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Advanced planning model of formwork layout for productivity improvement in high-rise building construction
Abstract
The recent trend toward irregular shapes in high-rise building construction makes planning formwork layouts a more complex and laborious task that has been mainly conducted by a heuristic method based on the intuitive judgment of formwork engineers. This study suggests a new planning approach integrated with practical software for formwork layout that is optimized for deploying formwork panels around structural obstacles while minimizing manual efforts. The proposed approach uses a harmony search algorithm (HSA); it has demonstrated improvement in work efficiency of formwork and has reduced formwork costs by minimizing both the use of nonstandard panels and the total number of panels. A case verification showed that the proposed planning method provided a 56% decrease in nonstandard panel-covered area with 14.1% lower cost than the previous heuristic approach by a formwork expert. Moreover, the results indicated that HSA was more efficient than the genetic algorithm (GA) in layout planning of formwork panels. The advanced planning method will support formwork engineers and will also contribute to increasing formwork productivity.
... A report on lighting and color schemes is accessible by non-professionals responsible for improving these strategies [17]. The layout of the previous building must be considered before planning for an extension of another [18]. Wind not only affects construction projects but also has the potential to impact the environment regarding the development of energy [19]. ...
... This process allows the smooth running. These findings are in line with preliminary studies by [18,27,28]. ...
... The variables of project contours or geographical conditions, relative humidity, wind, color scheme, and pollution have a negligible effect on worker productivity. These findings are not in line with preliminary studies [17,18,22,24,26]. ...
... Recently, studies have been conducted with the objective of applying various algorithms and advanced systems for designing formwork owing to the complexity of the formwork design [6,[14][15][16][17][18][19][20]. Kannan and Santhi [15] conducted research on the automation of formwork systems using a building information modeling (BIM) software. ...
... Lee et al. [16] developed a method of collecting field labor productivity data and calculating the productivity by integrating a 3D model with the information obtained from a BIM model. Subsequently, Lee et al. [17] proposed a search algorithm to minimize manual efforts and optimize the formwork panels around structural obstacles. Lee and Ham [18] examined an automated form layout system that arranges standard and nonstandard slab-forms to increase the work efficiency and save manufacturing cost. ...
... Meanwhile, to support the formwork design, various applications such as Tekla Structures, PERI CAD, ELPOS, Tipos, and DokaCad have been developed by formwork manufacturing companies [17]. The representative example is Tekla Structures, which is a formwork design application based on BIM. ...
This study developed a formwork automation design software that interprets 3D building information modeling (BIM) data from the 2D CAD data of a target structure. This software aimed to identify the quantity and types of formworks and situations that may occur at construction sites. A prototype that can implement 3D automation design, automatic formwork layout, and statistics function was developed for simple target structures; this confirmed the possibility of developing the software, for which a preliminary study was conducted to convert random vertices in the BIM data of the target structure to forms with certain rules. The meshes were transformed into a constant form using an algorithm that fills a 3D model with identical square meshes. Additionally, an algorithm was developed by setting and prioritizing specific rules for the faces. The software operation result confirmed the possibility of automatic formwork layout of wall and deck members.
... To address these issues, studies have applied various algorithms and advanced systems to formwork design [9][10][11][12][13][14][15][16][17]. A study was conducted on the automation of the formwork system based on the development of building information modeling (BIM) software using Revit and AutoCAD [11]. ...
... and calculated the amount of formwork required for a project based on the use of the data extracted from the BIM model [12]. A study was conducted to propose a search algorithm to optimize formwork panels [14]. Research has also been conducted on an automated form layout system that arranged standard and nonstandard slab forms to increase work efficiency and reduce manufacturing costs [15]. ...
... Meanwhile, formwork manufacturing companies have been developing various programs to support formwork design. For instance, typical programs include Tekla Structures, PERI CAD, ELPOS, Tipos, and DokaCad [14]. However, using these programs is inconvenient given that formwork designers need to directly set contact points. ...
In this study, by applying the developed formwork automation design software to three target structures, we reviewed the applicability of the formwork automation design software for the aluminum formwork. To apply the formwork automation design software, we built an aluminum formwork library based on the conversion of two-dimensional (2D) computer-aided design (CAD) data to three-dimensional building information modeling data for all the components of the aluminum formwork. The results of the automated formwork layout on the target structures using the formwork automation design software confirmed that the wall and deck members were laid out by the set algorithm according to the formwork size and direction. However, because of the limited functionality of the software, the level of completion of the formwork layout was found to be lower than that of the manual formwork layout based on 2D CAD data. The currently developed software is based on a simple algorithm, but has a drawback in that the automated layout is limited to only some of its members. Therefore, additional research should be conducted on the development of advanced software through the diversification of the algorithm, automation of preprocessing of the mesh, and analysis of the relationships of all the members comprising the formwork.
