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Impact of Rainfall on the Productivity of Highway Construction
Abstract
Heavy rainfall often leads to complete suspension of highway construction due to saturated and unworkable soil conditions. Therefore, quantifying the impact of rainfall on the productivity of highway con- struction is essential in preparing realistic schedules and cost estimates for the preconstruction stage and in analyzing weather-related claims for the postconstruction stage. This paper presents a decision support system for quantifying the impact of rainfall on productivity and duration of common highway construction operations, namely: earthmoving, construction of base courses, construction of drainage layers, and paving operations. The system incorporates a knowledgebase and a database. The knowledgebase includes if/then type rules, acquired from experts in highway construction operations, and the database contains hourly records of weather parameters from the closest weather station to the construction site. The system, named WEATHER, is a software system that provides user-friendly interface, including menus, dialog boxes, and graphical capabilities to facilitate data input and output.
... The BRT study has been one of the most popularly cited studies. Accordingly, the study has been criticized by many 1992), Schwartzkopf (1995), arew (1998), Brunies andEmir (2001), andSeals andRodriguez (2006), to name a few. It is suspected that the curves were not formulated based on the Procter & Gamble project data. ...
... In clear whether the project ever had periods of normal work schedules, which would have been the basis for productivity comparison. Larew (1998) indicates that the BRT data are, in general, equal to or slightly less than th th ...
... *Adapted from Hanna and Sullivan (2004). 25 The authors are referring to Larew, Richard E. (1998), who has reviewed some previous overtime literature and m e of 0 to 52.5% is simply referring to the NECA 1969 data (See Table 3, p25 of Larew (1998)). ...
... Increasing the water content of a concrete mix will have negative results. Asphalt paving operations have similar temperature thresholds but are more susceptible to small amounts of precipitation in the form of rain, snow, or hail [58]. Spreading an aggregate mix under wet conditions is difficult, and freezing temperatures can increase viscosity too quickly [54]. ...
... Construction impact models use stochastic weather model results to determine impacts on many construction factors, such as worker productivity. One notable model is the WEATHER model, which analyzes the impact of weather-related events on worker productivity [58]. Hot and humid climates produce a significant delay stemming from the change in weather [42]. ...
... Construction impact models viewing the effect of weather-related events on worker productivity [24,58,[88][89][90], construction materials [24,58,88,89], and construction processes [20,38,42,[91][92][93][94][95]. Construction impact models that focus on worker productivity are regression-based and only consider single weather factors [23,57,[88][89][90]. ...
Adverse weather delays forty-five percent of construction projects worldwide, costing project owners and contractors billions of dollars in additional expenses and lost revenue each year. Additionally, changes in climate are expected to increase the frequency and intensity of weather conditions that cause these construction delays. Researchers have investigated the effect of weather on several aspects of construction. Still, no previous study comprehensively (1) identifies and quantifies the risks weather imposes on construction projects, (2) categorizes modeling and simulation approaches developed, and (3) summarizes mitigation strategies and adaptation techniques to provide best management practices for the construction industry. This paper accomplishes these goals through a systematic state-of-the-art review of 3207 articles published between 1972 and October 2020. This review identified extreme temperatures, precipitation, and high winds as the most impactful weather conditions on construction. Despite the prevalence of climate-focused delay studies, existing research fails to account for future climate in the modeling and identification of delay mitigation strategies. Accordingly, planners and project managers can use this research to identify weather-vulnerable activities, account for changing climate in projects, and build administrative or organizational capacity to assist in mitigating weather delays in construction. The cumulative contribution of this review will enable sustainable construction scheduling that is robust to a changing climate.
... Regression-based models have been used to study earthmoving productivity [10], masonry productivity [11,12] and pile construction productivity [13]. Examples of employing expert systems for productivity modeling include the system developed by Fayek and Oduba [14] as well as El-Rayes and Mosehli [15]. Such techniques as the artificial neural network have also been involved [13,16,17]. ...
... The analysis of responses allowed four characteristic groups to be specified. Of all the factors, the lowest mean evaluation was given to c 3 , c 10 , c 14 , and c 15 . Their values are included in the range <3.09, . . . ...
... + 0.2 · 0.25 + 0.88 · 0.5 + 0.07 · 0.5 0.75 + 0.5 + 0.25 + . . . + 0.25 + 0.5 + 0.5 (15) giving the final result Wp = 1.04. The standard working time retrieved from the available directories, taking into account average working conditions, is 0.769 m 2 /w-h. ...
The aim of this study is to build a mathematical model of the productivity of construction workers. It does so by selecting 17 factors that influence the productivity of construction workers and categorising them into five groups. For the mathematical description of the factors, fuzzy logic was used. A formula for calculating the work productivity of construction workers is proposed. The novelty of the approach proposed by the authors is rooted in the consideration of various factors that have the potential to influence the productivity of construction workers. To present the way the formula operates, a single assessment of ceiling formwork was undertaken. The verification of a model confirmed its capability of analyzing, evaluating, and predicting the productivity of construction workers with satisfying accuracy.
... Among common causes of project delays, weather is consistently rated as one of the most frequent and harmful (Assaf and Al-Hejji 2006, AlSehaimi and Koskela 2008, Orangi et al. 2011, Mentis 2015. Weather can impact construction projects in multiple ways: by decreasing productivity and sometimes halting construction (Rogalska et al. 2006); by ruining unprotected and exposed constructed elements (El-Rayes and Moselhi 2001), by disrupting communications and/or blocking access to site locations (Alarc on et al. 2005), to cite but a few. Moreover, weather-related claims are a frequent source of dispute between contractors and project owners El-Rayes 2002, Nguyen et al. 2010). ...
... By way of explanation for the values chosen, earthwork activities are more difficult to execute when the ground is partially or totally frozen (Shahin et al. 2011(Shahin et al. , 2014 or when too much water causes a slope to become partially unstable (NCHRP 1978, El-Rayes andMoselhi 2001). ...
... Finally, asphalt pavements are very susceptible to the addition of small quantities of water (in the form of rain, snow or hail) (El-Rayes and Moselhi 2001, Apipattanavis et al. 2010, and to extremely high and low temperatures (NCHRP 1978). ...
The impact of (adverse) weather is a common cause of delays, legal claims and economic losses in construction projects. Research has recently been carried out aimed at incorporating the effect of weather in project planning; but these studies have focussed on either a narrow set of weather variables, or a very limited range of construction activities or projects. A method for processing a country’s historical weather data into a set of weather delay maps for some representative standard construction activities is proposed. Namely, sine curves are used to associate daily combinations of weather variables to delay and provide coefficients for expected productivity losses. A complete case study comprising the construction of these maps and the associated sine waves for the UK is presented along with an example of their use in building construction planning. Findings of this study indicate that UK weather extends project durations by an average of 21%. However, using climatological data derived from weather observations when planning could lead to average reductions in project durations of 16%, with proportional reductions in indirect and overhead costs.
... Weather is one of the major factors that can have a major influence on construction operations. Several studied focused on the effect of different weather attributes, such as temperature, rain, wind speed etc.., on the production rates in construction sites [4][5][6][7][8][9][10] . For instance, a study by Koehn and Brown showed that the maximum productivity can be achieved in a temperature range of 50°F to 80°F [4] . ...
... Other research focused on the impacts of rainfall; one study showed that rainfall can affect construction operations for days after it stops due to the water absorbed by the materials stored on site [7] . Due to the correlation between the impacts of different weather conditions on production rates, other studies focused on the development of comprehensive models for assessing the impacts of different weather attributes collectively including rain, temperature, windspeed, and snow on different construction operations [8][9][10] . ...
