (10% LA replacement) as compared to the control of 41.51 N/mm2. The 10% LA replacement obtained the highest flexural strength of 5.35 N/mm2 as compared with the 5.29 N/mm2 for the control. The water absorption of the concrete increased from 2.8% (control) to 3.57% (50% replacement LA). Scanning electron microscopy (SEM) revealed micro gaps between CHF and LA concrete. The study, therefore, concludes that the use of LA and CHF positively influenced the strength properties of concrete. 10% LA replacement of coarse aggregate and 0.25% CHF is recommended to practitioners for use.展开更多
This study is aimed at bringing out the salient aspects of urban noise and its study and control aspects, at different location of a metropolitans town. Field measurements at different points of times a day have also ...This study is aimed at bringing out the salient aspects of urban noise and its study and control aspects, at different location of a metropolitans town. Field measurements at different points of times a day have also been recorded at a number of high-traffic-intensity locations on main roads of towns. The data obtained are analyzed using SPSS package for calculation through ANOVA technique and the findings of these studies have been recorded. The variation of SPL considering the time of the day has been studied and illustrated through graphical plots. It shows that the peak early morning max sound pressure levels observed over the recommended limiting value. In some places, the low frequency noise predominates in the early morning hours, noise levels are significant among and within the 15 groups. The variation of sound pressure (Maximum, Minimum and L equivalent readings) levels as shown in the graphical plots, the Maximum and L equivalent levels exceeded the recommended noise level. Important conclusions of this work have been drawn subsequently.展开更多
文摘Health and Safety issues in the construction industry are of much concern to stakeholders, particularly because of their impact on the industry. This paper explored the roles and responsibilities of stakeholders in ensuring health and safety at the construction site. A well-structured interview guide was adopted for the qualitative study. Content analysis was adopted for the analysis of the results. The study revealed that the twelve roles identified by the stakeholders are only limited to the few laws and regulations they are aware of. Whereas the Contractors identified provision of welfare facilities, provision of health and safety policy, and health and safety plan as their key roles, the Consultants’ role was mainly limited to provision of competent site agent and provision of site layout. Abiding by the contractors’ instruction was identified by the Construction Workers as their key responsibilities. The local government officials also identified enforcement of CHS laws and regulations and reporting of incidents to the appropriate authorities, whereas the traditional authorities identified the enforcement of CHS laws and regulations including bye laws and enforcement of customs as their key roles. The findings further show that the stakeholders failed to appreciate some key roles and responsibilities enshrined in CHS laws and regulations in Ghana. The findings contribute to knowledge on stakeholders’ responsibilities in ensuring CHS, and provide valuable reference and insight to practitioners on the roles and responsibilities of the various stakeholders. It is recommended to train and educate stakeholders on all the relevant laws and regulations on CHS in order to improve health and safety at the construction site. The government should also set up a body such as Construction Authority to educate, coordinate, monitor and audit the activities of stakeholders to improve CHS at construction sites.
文摘On the basis of the 12-year author’s practice of bank investment supervision developed methodology significant construction projects risks have been identified and measured: risks of the highest impact values and risks of the biggest likelihood appearance. The research has been recorded in 400-450 reports of 42 investment projects in advanced manufacturing, commercial, residential, hotels and apartment housing sectors. At least one risk of the highest measured level of significance has been highlighted at each phase of investment process: design, construction and maintenance. A reasonable level of risks significance has been determined which stands for not more than 1/3 of possible significance in “risks monitoring” strategy. EPCM (engineering, project and construction management) approach to investment process and solid, consequent, regular construction projects monitoring executed by professional BSI (banking supervision inspector) makes possible to minimise any faults of inappropriate financing of construction projects.