... In order to improve safety performance and labor productivity, optimum layout of temporary facilities can be generated through simulation-based methods within the restricted sites [2,17]. The optimization criteria involved in temporary facility planning were identified to assist with the planning task using heuristic algorithms [6,9,[18][19][20][21][22][23]. To automate layout planning, Building Information Modeling (BIM) -based system can support the dynamic generation of site layout models, instead of manually inputting the information data [24]. ...
... Within a construction site, temporary facilities, such as equipment (e.g., cranes and scaffoldings), job offices, storage areas, warehouse, fabrication shops, and batch plants, are needed by work crews to support their task operations and various activities [2][3][4][5]. In order to improve the project profitability, labor productivity, safety, quality and controlling ability of project cost, the project managers need to conduct an effective temporary facility layout planning process properly during the construction planning phase [6][7][8]. An appropriate layout plan of facilities can reduce the construction expenses by up to 50 percent [9, 10]. ...
In construction projects, the planning objectives include the safety and labor productivity of the activities, along with the cost influence affecting the overall performance of construction. Temporary facilities are critical in supporting structures and equipment that impact the direct task executions and resource transportation during various construction stages. The positioning of temporary facilities and the relative spatial relation between multiple facilities are critical factors that affect the success of construction delivery. To ensure the balance among safety, labor productivity and construction cost performance, all influencing factors associated with the construction objectives should be taken into account in temporary facility layout planning. This paper proposes a novel multi-criteria temporary facility layout planning model that integrates Analytic Network Process (ANP) modeling and simulation-based sensitivity evaluation, which effectively transforms the spatial layout planning problem into a mathematical decision problem. An application example is analyzed to demonstrate its capabilities of optimizing temporary facility layout planning. The proposed framework provides the construction managers and layout planners with a useful tool for selecting the optimal alternative of temporary facility layout plan on the construction site.
... Automatic extraction of material quantities required for wall assembly was proposed by Manrique et al. in a 3D CAD model [23]. A specialized technique for placing formwork panels around columns was suggested by Lee et al. [24], enabling ideal formwork placements even for intricate floor plans with numerous columns. The harmony search optimization algorithm is used to rapidly and automatically determine cohesive and ideal layouts. ...
Material planning is important in construction, for it affects procurement, cost, and schedule. Proper planning of material supply and logistics helps streamline the performance of all tasks through the avoidance of excessive or insufficient material supply. Material planning relies on quantity takeoff (QTO) and project schedules. Conventionally, quantity takeoff was a manual process based on 2D drawings and human interpretation and was error-prone. Presently, with the popularity of Building Information Modelling (BIM), in BIM-based projects, using inbuilt quantity takeoff functions, quantities of work can be generated automatically from BIM models to aid the quantity takeoff. However, if those inbuilt QTO solutions are object-based, then the quantities of works extracted may not meet the requirements of the users in selected cases, e.g., in zone-based construction projects. Also, for estimating daily material requirements, the accuracy of the quantities of work becomes more important, not only for the purpose of efficient planning but also for reducing construction waste. Since works using the same type of material can go overlapping, in addition to estimating the amount of material for each work, the total amount of material for a day must also be calculated. Thus, this research aims to develop a framework for automatic extraction of zone-based concrete volumes and formwork positions for cast-in-place concrete structures using the data in BIM models, followed by linking them with project schedules for estimating daily concrete and formwork requirements. This framework extends the body of knowledge by introducing an innovative algorithm for automatically calculating overlapped areas between concrete members and a rule for naming tasks in the schedule, followed by evaluating the formwork requirements without drawing formwork in a 3D model. A software tool will be developed to achieve the aim, and a case study will be used to validate the proposed framework.
... This model is only applicable to wooden formwork. Lee et al. (2018) used HSA to design the formwork while cutting costs by using fewer nonstandard panels for irregular-shaped slabs. Lee et al. (2014) presented a formwork layout model that uses GA to lower the cost of formwork materials. ...