The literature mentions multiple factors that can affect the accuracy of estimating the project duration in highway construction, such as weather, location, and soil conditions. However, there are other factors that have not been explored, yet they can have significant impact on the accuracy of the project time estimate. Recently, TxDOT raised a concern regarding the importance of the proper estimating of the lead/lag times in project schedules. These lead/lag times are often determined based on the engineer’s experience. However, inaccurate estimates of the lead/lag time can result in unrealistic project durations. In order to investigate this claim, the study utilizes four time sensitivity measures (TSM), namely the Criticality Index (CI), Significance Index (SI), Cruciality Index (CRI), and the Schedule Sensitivity Index (SSI) to statistically analyze and draw conclusions regarding the impact of the lead/lag time estimates on the total duration in highway projects. An Excel-based scheduling software was developed with Monte Carlo simulation capabilities to calculate these TSM. The results from this paper show that the variability of some lead/lag times can significantly impact the accuracy of the estimated total project duration. It was concluded that the current practices used for estimating the lead/lag times are insufficient. As such, it is recommended to utilize more robust methods, such as the time sensitivity measures, to accurately estimate the lead/lad times in the projects scheduled.
... Construction projects are executed in an outdoor environment, most of its activities being conducted by workers outdoors (Al Shebani and Wedawattab, 2014) and therefore, are affected by various weather conditions (El-Rayes and Moselhi, 2001). Weather events such as extreme cold, heat, wind, snowfall or precipitation are recognized among the factors causing noticeable project delays, cost overruns, and contractual claims. ...
... Studies also indicate that temperatures above 110° F and below -10° F with humidity above 50% are intolerable, and it is difficult to achieve construction operations (Kohen and Brown, 1985). Though extreme weather condition in construction projects is recognized as one of the factors causing the productivity to fall, producing noticeable project delays, cost overruns, waste of resources and contractual claims (Apipattanavis, et al., 2010;Chan and Au, 2008;El-Rayes and Moselhi, 2001;Lee et al., 2017), it is also reported to be one of the main factors that influence financial performance and business continuity (Moselhi, Gong, and El-Rayes, 1997;Al Shebani and Wedawattab, 2014;Guo, Chen, and Chiu, 2017). ...
... Climate change is an emerging environmental concern that introduces various risk factors affecting outdoor construction workers, including heightened temperatures at industrial sites, increased ultraviolet exposure, and susceptibility to diseases [1]. Given the predominantly outdoor nature of construction work, these workers are consistently exposed to climatic conditions, thereby facing heightened risks, especially in extreme climates [2]. Environmental factors such as extreme temperatures, humidity, and precipitation increase human error rates, consequently affecting worker safety and productivity [3,4]. ...
The impact of climate on construction site safety varies significantly depending on subcontractor types due to the diverse nature of workplaces and work methods. This study introduces a novel approach by categorizing construction work according to subcontractor types and assessing accident risk probabilistically through the Physiologically Equivalent Temperature (PET), an outdoor thermal comfort index. Additionally, a Hidden Markov Model (HMM)-based clustering methodology was proposed to classify new groups using PET and accident probability. This study proceeded in the following sequence: (i) collection and classification of data, (ii) PET calculation, (iii) calculation of accident probability, and (iv) clustering and Pearson correlation coefficient analysis. As a result of clustering, each group was classified according to the workplace. Groups 2 and 3 demonstrated a strong positive correlation between accident probability and PET, with correlation coefficients of 0.837 and 0.772, while Group 1 exhibited a moderately positive correlation of 0.474. This study quantitatively evaluated the impact of climate on workers for each subcontractor type using PET, an outdoor thermal comfort index for construction work, and accident probability, resulting in the identification of new groups. The findings of this study may serve as novel benchmarks for safety management in construction worker safety based on PET.
... In another study, Ghoddousi et al. (2015) ranked weather as the top 16 among 32 other factors that contribute to low productivity. El-Rayes and Moselhi (2001) evaluated the impact of rainfall on the productivity of highway projects and proposed a system to predict the impact. The extreme hot climate is a major factor affecting labour productivity in Bahrain, Oman, and Nigeria (Jarkas, 2015;Jarkas et al., 2015;Muhammad et al., 2015). ...
Purpose
Weather is one of the main factors affecting labour productivity. Existing weather-productivity models focussed on hot and cold climates paying less attention to the tropics. Many tropical countries are expected to be the most areas affected by accelerated climate change and global warming, which may have a severe impact on labour health and productivity. The purpose of this paper is to assess whether the existing models can be used to predict labour productivity based on weather conditions in the tropics.
Design/methodology/approach
Five models are identified from the literature for evaluation. Using real labour productivity data of a high-rise building project in Malaysia, the actual productivity rate was compared with predicted productivity rates generated using the five models. The predicted productivity rates were generated using weather variables collected from an adjusting weather station to the project.
Findings
Compared with other models evaluated in this paper, the United States Army Corps of Engineers (USACE) was found to be the best model to predict productivity based on the case study data. However, the result shows only a 57% accuracy level of the USACE model indicating the need to develop a new model for the tropics for more accurate prediction.
Originality/value
The result of this study is perhaps the first to apply meteorological variables to predict productivity rates and validate them using actual productivity data in the tropics. This study is the first step to developing a more accurate productivity model, which will be useful for project planning and more accurate productivity rate estimation.
... Rain is one of the most important climatic factors that affects human life, Earth's ecosystem, and the profitability of various businesses including the hospitality (Franzoni and Pelizzari 2019), aviation (Bolgiani et al. 2018), and construction industries (El-Rayes and Moselhi 2001). Several industrial and national organizations have been considering property damage from rain water as a critical issue, while precipitation forecasting is being prioritized in weather studies. ...
Rain is one of the most important atmospheric phenomena that is directly related to ecosystems and human lives. Numerous meteorological organizations operate weather radars to measure in-situ rainfall. This study performs very short-term prediction of rainfall distribution and intensity for up to 2.5 h over the Korean Peninsula experiencing various rain types, such as typhoon, stationary-front, and localized heavy rainfalls, using convolutional Long Short-Term Memory (ConvLSTM) networks and the constant altitude plan position indicator data provided by the Korean Meteorological Administration (KMA). The ConvLSTM-based prediction models were trained using 3522 cases of radar-based rainfall data from April to October in 2018 and 2019, as well as 1584 typhoon, stationary-front, and localized heavy rainfall events during August and September 2020, respectively. The rainfall presence prediction model showed a decrease in the critical success index (CSI) (0.8659 to 0.7266, 0.7366 to 0.4821, and 0.5302 to 0.0946 for typhoon, stationary-front, and localized heavy rainfalls, respectively) from 10 min to 2.5 h. The rainfall intensity prediction model showed an Heidke skill score of 0.4741 for light rain (0.1 to 3 mm/h) after 1 h. However, heavy and very heavy rainfall events were not predicted due to the lack of their training datasets and short lifetimes, which was supported by the relationship between the average rain event rate (for 150 min) and CSI index. Consequently, compared to KMA’s operational MAPLE model. The ConvLSTM-based models are effective in predicting rainfall type and its intensity over wide areas for a relatively long time.
... In another study, Ghoddousi et al. (2015) ranked weather conditions as the top 16 among 32 other factors influencing productivity. El-Rayes and Moselhi (2001) evaluated the impact of rainfall on productivity in the construction of highway projects and proposed a system to predict the impact. The hot climate has been indicated as one of the main factors influencing labor productivity in Bahrain, Oman and Nigeria (Jarkas, 2015;Jarkas et al., 2015;Muhammad et al., 2015). ...
Purpose
Climate change and global warming have increased concerns over the influence of weather on workers' health and productivity in construction projects. A significant number of studies can be found in the weather and productivity interplay area. The purpose of this paper is to review the recently published papers in this area to explore the trends of research and topics discussed and to determine knowledge gaps and directions for future research.
Design/methodology/approach
Recent papers published between 2014 and 2019 were synthesized, reviewed and analyzed using bibliometric and text mining analysis.
Findings
The results revealed the trends of publications, the main authors contributed to this area and countries that attracted most of the research papers. Based on the review, this study presented a taxonomy of studies consisting of seven clusters, namely productivity management, seasons, weather factors, participants' conditions, uniform and clothing, work time and health and safety.