文摘Accurate project progress measurement is critical for effective project management. Besides guarantying smooth work progress, it affords project managers the chance to identify early warning signs for peremptory remedial actions to keep the project on schedule and to budget. However, pertinent barriers can suppress the realization of the benefits of an accurate assessment of construction progress. This study aims to identify, examine and prioritize the critical barriers militating against accurate project progress measurement in the Ghanaian construction industry. Sixteen barriers identified from the literature were administered in a questionnaire survey to professionals with tier one construction firms and consultants. Sixty experienced construction professionals practising with tier-one construction firms and consultancy services took part in the survey. The relative importance index technique was used to rank the factors and correlation in responses of the two parties tested by the Mann-Whitney <em>U</em> statistics. The most critical barriers perceived by the professionals were 1) Reliance on Supervisor’s Judgement, 2) Generic and Non-Systematic Approach, 3) Variable Quality of Data and 4) Intricate Measurement Reports. Other highly ranked barriers include 5) Lack of Timely Information, 6) Laborious Data Gathering and 7) Quality Integration Constraint. The findings underpin the need to minimize dependence on subjective opinions and mere experiences of supervisors for assessment of project progress in this age of information technology. Incorporation of a level of automation into traditional progress methods will not only reduce human errors introduced into manually collected data but facilitate visualization of progress reports. Contiguous to a clear specification of the method of progress measurement in the contract document, a system that conveniently integrates cost, time and scope of work into progress measurement must be pursued. Addressing these identified critical barriers will consolidate current construction progress management practices.
文摘The primary objective of this study was to assess the use of the maturity method to determine the joint sawing window and the traffic opening time on whitetopping construction in Korea. To determine joint sawing time, it was necessary to find the minimum strength not to cause raveling and to identify the time to the occurrence of drying shrinkage. This study found that the minimum compressive strength for joint sawing was 4.41MPa （45kg/cm2） and drying shrinkage occurred just after the concrete temperature reached at the peak. To develop the relationship between compressive strength and maturity values, thermachron i-buttons were inserted into the top and mid-depth of the fresh concrete in the test slabs. The results of the laboratory tests indicated that the Arrhenius equation better fitted the relationship between the compressive strength and maturity values than did the Nurse-Saul equation. However, the Nurse-Saul function estimated in-place strength quite well in this study. Therefore, the Nurse-Saul equation was used to determine the joint sawing window and the traffic opening time for whitetopping construction.
文摘Due to high construction material cost in Ethiopia,it is difficult to afford a shelter for most people.The hydra form block(HFB)has been identified as low-cost building material with its potential and possibility to reverse the housing problem.Laboratory tests were conducted on Mettu,Nopa,Gore,and Hurumu areas soil.Using hydra form machine with average mold size of 29*14*10 cm,hydra form blocks were cast with the three percentages increment of cement.Compressive strength and water absorption tests were conducted at 28 day.The investigation has revealed that all the soil sample except Gore soil have significant characteristics that make it suitable for stabilization with recommended soil properties.From the experimental study,all the blocks except blocks produced with Gore soil have 28th day compressive strength values well above most of the recommended minimum values.Water absorption was less than the maximum limit of 15%.But,for control block and for stabilized with 3%cement,water absorption result is out of the recommended values(0-15)%.The cost comparison of hydra form blocks with hollow concrete block and fired clay brick shows that the hydra form block is cheapest walling material in terms of production cost and a typical hydra form block production center can create jobs for more than 50 people.
文摘The construction industry, known for its low productivity, is increasingly utilising software and mobile apps to enhance efficiency. However, more comprehensive research is needed to understand the effectiveness of these technology applications. The PRISMA principles utilised a scoping review methodology to ascertain pertinent studies and extract significant findings. From 2013 onwards, articles containing data on mobile applications or software designed to enhance productivity in the construction sector were obtained from multiple databases, including Emerald Insight, Science Direct, IEEE Xplore, and Google Scholar. After evaluating 2604 articles, 30 were determined to be pertinent to the study and were subsequently analysed for the review. The review identified five key themes: effectiveness, benefits, successful implementation examples, obstacles and limitations, and a comprehensive list of software and mobile apps. In addition, 71 software and mobile apps have shown potentially how these technologies can improve communication, collaboration, project management, real-time collaboration, document management, and on-the-go project information and estimating processes in the construction industry, increasing efficiency and productivity. The findings highlight the potential of these technologies such as Automation, Radio-Frequency Identification (RFID), Building Information Modeling (BIM), Augmented Reality (AR), Virtual Reality (VR), and Internet of Things (IoT) to improve efficiency and communication in the construction industry. Despite challenges such as cost, lack of awareness, resistance to change, compatibility concerns, human resources, technological and security concerns and licensing issues, the study identifies specific mobile applications and software with the potential to enhance efficiency significantly, improve productivity and streamline workflows. The broader societal impacts of construction software and mobile app development include increased efficiency, job creation, and sustainability.