Purpose
Formwork design and construction for reinforced concrete buildings take significant time, effort and money. Construction procedures are time-consuming for designers and costly for the contractor. Poor engineering decisions have led to several workplace accidents in the construction industry. This paper aims to present an integrated building information modeling – genetic algorithm (BIM-GA) model to automate formwork design, 3D visualization and optimization.
Design/methodology/approach
Data are precisely extracted from a 3D structural model and used to optimize formwork design based on available formwork components and prices. Optimization models are made using GA approach. A library of 3D formwork components was modeled and stored using Revit. The optimized design solution thereafter would be visualized automatically in Revit to readily acquire formwork quantities schedules and shop drawings.
Findings
A case study illustrating the proposed approach demonstrated that using BIM will reduce formwork design, quantification and drawing time by more than 50% of the traditional approach with safer design and accurate results due to process automation and optimize cost for the given data.
Originality/value
This research introduces an innovative integrated BIM and GA model for the optimization and automation of slab formwork design, which has significantly benefited the construction industry. The utilization of GA in the optimization process allows for the attainment of an optimal formwork design, ultimately leading to a reduction in construction cost and time.
... Исследователи в работе [10] рассматривают опалубку, как совокупность элементов и деталей, предназначенных для образования формы монолитных бетонных или железобетонных конструкций и сооружений, возводимых на строительной площадке В исследовании [11] авторы рассматривают опалубку, которая должна обеспечивать заданные размеры и форму возводимой конструкции; быть прочной, жесткой и неизменяемой в рабочем положении и при воздействии всех производственных нагрузок; иметь минимальную адгезию (сцепление) поверхности с бетоном; быть индустриальной и многооборачиваемой, экономичной и технологичной при сборке и разборке, а также не создавать затруднений при установке арматуры и укладке бетонной смеси. ...
The object of the study is the building of the National Space Center in Moscow. Method. In the course of research, the provisions of system analysis, methods of expert assessments, risk theory, methods of economic and mathematical modeling, simulation modeling, comparative method, method of generalization, abstraction, induction and deduction were used. Results. The analysis of theoretical sources and calculated data based on the project of a high–rise construction object was carried out, as a result of which the criteria for the characteristics of the object were established, providing conditions for the economically profitable use of self–lifting formwork, and a financial and economic model for justifying investments in this project was built.
... Although Buitrago et al. solved an optimization problem that involved shoring planning as parameters to obtain the best construction process through heuristic optimization, they considered only the clearing percentage of shoring and not the detailed arrangement of the props [14]. Lee et al. proposed an optimization system for formwork layout planning to reduce manual efforts using a harmony search algorithm; however, they did not consider the arrangement of shore [15]. For examples of optimizations for RC buildings, Chepurnenko et al. proposed a stochastic method to obtain an optimal solution, such that the objective functions were the deformation and potential energy of the slab and reinforcement consumption for monolithic RC slabs [16]. ...
For the construction of reinforced concrete buildings, partial striking of props and formworks a few days after casting is frequently employed, confirming its safety based on structural calculations or analyses to improve the construction productivity. Three-dimensional finite element (FE) models are sometimes used for these kinds of structural analyses to obtain precise results. However, considerable effort is required to determine the remaining prop arrangement by trial and error via FE analysis because of time-consuming operations. This study presents continuous optimization methods for the determination of the arrangement of remaining props that can speedily provide a single valid solution based on design sensitivity; the solution guarantees local optimality. Continuous optimizations employ a function that transforms the continuous design variables into the number of remaining props at each candidate location that is inherently represented by integer values. The optimization problems have been formulated in two forms: one is to maximize the safety of the structure, and the other is to minimize the number of remaining props. These optimization methods provided valid local optimal solutions that could reduce the amount of material required for formwork and shoring by almost half within a realistic calculation time. In addition, compared with multi-objective discrete optimization by a genetic algorithm, the first method provided the optimal solution with less than half the number of FE analyses of discrete method, and the second method provided a more efficient solution than the discrete method with a total of 10,000 individuals.
... The use of advanced software in preparing construction work packages and the development of three-dimensional (3D) models are some of the potential areas where the productivity of construction projects could be gained (Lee et al. 2021(Lee et al. , 2018. For multistory building projects, the use of software for planning purposes can help reduce errors while preparing the work breakdown structure and sequencing of tasks (Sadler 2021). ...