Originality/value
This review paper sheds a light into the topics discussed in this area, the interrelationship between the topics and the significant topics that should be continued in the future. Global warming concerns necessitate the need for more studies in tropical countries and countries that are expected to expose to high temperatures and heat stress, which greatly impact labor productivity. The paper highlighted the need to understand how weather influences workers' psychological conditions and subsequently their productivity.
... For example, highway construction projects are so sensitive to rainfall that complete suspension of operations may occur as a result of saturated or unworkable soil and paving conditions (El-Rayes & Moselhi, 2001). This means that productivity will suffer unless management devises a method for compensating for it or at least mitigating its effects (Christian & Hachey, 1995). ...
The construction industry is a relatively busy one due to rapid urbanization in Bangladesh. Productivity is the common measure of performance in the construction industry. The aim of any construction organization must be to attain higher productivity since it can translate directly into cost savings and ultimately into profits (Hancher and AbdElkhalek, 1998). Bangladesh is one of the most susceptible nations due to climate change in the world. Its relatively insufficient land space for the large population have put tremendous pressures on the ecosystem, as it is the ninth most populous and twelfth most densely populated country in the world. In order to catch up the increased rate of urbanisation, the capital, Dhaka, underwent stark and rapid transformations in a short span of years. An influx in the real estate, construction and housing industry in the country acted as a response to this change. Dhaka tops the list of the most polluted cities in the world in the reports presented by the United Nations Population Fund (UNFPA). Green buildings are necessary particularly environments like that of Dhaka. A number of architects, builders and clients emphasize that smart, sustainable buildings are becoming inevitable. Construction works account for almost half of the material and energy consumption, one-sixth of fresh water consumption and a quarter of all wood garnered in the world, according to assessments by experts in this field. In project management, the success rate is presumed by efficiency involved in project completion and quality (Serrador and Turner, 2015). Dhaka, the capital of Bangladesh, has several infrastructural projects on-going as per Kazi Nasir, chief architect of Bangladesh. Project managers involved in these thrive to deploy green-construction, which is eco-conscious and environment friendly. While the drawings, safety, regulations and even weather conditions accomplished in desirable manner, there is undeniable gap in productivity. Projects are stalled due to incomplete planning and uncertain issues in management. Project delays, added expenses, sub-standard quality and even overall project failures can be directly linked to low productivity in projects (Nwagbogwu, 2011). This research will attempt to identify the gap and submit the findings.
... Among the common causes of project delays is the weather which is consistently rated as very frequent and harmful (AlSehaimi and Koskela, 2008). Weather can impact construction projects in multiple ways: by decreasing productivity and sometimes halting construction ( Rogalska et al., 2006); by ruining unprotected and exposed constructed elements (El-Rayes and Moselhi, 2001), by disrupting communications and/or blocking access to site locations. The impact of (adverse) weather is a common cause of delay leading to legal claims and economic losses in construction projects ( Ballesteros-Perez et al., 2018). ...
The construction industry is embedded with risky situations that affect construction projects and therefore requires systematic processes to achieve project objectives and ensure business sustainability. In achieving project and business objectives, contractors usually experiment many techniques and management practices in addressing construction pricing risk. The aim of this study is to examine critical risk factors in pricing of construction resources of SME construction firms. To achieve the aim of the study, a quantitative research method was adopted where questionnaire was administered to professionals (Quantity Surveyors) with D3K3 and D4K4 construction firms. The quantitative data was analyzed with factor analysis. The results of the analysis of the risk factors were grouped under three categorizations: fiscal risk factors, engineering and
environmental risk factors and human and socio-economic risk factors. It is suggested that pricing experts should consider these risks in the pricing in order to reduce unforeseen implications associated with the outcome. The implication of this study is that it will help pricing experts in safeguarding future cost implications as a result of the associated risk. This study critically considers the views of quantity surveyors in the construction industry, it is therefore recommended that further studies should take into consideration the views of other key stakeholders in the construction industry.
... On the other hand, other authors (e.g., Tucker & Rahilly, 1982 [19]; Koehn & Brown, 1985 [14]; Chan & Kumaraswamy, 1995 [6]; El-Rayes & Mosehli 2001 [9]; Wiliams, 2008 [21]; Odabasi, 2009 [15]) have explored the climatic factor giving rise to some predictive models with varying success. Nevertheless, we have not found any studies measuring the influence of all the seasonal factors in the construction directly. ...
The objectives in each construction process can be multiple. However, the constructions have to be carried out under some restrictions concerning price and terms. They constitute some strategic and interdependent goals. In other words, “time is money”. Several papers support that seasonal effects influence the execution rate of construction. Thus, most of them try to improve the forecasts by evaluating and joining them to the planning, although always measuring their influence indirectly. In this paper, we suggest a methodology to directly measure the influence of the seasonal factors as a whole over the earned value of construction. Additionally, we apply it to a certain case study regarding the subsidised housing of public promotion in the Castilla-La Mancha region (Spain). It is worth mentioning that our results are clarified: we have calculated the average monthly production for each month a year with respect to the annual monthly mean. Moreover, the differences regarding the average monthly production we have contributed are quite significant, and hence they have to be taken into account for each earned value forecast so that a project becomes reliable.
... Moselhi et al. (1997) developed a computer program based on a set of proposed equations to estimate reduced labor productivity and work stoppage. El-Rayes and Moselhi (2001) captured impacts of rainfall on the productivity of road construction projects through a step-by-step procedure based on historical data. Jang et al. (2008) proposed a method for applying expected schedule updates on Microsoft Project software based on the short-term weather condition forecast. ...
Purpose
Many construction projects are implemented in open-environment job sites and can be significantly affected by various weather conditions. Evaluating the overall impacts of the weather conditions on a project can assist project managers to prepare effectively. Nevertheless, methods measuring the overall adverse impacts of the job sites’ weather condition on the project performance are still missing. This study aims to address this gap.
Design/methodology/approach
In this investigation, a survey-based method was proposed to evaluate the overall impacts of the weather conditions on the construction project resources through a new indicator called job site weather index (JWI). The target survey population includes practitioners directly involved in the on-site construction operations.
Findings
The JWI suggests the direction of the resource change in new construction projects based on the weather condition. The method was implemented in the road construction projects of Iran and successfully applied to four sample cities. In this experiment, construction workers were identified as the most susceptible resources to the unfavorable weather conditions. Hot temperature above 50°C and cold temperature below −10°C were ranked as the most influential factors for the workers. The results achieved showed high accordance with the trends currently followed in the country.
Originality/value
This research was the first structured method for capturing impacts of weather conditions on the performance of construction resources in open environment construction projects. Implementation of the method in road construction projects of Iran revealed new results that have not been previously identified. The impacts of the company-specific factors on the final productivity rate, however, were not investigated in the research. Investigations accounting impacts of various company-specific factors on the final productivity rate are required.
... Hence, all the three countries under investigation were situated at the same geographical location and experienced similar tropical climate and construction processes. These factors contribute significantly to environmental and risk assessment of construction projects (El-Rayes and Moselhi, 2001). Furthermore, regarding waste management guidelines, all three countries have specific laws that govern the effective utilisation of material resources and possible reuse or recycle at the end of the material life cycle. ...
The construction sector is among the fastest growing sectors in Malaysia; it consumes a vast amount of natural resources and produces a massive volume of construction and demolition waste. The waste is collected in a decentralised manner by sub-contracted companies. It is challenging to obtain reliable information on the amount of construction waste generated, because it is hard to determine its exact quantity and composition. Therefore, this study proposes a quantitative construction waste estimation model for residential buildings according to available data collected from the Construction Industry Development Board, Malaysia. In the development of this model, a theoretical investigation of the construction procedure and the construction waste generation process was conducted. The waste generated rate was determined as 25.79 kg m⁻² for new residential constructions, which translates into about 553,406 t of anticipated waste annually.