文摘The Afyon-Akşehir and Sinanpaşa grabens,located in the eastern part of the Akşehir-Simav Fault System,are important sedimentary basins in the western Anatolia,Türkiye.This region,particularly the western of Afyon-Akşehir Graben,is a significant region known for its geothermal potential.The study focuses on analyzing gravity data to identify structural elements and examine the geological structures in the basins.The edge detection and enhancement techniques such as total horizontal gradient,tilt angle of the total horizontal gradient,enhanced dip angle and curvature analysis were used to investigate the structural lineaments in the area.Furthermore,2D/3D gravity modeling techniques were utilized to investigate the sedimentary depths of the Afyon-Akşehir and Sinanpaşa grabens.Based on the findings from the edge detection studies,three distinct linear features were highlighted in addition to previously identified geological structures.3D gravity inversion modeling reveals sedimentary basin depths of up to 470 m in Sinanpaşa Graben and 720 m in the western Afyon-Akşehir Graben.As a result of the structural mapping and 2D/3D gravity modeling studies,a structural uplift that may be linked to geothermal activity was detected among the local depressions in the Afyon-Akşehir Graben.The obtained features may be of potential interest for geothermal exploration;therefore,further investigations using additional geophysical data are recommended.
基金supported by the Scientific Grant Agency of the Ministry of Education,Science,Research and Sport of the Slovak Republic(VEGA)with VEGA 1/0228/24 Project and the Cultural and Educational Grant Agency Ministry of Education,Science,Research and Sport of the Slovak Republic(KEGA)with KEGA 017TUKE-4/2024 ProjectBrazilian Federal Agency for Support and Evaluation of Graduate Education(CAPES),with finance code 001.
文摘Finger-joint lumber is a sustainable building product commercialized as a structural solution for beams,pillars and other thin flat load-bearing elements.This study aims to study finger-joint lumber and its industry to promote this engineered wood product.The first research stage assessed the collection of publications on fingerjoint lumber available globally,in which a structured protocol was developed to prospect studies based on two complementary methodologies:PRISMA 2020 using Scopus and Web of Science databases,and Snowball using both forward and backward models to complete with additional literature.The second research stage assessed finger-joint lumber manufacturers,in which companies were globally prospected using Google search engine and their corporate websites were profoundly analyzed using a structured script to collect information.Literary approaches have provided structural performance and bonding quality of finger-jointing.In the review,we provide a global overview and data regarding the current stage and future directions of finger-joint lumber for industrialized construction.Regarding this structural product,we review the main resources,material preparation and processing,and automated production.Mainly active in Europe and already present in 38 nations across five continents,we survey a finger-joint lumber industry comprising 186 producers controlling 214 manufacturing operations worldwide.The vast majority of this industry has exported linear engineered solutions in different dimensions,certified as to compliance with the origins of their bioresources and the European Union requirements,to markets exposed to 24 languages in order to meet commercial applications such as single-story houses,townhouses,roof structures,and hangars.