Implementation of appropriate management practices before commencing construction is vital to enhance construction productivity. This study aims to identify and prioritize preconstruction phase management practices (PCMPs) that can improve labor productivity in multistory building projects. Additionally, the objective of this research is to develop a stochastic model for predicting labor productivity based on the level of implementation of PCMPs. A thorough review of the literature was conducted to identify the practices that can increase construction productivity. Thereafter, questionnaires were distributed to principal contractors, and quantitative data were collected. After analyzing the data, the PCMPs were prioritized and a probability-based labor productivity prediction model was developed. The findings of the study revealed that well-defined scopes of work, short-interval plans, and buildability review are the top three PCMPs that can enhance labor productivity in multistory building projects. Correlation analysis showed that the relationship between labor productivity and PCMPs is statistically significant. The research showed that the relative importance of PCMPs varies based on project type. This study contributes to the body of knowledge by developing a novel tool to assess the levels of implementation of PCMPs and by building an innovative stochastic model for estimating labor productivity. Contractors can implement the practices identified in this research to augment the labor productivity of building projects, and use the model and a scoring tool to predict the labor productivity of multistory building projects.
... The application of machine learning in the world of construction has been widely applied, one of which is the planning mapping of needs and formwork areas as done [9] in his research journal which explains how machine learning can develop the planning and procurement of the amount of formwork for an atypical building area. This process saves time and resources, the identification results of machine learning are more detailed and accurate than the identification of formwork requirements that is done manually. ...
Achieving project objectives that are effective, efficient, and safe requires careful planning of construction methods. The construction method of a project may vary depending on the description and design of the project. Planning for construction methods generally takes a long time to review, involves many parties, and requires consideration in terms of costs, resources, and safety. And the need for construction planning characteristics for smart buildings recently. Machine learning combined with the blockchain system is an instrument that can accommodate processes in the construction method. Start from planning to integration-evaluation with a historical database. This instrument is expected to be able to provide suggestions and evaluation of methods, to be able to assist the planning process of construction methods so that the application of work methods will be more effective and efficient.KeywordsConstruction methodSmart buildingMachine learningBlockchain
... For instance, the size of the building construction projects (e.g., the total area of building construction) significantly affects some FWS selection criteria, such as labour productivity [52]. Furthermore, depending on the type of the project and the structural design of the structure [122,123], labour productivity and labour cost of the FWS may be critical factors in building construction projects, particularly high-rise ones [22,124]. The weather conditions, such as high wind speeds, may also affect the labour productivity of formwork-related activities [125]. ...
The successful completion of reinforced concrete (RC) building construction projects depends , in part, on selecting the appropriate formwork system (FWS) since it may significantly affect the project's cost, time, and quality performance factors. The selection of the FWS depends on a number of compromising and conflicting criteria, while several FWS alternatives may be available. Therefore, the FWS selection has mostly been treated as a multi-criteria-decision-making (MCDM) problem. Although various MCDM methods have been employed to address the FWS selection problem, none have considered the subjectivity and uncertainty arising from a group decision-making process. This study aims to fill this knowledge gap by proposing an integrated approach using recently developed MCDM methods with rough numbers. In the integrated approach, first, a decision making team is formed to develop the decision hierarchy. Then, the rough analytic hierarchy process (R-AHP) is used to determine rough criteria weights, followed by the rough evaluation based on the distance from average solution (R-EDAS) method to rank the FWS alternatives. Finally, the results are compared using different rough MCDM methods to ensure the stability of the proposed approach. The proposed approach is applied to a real-life building construction project in Turkey to select the most appropriate FWS. The integrated approach was found to be effective, and it was recommended to be used for future FWS selection problems. The proposed integrated approach in this study may be used as a decision support tool for construction professionals and experts to select the FWS in building construction projects.
... These issues can be assumed as emerging considering that a growing trend in the number of documents is observed. It is worth noting the emerging nature of planning construction processes for highway projects, a phenomenon that contrasts with building projects, in which an overall development is observed [126][127][128][129]. Therefore, in the coming years, there is expected to be a growing development of the theme of planning construction processes for highway projects based on the adaptation of technologies that have been tested and improved in building projects. ...