... This frequent problem of project delays, considering a 'delay' here as not meeting the original completion date, has been researched under multiple perspectives: economic (Yates, 1998), social (Hamzah, Khoiry, Arshad, Tawil & Che Ani, 2011), legal (Keane & Caletka, 2008), analytical (Alkass, Mazerolle & Harris, 1996), programmatic (Braimah, 2014), etc., to cite just a few. Project delays have also been studied from all parties' perspectives too: contractor's (Mahamid, 2013), client's (El-Rayes & Moselhi, 2001), government's (Orangi, Palaneeswaran & Wilson, 2011), country's (Ogunlana, Promkuntong & Jearkjirm, 1996), suppliers' (Choi & Hartley, 1996), and workers' (Mahamid, 2013). ...
Many engineering projects fail to meet their planned completion dates in real practice. This a recurrent topic in the project management literature, with poor planning and controlling practices frequently cited among the most significant causes of delays. Unfortunately, hardly any attention has been paid to the fact that the classical scheduling techniques: Gantt chart, Critical Path Method (CPM), and Program Evaluation and Review Technique (PERT), may not be as fit for purpose as they seem. Arguably, because of their relative simplicity, these techniques are still almost the only ones taught nowadays in most introductory courses to scheduling in many engineering and management degrees. However, by utterly ignoring or inappropriately dealing with activity duration variability, these techniques provide optimistic completion dates, while suffering from other shortcomings. Through a series of simple case studies that can be developed with a few participants and common dice, a systematic critique of the classical scheduling techniques is offered. Discussion of the case studies results illustrate why limiting the contents of scheduling education and teaching can be detrimental, as the aforementioned classical scheduling techniques cannot not provide project managers with sufficient resources to effectively plan and control real projects.
... According to the literature, different weather factors can affect cost and productivity, and cause delay in construction projects [33,56]. El-Rayes and Moselhi [20] confirm that rainfall can cause a complete stoppage in highway construction. Koehn and Brown's [37] investigation suggests a clear relationship between overall construction performance and weather-related factors such as temperature and humidity. ...
This paper proposes a decision support (DS) framework that incorporates weather-related factors for the purpose of estimating the duration of projects. Inclement weather can have a serious effect on construction projects, particularly with regard to duration and costs. The weather has an impact on human resource productivity, supplier effectiveness and material damage which can, in turn, affect the duration of a construction project. The proposed five-module framework integrates weather variables, project performance variables and duration of project activities. This framework uses expert knowledge about the importance of weather variables, pairwise comparisons of weather variables with respect to different performance criteria, and similarly, pairwise comparisons of performance variables with respect to project activities. A model based on this framework, using multivariate statistical techniques and an analytical network process (ANP), is developed to estimate the duration of project activities, taking into account the impact of weather. The proposed model is illustrated with data from a construction project from Iran. Validation of the model is provided by comparing the actual duration of an activity with the estimated duration, using the proposed framework.
... McDonald (2000) examined weatherrelated delay claims for construction projects and how they can be resolved. El Rayes and Moselhi (2001) developed a decision support system for quantifying the impact of rainfall on the productivity and duration of highway construction operations. Moselhi and Khan (2012) identified, analysed, and ranked the parameters that affect job-site daily labour productivity to help job-site personnel in planning and comparing their daily targets and to fine-tune their resource allocations according to the daily situation. ...
Qatari construction projects frequently encounter significant delays.
One of the major causes of these delays is ignoring Qatar’s extreme weather conditions on labor productivity. This paper studies the impact of temperature, humidity, and wind on labor productivity in Qatar for four construction trades, namely, formwork, masonry, plaster, and ceramic tiles. These trades were chosen because they are time-consuming and commonly found in most construction projects. Weather and trade labor productivity data were recorded between July 2013 and February 2014. The results showed that weather conditions have a high impact on trade labor productivity. They also showed that the labor productivity in the summer can be as low as half of that in the winter. Linear regression models were developed to predict trade productivity on a given day of the year.
... Guo (2000) analyzed the productivity losses of network activities in highway construction project, based on the historical rainfall records and fuzzy-set techniques. El-Rayes and Moselhi (2001) estimated the impact of rainfall on highway construction productivity and duration, based on knowledge base acquired from experts and historical database. Thorpe and Karan (2008) predicted the project schedule delay by using an experimental probability classification of weather condition, based on CPM network technique. ...
Effective construction scheme planning is critical for schedule management, but heavy rain can affect construction processes. In previous studies, stochastic rainfall characteristics are often ignored, and their impact on macro- and microconstruction states are not depicted comprehensively. This research presents a construction simulation model to design reasonable construction schemes considering impact of stochastic rainfall. First, a rainfall model suitable for areas with heavy rainfall and uneven seasonal rainfall distribution is built. Then, multiaspect indicators are defined to intuitively quantify rainfall impact. Two case studies are conducted to evaluate applicability of the proposed method. Results demonstrate that the developed rainfall model aligns closely with observed data. Simulation findings reveal that if stochastic rainfall characteristics are ignored, the schedule and queuing probability of trucks will be underestimated, while machinery utilization will be overestimated. This research provides an effective simulation tool for determining adaptive measures to mitigate impacts of rainfall events.
... • Location: It is paramount to understand the location dynamic of a project and the following should be considered, viz. interference with existing site, weather conditions, remoteness of location and experience in country ( Bosch-Rekveldt et al. 2011;El-Rayes & Moselhi 2001;Floricel et al. 2016;Nguyen et al. 2015;Sohi et al. 2016;Yang, Huang & Hsu 2014). • Market conditions: Market conditions play internal and external influencing roles in projects. ...
Background: Information communication and technology (ICT) projects are different from other projects, such as construction, and require a new perspective to determine their true nature. The lacklustre state of ICT projects has plagued researchers and practitioners for decades as they are yet to understand why ICT projects do not perform. Literature places significant emphasis on success criteria and success factors for determining project success, but this is a unilateral view as the level of complexity involved is underestimated. ICT projects, however, are multifaceted as there are a number of dimensions that influence the management and outcome of a project.
Objectives: This article aimed to illuminate how the dimensions are interdependent and interconnected through the construction of a conceptual model of ICT project complexity.
Methods: Content analysis was used to identify and understand the various dimensions and facilitated construction of the model.
Results: The article identified five dimensions that affect ICT projects, viz. project success, project lifecycle, project complexity, project types and project methods. Each dimension was analysed to understand the key constructs and elements that need to be considered. The dimensions were mapped in a multidimensional model.
Conclusion: The multidimensional model of ICT project complexity can be used by ICT project managers to more effectively manage projects as they are provided with a greater understanding of ICT project influences.
... Activity duration relates with a variety of factors, which are not all easily modelled and analysed. Weather is a major factor to affect periodicity in road construction, but which is not included in traditional construction simulation researches until El-Rayes and Moselhi [2]. ...
... As a result, rescheduling should repeatedly be done due to the ambiguity and imprecise data. Most of scholars focused on developing a real fuzzy model based only on one factor like as the rainfall, in order to assess the delay in highway construction (El-Rayes and Moselhi 2001;Guo 2000;Pan, Hadipriono and Whitlatch 2005). This paper develops a fuzzy logic model for forecasting and determining the delay encounters highway projects. ...