基金Project(114M246)supported by the Scientific and Technological Research Council of Turkey
文摘The multiple cracking and deflection hardening performance of polyvinyl alcohol fiber reinforced engineered cementitious composites(PVA-ECC)under four-point flexural loading have been investigated.Matrices with different binder combinations and W/B ratios(from 0.44 to 0.78)providing satisfactory PVA fiber dispersion were specially designed.Effect of pre-existing flaw size distribution modification on deflection hardening behavior was comparatively studied by adding 3 mm diameter polyethylene beads into the mixtures(6%by total volume).Natural flaw size distributions of composites without beads were determined by cross sectional analysis.The crack number and crack width distributions of specimens after flexural loading were characterized and the possible causes of changes in multiple cracking and deflection hardening behavior by flaw size distribution modification were discussed.Promising results from the view point of deflection hardening behavior were obtained from metakaolin incorporated and flaw size distribution modified PVA-ECCs prepared with W/B=0.53.The dual roles of W/B ratio and superplasticizer content on flaw size distribution,cracking potential and fiber-matrix bond behavior were evaluated.Flaw size distribution modification is found beneficial in terms of ductility improvement at an optimized W/B ratio.
文摘An engineering application tool for prediction of the static equilibrium bay （ Beach Mod） is established to describe two bay shape formulas by use of the programming software ＂MATLAB＂ with a graphic user interface （ GUI）. The tool is user-friendly for engineering students for the design of beach shapes. This tool was tested through application on three types of beaches in Taiwan and Australia. By implementing the concept of Headland Control, the Beach Mod program allows users to draw a structure and create an ＇artificial headland. The results indicate that Beach Mod can efficiently forecast beach changes as well as MEPBAY, a competing software package, while boasting a better user interface.
文摘This study aims to determine the key and underlying Leadership and Top Management (LTM) factors that have a significant impact on sustaining the implementation of Total Quality Management (TQM) within the construction industry in Ghana. The research methodology employed in this study was a quantitative technique. Questionnaires were distributed to 641 participants within construction industry in Ghana. Questionnaires retrieved for the analysis were 536. Three steps approached were used for the data analysis. These include Exploratory Factor Analysis (EFA), Confirmatory Factor Analysis (CFA), and Structural Equation Modeling (SEM) analysis. After conducting the EFA and CFA, SEM was also used to analyze the construct validity. The SEM analysis helps to determine four key indicator variables for the leadership and top management construct. These include Leadership/Top Management approach to employees’ management, Leadership/Top Management understanding of TQM, Leadership/Top Management empowerment of employees to resolve quality issues, and Leadership/Top Management endorsement of TQM. All the four indicator variables were found to be good of fit and closely associated with the dependent variable. The study adds to the body of knowledge by using EFA, CFA and SEM techniques to establish key leadership and top management factors affecting TQM implementation in Ghana’s construction industry. The findings in general suggested that leadership and top Management factors identified have a direct positive impact on sustaining TQM implementation in the Ghanaian construction industry. Consequently, the leadership and top management factors identified in this study can help improve TQM in the Ghanaian construction industry.
文摘The enormity of the problem of construction accidents and hazards in the Ghanaian construction industry (GCI) calls for the need to engage in relevant research to equip stakeholders with the required knowledge to improve construction health and safety (CHS) and reduce site accidents and hazards. The complexity of the problem of accident causation explains a large number of conceptual models developed to aid the understanding of the dynamics involved in CHS. This paper involved a qualitative study to identify causes of accidents and hazards in the GCI and underlying issues requiring remedying and also a desk study to review Health and Safety related theories and concepts from extant literature to explain and contribute to the improvement of CHS. The paper contributes to the use of theories to advance studies on improving health and safety at construction sites, especially in developing countries like Ghana, where such studies have so far attracted little attention. The framework may enable construction stakeholders to easily identify problem areas on site and apply required improvement measures to create a healthier and safer construction site. The findings may provide useful knowledge to improve CHS and reduce site accidents and hazards, and also provide a multi-theory approach for understanding the dynamics of the complexity of the problems involved in CHS.