Performance of highway construction is sensitive to surrounding unforeseen factors. Rainfall, labor experience and efficiency of equipment are such examples, and therefore, quantifying their impact is essential in providing a realistic schedule. Thus, when a parameter is expressed in linguistic rather than mathematical terms, using Fuzzy gives feasibility in converting linguistic variables into mathematical measures. In this paper, a Fuzzy model is developed for quantifying delay, which influence on overall project performance. The output of this paper results in the value of delay depending on rainfall, labor, and efficiency of equipment factors, which helps consequently scheduler for giving the right decision, as well as planning a proper schedule to reality. Therefore, this value plays an important role in reducing risk throughout scheduling. For instance, it decreases the gap between actual and the planned schedule. This paper is a part from the Master thesis, which was done by the last author and supervised by the first three authors
This research investigated the impact of extreme weather on construction projects in Koronadal City. This study aimed to (1) identify the specific types of extreme weather events affecting construction projects; (2) measure the perceived level of impact of extreme weather on construction project timelines, budgetary allocations, labor productivity, equipment performance, and the overall project quality; (3) identify the potential health and safety hazards that might be encountered by individuals in the construction industry; and (4) measure the perceived level of effectiveness of the existing resilience measures employed by construction projects in Koronadal City to mitigate the adverse impact of extreme weather. Data were gathered using survey questionnaires from various respondents, including engineers and construction workers. A survey involving 177 respondents identified frequent weather-related challenges, with heat waves being the most prevalent, followed by heavy rainfall and less frequent occurrences of floods, tropical cyclones, and tornadoes. The study also explored the impact of extreme weather on the health and safety of construction personnel, highlighting issues such as physical strain, heat-related illnesses, and increased risks of accidents due to adverse weather. The findings indicate significant disruptions to project timelines and financial planning, with a considerable majority reporting that extreme weather necessitates project management and budgeting adjustments. Furthermore, the study reveals the effectiveness of current resilience measures, including providing adequate hydration and regular breaks in shaded areas and utilization of adequate rest breaks, rotating tasks, and employee wellness programs. This paper underscores the urgent need for enhanced adaptive measures and more efficient risk management strategies to ensure the safety and effectiveness of construction practices in regions vulnerable to extreme weather.
As chuvas causam impactos significativos na execução de obras, especialmente terraplanagem e pavimentação. Cronogramas que não consideram esses impactos levam ao não cumprimento do prazo, aumento dos custos e redução da qualidade das obras. Diante do exposto, este artigo objetiva determinar a improdutividade em obras de pavimentação e terraplenagem na cidade de Aracaju/SE em virtude das chuvas. Inicialmente foram obtidos dados de precipitação de chuvas em Aracaju/SE. Em seguida, realizou-se o tratamento dos dados para gerar o fator de improdutividade de cada mês. Posteriormente, foram determinados os dias úteis totais de cada mês e aplicando o fator de produtividade calculado, foram estimados os dias úteis trabalháveis e improdutivos. Os resultados mostraram que o período de Abril a Julho não é apropriado para se executar obras de grande afetação pelas chuvas, visto que, há muitos dias improdutivos por decorrência dos eventos de precipitação. Conclui-se que: a) O regime pluviométrico de Aracaju/SE afeta consideravelmente a produtividade de obras de pavimentação e terraplenagem; b) É indispensável conhecer os impactos gerados pelas chuvas, para que se possa realizar um planejamento adequado; c) As improdutividades decorrentes das chuvas devem ser consideradas ainda na fase de planejamento, visando assim, atenuar seu impacto no cronograma físico financeiro da obra.
Purpose: Climate variability in the South-South, Nigeria is a significant concern due to the region's vulnerability to extreme weather events such as heavy rainfall, flooding, and high temperatures. The region, being prone to extreme weather events, is vulnerable to disruption of construction activities and delayed project completion. The motivation of this study is to determine the impact of climate variability on construction project activities in the execution phase in the study area. Design/methodology/approach: This study assessed the drivers of climate variability in the study area, the extent of the impact of climate variability on construction activities, and determined the critical construction activities impacted by climate variability. Questionnaire survey was administered on proportionately stratified random sample of construction professionals in the study area. The derived data were subjected to both descriptive and statistical analyses using Mean Score, Relative Extent of Impact, and inter-rater agreement to spot the critical construction activities impacted by climate variability. Kendall's Concordance Coefficient was used to test the study's hypotheses. Findings: Findings revealed that gas flaring from oil companies, solar radiation, topography, and deforestation are the highest contributors to climate variability in the study area, as perceived by the respondents. Excavation of septic tank and soak-away pit; laterite filling to make up level, and placement of in-situ concrete in foundation footing, ranked in the first three positions as being impacted by rainfall. Excavation of trench for foundation; plain in-situ concrete in floor bed as oversite; and application of paint on external wall ranked in the first three positions as being impacted by temperature. Kendall's coefficients of concordance (W) were 0.89, 0.91, 0.73, and 0.86 for rainfall, temperature, humidity and wind speed respectively, revealing either substantial or perfect agreement among the respondents about extent of impact of climate variability on construction activities. Research limitations/Implications: The limitations include the use of three States to represent South-South region and the construction processes examined are limited to Building construction project. The contribution to knowledge is that this study established the critical construction activities prone to impact of climate variability in the execution phase. Practical implications: Manages of construction sites should plan the critical construction activities prone to impact of climate variability as derived by this study against catastrophic impact. Originality/value: The study revealed that rainfall and temperature significantly impact construction project activities in the study area. Inversely, no construction activity is found to be significantly impacted by humidity and wind.
Roller compacted concrete (RCC) is a kind of dry concrete widely used in the construction of large dams. As the weakest plane of the structure, the interlayer of the RCC dam is easy to deteriorate under the action of hydraulic shear load, geological action and environmental influence. Therefore, in this study, in combination with actual engineering, in-situ tests were carried out to study the shear properties of RCC interlayers under different cementing material treatments, different surface roughness, different exposure time and different stress. In addition, the failure modes were classified and analyzed, and the factors affecting the angle and depth of the plane undulation in the failed surface of RCC were summarized. The result shows that the shear strength of the RCC interlayer increases with the increase of normal stress. The increase of surface roughness results in better interlayer bonding and higher shear strength. After mortar treatment, the shear strength, cohesion and friction angle of the RCC layers are higher than those of the mortar treatment. The strength parameters of the RCC layer treated with cementing material are improved to a certain extent compared with that of the untreated layer. With the increase of layer exposure time, the interlayer strength parameters decreased gradually. The change of cementation between layers and the bite force of aggregate under different conditions is an important reason for the change of mechanical properties between layers of RCC. The experimental results are expected to enhance the understanding of the construction of hydraulic dams.
Dengan dicanangkannya percepatan pembangunan infrastruktur yang antara lain jugamencakup pembangunan 1600 km jalan tol dalam 5 tahun kedepan, pemerintah sudahmelakukan perombakan pada regulasi yang mempermudah untuk berinvestasi bisnis jalan tolyang bankable dengan ditetapkannya Undang-Undang No. 38 tahun 2004 tentang Jalan danPeraturan Pemerintah No. 15 tahun 2005 tentang Jalan Tol.Konsep yang mendasari jalan tol adalah suatu konsep pendanaan dimana dana pembangunanjalan tol sepenuhnya diperoleh dari pemakai jalan tol melalui pengenaan tarif tol. Sedangkaninvestor dibantu lembaga-lembaga pendanaan dalam hal ini berfungsi sebagai “jembatan†agarjalan tol yang bersangkutan dapat diwujudkan dan menghasilkan pendapatan. Industri jalan tolmerupakan proyek yang sangat dipengaruhi risiko dan ketidakpastian dimana timbulnya risikodan ketidakpastian akan mempengaruhi investor merencanakan investasi proyek jalan tol.Penelitian ini dilakukan untuk mendapatkan faktor-faktor utama dari sekian banyak faktor risikoyang mempengaruhi risk response planning investor jalan tol untuk memutuskan berinvestasijalan tol di Indonesia.Setelah melakukan pengujian data maka hasil penelitian didapat bahwa faktor internal lebihdominan dari pada faktor eksternal, dimana prioritas faktor berdasarkan kriteria yaitu identifikasirisiko dan risk attitute memberikan kontribusi hasil yang signifikan. Sedangkan urutan prioritasfaktor berdasarkan subkritera adalah; variabel penentuan besaran tarif, perkiraan biayakonstruksi, operasi, dan pemeliharaan, perkiraan volume lalu lintas, tingkat pengembalianinvestasi, masa konsesi, kematangan dalam mengambil keputusan, profesionalitas sikap, danketerlambatan penyelesaian proyek.
Bauablaufplänen kommt bei der Realisierung von Bauprojekten eine zentrale Rolle zu. Sie dienen der Koordination von Schnittstellen und bilden für die am Projekt Beteiligten die Grundlage für ihre individuelle Planung. Eine verlässliche Terminplanung ist daher von großer Bedeutung, tatsächlich sind aber gerade Bauablaufpläne für ihre Unzuverlässigkeit bekannt. Aufgrund der langen Vorlaufzeiten bei der Planung von Bauprojekten sind zum Zeitpunkt der Planung viele Informationen nur als Schätzwerte bekannt. Auf der Grundlage dieser geschätzten und damit mit Unsicherheiten behafteten Daten werden im Bauwesen deterministische Terminpläne erstellt. Kommt es während der Realisierung zu Diskrepanzen zwischen Schätzungen und Realität, erfordert dies die Anpassung der Pläne. Aufgrund zahlreicher Abhängigkeiten zwischen den geplanten Aktivitäten können einzelne Planänderungen vielfältige weitere Änderungen und Anpassungen nach sich ziehen und damit einen reibungslosen Projektablauf gefährden. In dieser Arbeit wird ein Vorgehen entwickelt, welches Bauablaufpläne erzeugt, die im Rahmen der durch das Projekt definierten Abhängigkeiten und Randbedingungen in der Lage sind, Änderungen möglichst gut zu absorbieren. Solche Pläne, die bei auftretenden Änderungen vergleichsweise geringe Anpassungen des Terminplans erfordern, werden hier als robust bezeichnet. Ausgehend von Verfahren der Projektplanung und Methoden zur Berücksichtigung von Unsicherheiten werden deterministische Terminpläne bezüglich ihres Verhaltens bei eintretenden Änderungen betrachtet. Hierfür werden zunächst mögliche Unsicherheiten als Ursachen für Änderungen benannt und mathematisch abgebildet. Damit kann das Verhalten von Abläufen für mögliche Änderungen betrachtet werden, indem die durch Änderungen erzwungenen angepassten Terminpläne simuliert werden. Für diese Monte-Carlo-Simulationen der angepassten Terminpläne wird sichergestellt, dass die angepassten Terminpläne logische Weiterentwicklungen des deterministischen Terminplans darstellen. Auf der Grundlage dieser Untersuchungen wird ein stochastisches Maß zur Quantifizierung der Robustheit erarbeitet, welches die Fähigkeit eines Planes, Änderungen zu absorbieren, beschreibt. Damit ist es möglich, Terminpläne bezüglich ihrer Robustheit zu vergleichen. Das entwickelte Verfahren zur Quantifizierung der Robustheit wird in einem Optimierungsverfahren auf Basis Genetischer Algorithmen angewendet, um gezielt robuste Terminpläne zu erzeugen. An Beispielen werden die Methoden demonstriert und ihre Wirksamkeit nachgewiesen.
In most work sites, it is a priority to keep the work going well and to avoid unforeseen incidents. Fluctuations in weather conditions are one of the factors affecting the continuity of work in construction projects. Indeed, for example, the temperature is important in concrete and asphalt works, and wind speed is important in lifting and high construction works. Therefore, taking the appropriate decision, starting and completing the work, is very important to maintain the quality of the project. This research aims to demonstrate the reliability of short-term decision-making through data taken from the weather site five days before the time to work. The data was collected for a month, five days before the intended day and on the same day, day and night, for different weather factors by weather location such as temperature, humidity, possibility of rain, Uv index, wind speed. By analyzing the data, it was found that there was little difference in those predictors of all the factors recorded. To conclude at the end of the study that it is possible to rely on the decision-making on the weather location in small and medium projects, but in large and sensitive projects, they need to rely on more accurate data than relying on weather location data.
Executed outdoors in high-wind areas, adverse weather conditions represent a significant risk to onshore wind farm construction activities. While methods for considering historical weather data during pre-construction scheduling are available, approaches capable of quantitatively assessing how short-term weather fluctuations may impact upcoming construction activities have yet to be developed. This study is proposing a hybrid simulation-based approach that uses short-term precipitation, wind speed, and temperature forecasts together with planned and as-built activity durations to develop lookahead (e.g., upcoming 14-day) schedules for improved project planning and control. Functionality and applicability of the method was demonstrated on a case study of a 40 MW onshore wind project, and the method was validated using event validity, face validation, and sensitivity analysis. As expected, favorable weather conditions experienced during the tested lookahead periods resulted in a negligible impact (less than 10% reduction) on the productivity of weather-sensitive activities, which translated into a project delay of one day. The responsiveness of the framework was confirmed through sensitivity analysis, which demonstrated a 50% reduction in productivity resulting from poor weather conditions. The ability of the method to provide decision-support not currently offered by commercially-available scheduling systems was confirmed by subject experts, who endorsed the ability of the method to enhance lookahead scheduling and to facilitate the monitoring and control of weather impact uncertainty on project durations.
Formwork is considered as important element of construction projects like in traditional reinforced concrete infrastructure projects. It is labor-intensive work that requires highly skilled workers such as carpenters, bar benders, etc., to execute the work more accurately and efficiently. In view of the fact that it is difficult to find high-skilled workers for formwork process and hence it is important to find the ways or methods of formwork construction that is less labor dependent or in other words methods that are highly productive with minimum number of workers. The quality of formwork exerts a direct influence on the surface of concrete and on its dimensions. Since reinforced concrete work is involved in majority of the buildings, the level of workmanship of the construction project can be identified by seeing the quality of formwork. In order to improve the productivity of the formwork process and its quality then it is necessary to improve its working methodology by identifying the bottlenecks using scientific management. And as we very well know that money is always the center of discussion in our construction projects. To complete the project within its expected, designed cost of the project is one of the major requirements of the project to become a successful project. That’s why the topic ‘Productivity analysis in shuttering for Sewer Treatment Plant Project’ is a great tool to analyze the shortcomings in the present methodology of formwork erection and to mechanize a highly effective model for formwork and this can be achieved by the productivity analysis.
In construction field work, weather events are a key risk factor in planning. Such events can impact productivity and, ultimately, project progress. Unforeseen weather situations can lead to delays and budget overruns. Recent efforts have been made in the construction industry to collect weather data at variously located weather stations through sensor technology. These data provide a foundation for reliable weather information. Monitoring the weather situation in a given area still presents challenges, given that weather stations are located great distances apart. A scientific method is desired to make use of limited collected weather data in order to reasonably estimate detailed weather conditions for construction purposes. In this research, a simulation-based, mathematical model has been developed using kriging interpolation method to estimate weather situations and their corresponding impacts on construction projects. Weather data and geographical information are used as inputs for the proposed model. The weather situation in the project area is simulated based on historical data, and its impacts on project planning are analyzed using the proposed model. Based on this methodology, a case study on winter road maintenance is developed and presented.
Production systems strive to achieve zero-inventory as a mechanism of waste minimization, which requires that the demand and supply of products are synchronized in time and volume. The effects of weather condition on construction projects has implications for site productivity, and consequently the demand for building materials, particularly in wet trades where cement is the primary constituent. The study explores and spotlights the multi-dimensional influence of weather conditions on the consumption of cement induced by the supply/demand gap. Using multiple regression analysis, the study provides statistical evidence establishing causality between weather and the trend in the consumption of cement. Data on the consumption of cement on hundred randomly selected construction sites within Port Harcourt, as well as meteorological data for a period of 12 months, were collated to serve as quantifiable attributes of the study variables. The outcome of the study was the development of a regression model statistically depicting the demand for cement as a function of meteorological indices. The study outcome can thus serve as part of a more comprehensive decision support system, necessary to minimize waste and identify potential inefficiencies in the production and distribution channels of cement in Port Harcourt.