文摘Construction causative nuisances, inconveniences, interferences and disruptions to the routine economic and social life patterns of adjacent or neighboring communities are referred to as social cost. This study explores the understanding and level of consideration of social cost by construction professionals in Ghana. Relevant literature sources are reviewed to define, rationalize and classify social cost. The study used the survey approach with a set of questionnaires addressed to construction contractors and professionals to gather the data. It was realized that not much consideration is given to social cost at the tender stage of the construction process. The five factors hindering social cost inclusion in tendering are “difficulty in allocating social costs”, “governmental interferences”, “lack of historical data”, “lack of appreciation of social costs” and “low stakeholder agitation”. The paper advocated for integration of social cost into the tendering process. The study will serve as a foundation to design a social cost assessment system at the pre-contract stage.
文摘This paper explored stakeholders’ compliance with existing laws and regulations related to construction health and safety (CHS) in the Ghanaian construction industry (GCI). Qualitative research approach was adopted for the data collection, using semi-structured interview guide. An in-depth face-to-face interview based on the grounded theory approach was conducted with actors who play important roles in ensuring health and safety at the construction site as well as key officers and professionals who are the major stakeholders in the GCI. Content analysis was adopted for the analysis of the qualitative data. The findings of the study show customary laws, bye laws, Labour Act, 2003 (Act 651), Local Governance Act, 2016 (Act 936) and the contract document as the key existing CHS related laws and regulations that the stakeholders comply with. The stakeholders also identified the following construction health and safety related regulations in the GCI which have low compliance rate: Factories, Shops and Offices Act, 1974 (Act 323), Environmental Protection Act, 1994 (Act 490), among others. The findings of the research contribute to knowledge of stakeholders’ compliance with existing laws and regulations related to CHS, and underscore the need to ensure monitoring and enforce compliance in the GCI. The findings further identify areas for stakeholders to focus attention on ensuring good health and safety practices, and also expose critical training and education needs for stakeholders in the GCI. The findings provide valuable insights on stakeholders’ compliance with laws and regulations related to CHS in Ghana, which may be applicable to other developing countries with similar construction industry.
文摘<div style="text-align:justify;"> Ozone plasma treatment is accessible to be applied on shading adjustment and colour fading because of the capacity of ozone production. It is a green process that treats dyed cotton fabric under dry condition so as to avoid chemical pollutants. This study means to explore colour reflectance of decolourized sulfur dyed cotton texture using ozone plasma treatment. Sulfur dyed cotton textures with various colour depths (0.5%, 1.5%, 2.5%) were set up to be treated different plasma parameters, including ozone air concentrations (10%, 30%, 50%, 70%), water contents in terms of weight percentage (35%, 45%) of fabric and ozone air plasma treatment periods (10 mins, 20 mins, 30 mins). The colour fading result is assessed by the colour reflectance in percentage (R%) utilizing spectrophotometer under CIE standard illuminant D65. The valid colour fading based on high percentage of reflectance was demonstrated from plasma treatment under higher ozone air concentration (50% and 70% ozone in air) and longer time length of plasma treatment (20 mins and 30 mins). The level of water content contained in the cotton fabrics is appeared to have noteworthy relationship with the degree of decolourization. </div>
文摘This article aims to present an analysis of the influence of thermal bridges on reinforced concrete structural systems regarding energy performance of the envelope of a commercial building located in the bioclimatic zones 1 to 8 in Brazil, using computer simulation. The method used to achieve this goal includes the following steps： （1） definition and configuration of the base case; （2） definition and configuration of the reference model; （3） optimization of energy modeling; （4） energy modeling and comparison of consumption between the base case and the reference model. Main results showed that thermal bridges in reinforced concrete interfere on the building＇s energy performance and that the impact is related to the WWR （window-to-wall ratio） on the building. For hotel buildings with WWR from 30% to 45%, thermal bridges imply a decrease in estimated consumption, which can reach 10%, depending on the bioclimatic zone. For 60% WWR, the non-consideration of thermal bridges can represent up to 5% of increase in estimated consumption, depending on the Brazilian bioclimatic zone.