In highway projects, major losses can occur when the estimated contract time is unrealistically longer or shorter than the actual time needed. This study presents a comprehensive review of the different contract time determination systems developed for various Departments of Transportation (DOTs) in the U.S.A. Also, the study addresses some of the main factors that can affect the activities’ production rates. The study contributes to the body of knowledge by updating the literature about the contract time determination systems used by different DOTs. A survey was designed and sent to the 52 DOTs in the U.S.A. to verify and collect additional information. The results provide further insights into the contract time determination methods used by DOTs and other factors that might affect the production rates in highway construction. This paper should prove useful for future studies focusing on the contract time determination for highway projects.
Purpose
This study investigates the level of variance in the real time demand for bagged cement, induced in response to the climatic sequence of the humid tropics, to support best practice calls for a weather-responsive supply chain strategy.
Design/methodology/approach
Data on the consumption of cement and site works for 100 ongoing building construction sites were gathered for a period of 12 months. The variance partitioning capabilities of the Ordinary Least Squares and Hierarchical Linear Modelling forms of regression analysis are comparatively used to evaluate the sensitivity of cement demand to the meteorological profile of wet-humid climate
Findings
The study outcome provides statistical evidence demonstrating that the meteorological profile of wet-humid climate induces a significantly high percentage of the variance in the real-time demand for bagged cement on construction sites. However, nested within this variance, are the fixed effects of the cement footprint of the building architecture inherent in the locality. Particularly, positive changes to reduce the wet trade composition of buildings or compensating changes in technological bias, are necessary to combat weather interference in the humid tropics.
Research limitations/implications
The findings are exploratory, and not for the purposes of holistically forecasting cement demand, and can therefore only form part of a more comprehensive decision support system, bespoke to the study area.
Practical implications
The study outcome provides a back-end view to climatic adaptation in wet humid settings, making a compelling case for localized climate-risk adaptive supply chain strategies and policies geared towards sustainability in cement usage.
Originality/value
The study delineates the confounding impact of weather, distinct from local building architecture and technological bias, thus creating a methodological platform for replication and comparative productivity studies in diverse geographical areas.
Purpose: This study investigates the level of variance in the real time demand for bagged cement, induced in response to the climatic sequence of the humid tropics, to support best practice calls for a weather-responsive supply chain strategy. Design/methodology/approach: Data on the consumption of cement and site works for 100 ongoing building construction sites were gathered for a period of 12 months. The variance partitioning capabilities of the Ordinary Least Squares and Hierarchical Linear Modelling forms of regression analysis are comparatively used to evaluate the sensitivity of cement demand to the meteorological profile of wet-humid climate. Findings: The study outcome provides statistical evidence demonstrating that the meteorological profile of wet-humid climate induces a significantly high percentage of the variance in the real-time demand for bagged cement on construction sites. However, nested within this variance, are the fixed effects of the cement footprint of the building architecture inherent in the locality. Particularly, positive changes to reduce the wet trade composition of buildings or compensating changes in technological bias, are necessary to combat weather interference in the humid tropics. Research limitations/implications: The findings are exploratory, and not for the purposes of holistically forecasting cement demand and can therefore only form part of a more comprehensive decision support system, bespoke to the study area. Practical implications: The study outcome provides a back-end view to climatic adaptation in wet humid settings, making a compelling case for localized climate-risk adaptive supply chain strategies and policies geared towards sustainability in cement usage. Originality/Value: The study delineates the confounding impact of weather, distinct from local building architecture and technological bias, thus creating a methodological platform for replication and comparative productivity studies in diverse geographical areas.
Wet conditions are unpredictable factors that nonetheless, are estimated and incorporated onto a long term project schedule. Effective scheduling does mitigate the productivity of a job-site, however, when you factor in unforeseen wet conditions, it could result in schedule delays, material damages, and a discontent client. This paper presents an analysis on how job-sites adapted or were affected by the unpredicted amount of rain received in San Luis Obispo County. The initial findings, based on qualitative attitudinal research, are presented to show if schedules accounted for the amount of rain received, if their schedules were delayed, if material was damaged on the job-site, if they missed out on financial opportunities, and if they adapted to unforeseen wet conditions. Further discussions, based on qualitative exploratory research, are presented to identify strategies used by general contractors who mitigated the delays associated with rain days. The survey results indicate general contractors in San Luis Obispo County struggled to adapt during unforeseen wet conditions. The interview results analyzed common or successful strategies used by five different general contractors. With the identification of proper strategies, one could improve the productivity on the job-site during unforeseen wet conditions.
The study analyses the relationship between the growth of the construction industry and economic shocks in Ghana over the 50-year period from 1968 to 2017 using an autoregressive modelling scheme that incorporates several economic shocks as separate independent variables. The independent variables used in the model included one positive economic shock and five negative shock variables. The positive shock variable was the sharply increased government expenditures on construction activities in selected years that allowed the government to host international events in Ghana within a period of two years. The five adverse economic shocks included in the model were political instability related to military coups, exchange rate depreciation of the local currency, Ghana cedi, with respect to the United States dollar, the average yearly temperature, aggregate electricity energy production shortfall related to a severe El Nino weather phenomenon, and incidence of extreme rainfall. The results of the analysis indicated that the most important factor influencing the growth of the construction industry in Ghana over the 50-year study period was political instability. Beyond political instability, the next most important factor was the purposely-driven sharp increases in government expenditures on construction activities for selected years that allowed the country to host international events in the country. The other significant economic shocks were the exchange rate depreciation, average temperatures, and electricity energy production shortfall; all three factors adversely affected the growth of the construction industry. The results of our study are generally consistent with those obtained from the literature concerning the positive and negative effects of economic shocks on the construction industry.
One of the most controversial areas in construction claims is the quantification of lost labor productivity. Although labor hours and installed quantities can be tracked, lost productivity is very difficult to track contemporaneously. Furthermore, labor productivity is susceptible to many factors, some of which are within the contractor's control and some which are not. As a result, entitlement, causation, and credible quantification for loss of productivity claims are difficult to establish and many methods of quantification are subject to challenge with respect to validity and applicability to particular cases. This paper will review the methods to quantify lost labor productivity used in the US construction industry, along with relevant case law, and discuss the practical considerations in selecting the appropriate method for a specific case. This paper will also discuss the challenges that result from different legal and cultural backgrounds and provide caveats when quantifying lost productivity in the context of international claims.
This paper proposes a decision support (DS) framework that incorporates weather-related factors for the purpose of estimating the duration of projects. Inclement weather can have a serious effect on construction projects, particularly with regard to duration and costs. The weather has an impact on human resource productivity, supplier effectiveness and material damage which can, in turn, affect the duration of a construction project. The proposed five-module framework integrates weather variables, project performance variables and duration of project activities. This framework uses expert knowledge about the importance of weather variables, pairwise comparisons of weather variables with respect to different performance criteria, and similarly, pairwise comparisons of performance variables with respect to project activities. A model based on this framework, using multivariate statistical techniques and an analytical network process (ANP), is developed to estimate the duration of project activities, taking into account the impact of weather. The proposed model is illustrated with data from a construction project from Iran. Validation of the model is provided by comparing the actual duration of an activity with the estimated duration, using the proposed framework
Weather plays a pivotal role in almost every construction project. Historical observations of weather conditions in an area are closely used during project design, pre-construction planning, and construction stages. During the last five years there has been a steady increase in the number of paid weather services that claim to provide more accurate weather data as compared to the free weather services. The aim of this research study is to compare the reliability and accuracy of paid weather services versus the free ones. Weather data (high and low temperatures, precipitation, and wind speed) were recorded over the course of 90 calendar days from two different weather services namely the National Weather Service (Free) and a private site specific weather service (Paid). The weather forecast data of both services were statistically analyzed and compared against the actual observed conditions. The results indicated no significant statistical differences between the two weather services. In addition, both services fell short in predicting the accurate weather conditions beforehand. The findings of this study will help construction managers to decide whether or not to use a paid site-specific weather service as a decision-making tool for a specific project.
Qatari construction projects frequently encounter significant delays.