文摘Decentralisation of infrastructure delivery to sub-national governments has become commonplace in governments worldwide especially in developing countries such as Ghana. This is due to the benefits of decentralisation in improving public service delivery. However, decentralised infrastructure delivery is marred with numerous challenges that render most local governments incapable of providing infrastructure within their localities. This paper explored the bureaucratic factors that impede infrastructure delivery at the MMDAs in Ghana. A questionnaire survey with 121 construction professionals in the Departments of Works (DoWs) of the MMDAs within the Ashanti and Greater Accra Regions of Ghana was conducted. The results indicated six (6) major components of the bureaucratic factors that impede the delivery of infrastructure at the MMDAs: Central government bureaucracy;Minimal control of MMDAs;Political influence;MMDA project funding;Lack of capacity of MMDAs;and Political interference. This paper calls for a more committed central government to the establishment of adequate decentralised structures and implementation of major reforms that would remove the bureaucratic obstacles in the delivery of infrastructure at the MMDAs, to ensure effective infrastructure delivery at the MMDAs.
文摘Tender price indices (TPI) remain an optimum process for predicting tender prices. There have been several indices’ developments in the Ghanaian Building Industry (GBI) to help in cost management practices, for instance, building cost indices, and material indices among others. Notwithstanding, there are no indices for forecasting tender price at the design stage of building projects in the Ghanaian Building Industry. The motivation of this study is to develop tender price indices that would facilitate easy prediction of the initial cost of building projects. Through a thorough literature review and secondary data collection, the index was formulated using Laspeyres with Excel spreadsheet for the actual index. The variables considered include preliminaries and measured work sections which include the substructure, concrete work, reinforcement, masonry, lining/sheathing, window/door/stairs, metalwork, surface finishes, sanitary appliances/fitting and electrical supply/power light system of the Bills of Quantities. The finding of the study shows that on average there is a change in price of about 4.42 per cent within the eight-year period from 2008 to 2016. The study has developed tender price indices for the Ghanaian Building industry for the facilitation of the easy prediction of the tender prices at the initial design stage, however, the indices have an error margin of ±3. The development of these indices will serve as the basis for further development of other indices in GBI such as locational indices and value-based indices for effective cost management practices.
文摘Natural stone aggregate forms the bulk volume of concrete and has contributed to the increased cost of concrete production. This has led to the search for alternate aggregates such as lateritic stone for concrete production. This paper investigates the engineering properties of concrete produced with lateritic aggregate (LA) as the coarse aggregate replacement and coconut husk fibre (CHF) as reinforcement. Natural stone aggregate was replaced by LA at 0%, 10%, 20%, 30%, 40%, and 50%, with 0.25% constant CHF by weight. A mix proportion of 1:1.5:3 with a water-cement ratio of 0.6 was used for producing concrete. A total of 162 specimens (90 cubes and 72 beams) were prepared and tested at the 7, 14, 21, and 28 days of curing. The highest compressive strength was 43.36 N/mm2 (10% LA replacement) as compared to the control of 41.51 N/mm2. The 10% LA replacement obtained the highest flexural strength of 5.35 N/mm2 as compared with the 5.29 N/mm2 for the control. The water absorption of the concrete increased from 2.8% (control) to 3.57% (50% replacement LA). Scanning electron microscopy (SEM) revealed micro gaps between CHF and LA concrete. The study, therefore, concludes that the use of LA and CHF positively influenced the strength properties of concrete. 10% LA replacement of coarse aggregate and 0.25% CHF is recommended to practitioners for use.
文摘This study is aimed at bringing out the salient aspects of urban noise and its study and control aspects, at different location of a metropolitans town. Field measurements at different points of times a day have also been recorded at a number of high-traffic-intensity locations on main roads of towns. The data obtained are analyzed using SPSS package for calculation through ANOVA technique and the findings of these studies have been recorded. The variation of SPL considering the time of the day has been studied and illustrated through graphical plots. It shows that the peak early morning max sound pressure levels observed over the recommended limiting value. In some places, the low frequency noise predominates in the early morning hours, noise levels are significant among and within the 15 groups. The variation of sound pressure (Maximum, Minimum and L equivalent readings) levels as shown in the graphical plots, the Maximum and L equivalent levels exceeded the recommended noise level. Important conclusions of this work have been drawn subsequently.