One of the major causes of these delays is ignoring Qatar’s extreme weather conditions on labour productivity. This paper studies the impact of temperature, humidity, and wind on labour productivity in Qatar for four construction trades, namely, formwork, masonry, plaster, and ceramic tiles. These trades were chosen because they are time-consuming and commonly found in most construction projects. Weather and trade labour productivity data were recorded between July 2013 and February 2014. The results showed that weather
conditions have a high impact on trade labour productivity. They also showed that the labour productivity in the summer can be as low as half of that in the winter. Linear regression models were developed to predict trade productivity on a given day of the year.
Construction noise control (CNC) is the process of identifying potential noise emissions and establishing noise-abatement plans to mitigate pollution impacts, a process that requires interdisciplinary knowledge and project-specific information. This study introduces an ontological approach to structure all known information on noise control with regard to construction operations, aiming to improve access to knowledge relating to CNC planning. More importantly, information that can be used to analyze the potential influences of noise-abatement measures in terms of costs, schedules, and technical rules is also considered in order to facilitate integrated decision making by outlining various outcomes for each alternative. Literature and expert reviews were conducted to identify the critical concepts and interrelationships between the method statement and the noise-control plan. Consequently, an ontology-based semantic model for CNC planning is presented as a modeling framework, which could be further enriched with more operational knowledge considering the specific purpose of an individual CNC plan. The prototype is applied to excavation construction to illustrate how CNC knowledge can be stored and reused through ontological and semantic web techniques.
The influence of unforeseen, extreme weather in construction works usually impacts productivity, causes significant project delays and constitutes a frequent source of contractor’s claims. However, construction practitioners cannot count on sound methods for mediating when weather-related claims arise, nor harnessing the influence of weather variability in construction projects. Building on the few most recent quantitative studies identifying those key weather agents and levels of intensity that affect some standard building construction activities, a new stochastic model that processes and replicates the spatio-temporal variability of combined weather variables is proposed. This model can help anticipate weather-related project duration variability; improving construction productivity by selecting the best project start date; and objectively evaluating weather-related claims. A two-building construction case study using different Spanish locations is used to demonstrate the model. The results showed that ignoring the influence of weather can lead to an extension of 5-20% longer project duration compared to planned.
The climatic conditions of a region are one of the issues that must be kept in mind while designing any facade related to civil construction. Front view of the building is such a part of the design for any building which is indeed the very first part of the building which remain in direct contact with the outside world. The exterior design of the building is the most important part of the climatic design. The Tehran initiates with the foothills area so by using design in harmony with the region's climate more savings can be achieved. In this regard, first, you must correctly identify the area followed by suitable proposals in order to design inconsistent with the climate of the area. Present paper is based on the descriptive type and analysis of library stuffs.
Wind energy is one of the most promising renewable energy and wind farm is globally constructed for sustainable development. However, wind could produce adverse effects on some wind-sensitive tasks of wind turbine construction projects. Due to limited understanding of how wind may influence productivity in wind turbine construction project, this research presents a fuzzy duration forecast model for wind turbine construction project subject to the impact of wind uncertainty. Through the use of Beaufort scale, professional expertise, and fuzzy membership functions, the productivity loss (PL) subject to various Beaufort scale of wind can be analyzed. With historical wind speed data incorporated, the duration can be simulated and forecasted by the model. Besides, the practicality of the model is demonstrated by an actual wind turbine construction project. The findings from this research are very useful in allocating schedule risk for wind turbine construction projects where wind uncertainty arises.
Mason productivity is determined by architectural design, contractor efficiency, mason skill, and weather. Thermal stress in humans is affected by the balance between metabolism and evaporation, convection, and radiation. These heat transfers are affected by environmental conditions of temperature, humidity, air movement, and radiation. Correlations between all thermal stress variables and labor productivity have not been established for construction craftsmen. However, relationships between mason productivity and temperature and humidity have been established. Meteorological data from 73 United States weather stations have been used to determine geographical variations in mason productivity as affected by these climatic variables.
The results obtained from a nationwide survey of architects, engineers, and contractors into the causes of construction industry delays are presented. Seventeen items were examined: weather; labor supply; material shortage; equipment failure; finances; manufactured items; construction mistakes; design changes; foundation conditions; permits; shop drawings; sample approvals; building codes; subcontractors; contracts; jurisdictional disputes; and inspections. Those found to be most important are described in an effort to suggest ways to reduce costly delays.
The results of a study designed to determine the cost of working during the winter months in a typical northern state are presented. The data indicates that contractors perceive an 11.3 percent increase in costs due to cold weather work. This additional expense is approximately equal to the cost, neglecting the effect of inflation and interest, of delaying the work until the following summer months. In addition, the financial impact of winter construction accidents was found to be roughly in the same range as that of the benefits paid to unemployed construction workers.
Past studies of masonry-labor Productivity fail to accurately identify the factors that most affect masonry productivity and to quantify the factors' effects. This paper describes a methodology to identify and quantify the project-related factors that significantly affect masonry productivity. Standardized data-collection techniques are used to collect and consolidate data from 11 central Pennsylvania masonry projects. Exploratory analyses are performed to determine which most affect productivity. The factors identified are the work type, building element, construction methods, design requirements, and weather. More detailed analyses indicate that: (1) Data from multiple projects can be consolidated to obtain statistically valid results; (2) repetitive designs can effect a 30% improvement in productivity; (3) designs that require extensive layout and cutting can negatively affect productivity by as much as 40%; and (4) the effects of weather on masonry productivity are not well understood and deserve additional research.
Research on uncertainty in construction has emphasized the importance of incorporating uncertainty factors in project-cost and time forecasts. However, little attention has been paid to identification and quantification of the specific risks. The present paper focuses on an assessment of the effect of uncertainty on the outcomes of planning. The effect of eight situational variables is evaluated by measuring the schedule and man-hour variances of the project, as well as the extent of usage of plans. The variables examined are number of subcontractors, number of trades, objectives rigidity, percentage completion of design, past construction experience, predictability of weather, availability of labor, and attitudes toward planning. The findings show which of the various situations affect any one planning measure, as well the extent of such influence. The paper concludes with an analysis of the financial implications of the prevailing practice of overlapping design and construction.
The results of an investigation designed to determine the relationship between overall construction productivity, and temperature and humidity are presented. Data from the following activities or crafts, or both, were employed: excavation (manual), erection, masonry, electrical, carpentry, laborers, and excavation (equipment). Two nonlinear equations were determined, one for cold or cool weather (R2 = 0.62) and another for hot or warm weather (R2 = 0.64). The overall findings indicate that below –10° F and above 110° F it is difficult to achieve efficient construction operations. In addition to productivity data, the health hazards, possible preventive measures, and acclimatization of workers to severe environments are examined.
Weather delay time extensions.” Hwy. and Heavy Constr
- S Isom
Isom, S. (1995). ''Weather delay time extensions.'' Hwy. and Heavy Constr., July 1985, 41.
Rains wreck summer schedules The McGraw-Hill Construction Weekly
- R Korman
- S W Setzer
- M B Powers
Korman, R., Setzer, S. W., and Powers, M. B. (1992). ''Rains wreck summer schedules.'' Engrg. News Rec., The McGraw-Hill Construction Weekly, August 31, 1992, 6–7.
Weather impact on construction productivity
- T Fadaka
Fadaka, T. (1999). ''Weather impact on construction productivity.'' Major Technical Report, Dept. of Build., Civ. and Envir. Engrg., Concordia Univ., Montreal. Grimm, C. T., and Wagner, N. K. (1974). ''Weather effects on mason productivity.'' J. Constr. Div., ASCE, 100(3), 319–335.
Rains wreck summer schedules.” Engrg. News Rec. The McGraw-Hill Construction Weekly
- R Korman
- S W Setzer
- M B Powers
Estimating weather impact on duration of construction activities.” Can
- O Moselhi
- D Gong
- K El-Rayes