An efficient highway infrastructure network is a determining factor in promoting the socio-economic development of countries and regions. Highway planning activities are highly important because their results ensure that projects are delivered within budget, schedule, and scope. Therefore, academics and professionals have promoted various methodological and technological advances focused on improving highway planning processes, evidenced by many scientific documents that address the topic. Despite progress, few studies have focused on analyzing the state of the knowledge structure and the technological and methodological trends of the highway planning topic. Considering this gap, this study presents trends in highway planning and its knowledge structure based on a bibliometric analysis from January 2015 to September 2021. The research method is based on a bibliometric analysis composed of five main stages: (1) scope definition, (2) selection of bibliometric analysis techniques, (3) data collection, (4) bibliometric analysis execution, and (5) evidence analysis and synthesis. Information from 1703 journal papers was collected and analyzed. The findings show that the main trends of highway planning focus on life cycle analysis, computational tools, smart cities, sustainability issues, construction processes, new equipment and materials, and multi-objective optimization, among others. Thus, the findings of this study allow the reader to identify the methodological and technological trends in highway planning and their knowledge gaps to guide future studies in the field.
... For example, the FWS selected based on the FWS selection criteria and its effects on the project time, cost, and quality performances can be studied quantitively by considering the relationships among FWS selection criteria groupings. According to some studies, the FWS design and selection are mainly affected by the structural design criteria of the building construction project, e.g., [11,12]. Therefore, the structural design may also affect the project performance. ...
Selecting the appropriate formwork system (FWS) is a critical aspect in the successful completion of reinforced concrete (RC) building construction projects. The selected FWS has a significant impact on the cost, time, and quality performances of the project. As there are many FWSs and formwork fabricators (FWFs) available, the selection of the FWS depends on several compromising and conflicting criteria. This study aims to identify the FWS selection criteria groupings (e.g., latent factors) and investigate the quantitative interrelationships among them. For this purpose, 35 FWS selection criteria were identified through literature review, and a questionnaire was developed. The data from the questionnaire were statistically analyzed, and five latent factors were identified: FWS-FWF characteristics, structural design, local conditions, cost, and performance indicators. A conceptual framework was developed based on the latent factors, and a structural equation modelling (SEM) approach was utilized to identify the effects among the latent factors. The results of the SEM approach confirmed that FWS-FWF characteristics are affected by the structural design and local conditions and FWS-FWF characteristics have a substantial effect on cost and the performance indicators of the project. The findings of this study may assist construction professionals in selecting the FWS in building construction projects.
... In a case study in Cincinnati, Ohio, Mansuri et al. (2017) used building information modeling (BIM) in conjunction with a cascading tool to show that the method reduced the cost and was more productive for workers, and improved formwork productivity, efficiency, and accuracy. Lee et al. (2018) used a harmony search algorithm (HSA) to demonstrate improvements in worker formwork installation and significant cost reductions from using less nonstandard material and fewer panels. They concluded that HSA was more efficient than a genetic algorithm (GA) in the planning process. ...
Formwork is an essential part of construction engineering, whether for floors or for walls. This research focused on wall formwork,
which is used in residential buildings. This study primarily was concerned with reducing the cost of the formwork using optimal
sections and optimum casting rates. The methodology of this research consisted of using equations to determine the lateral pressure of
concrete on the formwork, to calculate the minimum spacing between the formwork components to obtain an economical and safe design,
to calculate the optimum casting rate, which is 1.5 m=h, and to find the optimum lateral pressure. DOI: 10.1061/(ASCE)SC.1943-
5576.0000684. © 2022 American Society of Civil Engineers.
... However, no prior study has investigated whether there are any significant statistical differences/disagreements in the relative importance of FWS selection criteria among different groups of construction professionals and/or companies. Moreover, some building structural parameters (e.g., total building area, total building height) of the building construction project may significantly affect the FWS design and selection [14,15]. Hence, the effects, if any, of the building structural parameters on the FWS selection criteria may reveal some valuable insights for construction professionals in their decision-making process. ...
The formwork system (FWS) in reinforced concrete (RC) construction is a critical component. The appropriate FWS is selected based on a number of conflicting and compromising criteria, and the selection of the FWS is carried out by construction professionals with different technical and/or administrative backgrounds. The perspectives and perceptions of construction professionals and companies involved in the FWS selection process may vary depending on their motives. In addition, some building structural parameters may have a significant impact on the FWS selection criteria. Most of the former studies investigated the FWS selection criteria from only the perspective of contractors and neglected the potential differences in the perspectives and perceptions of different construction professionals (i.e., owners (CO), project managers (PM), construction managers (CM), site engineers (SE), planning engineers (PL), procurement engineers (PR), technical office engineers (TO), and formwork design and/or formwork sales engineers (FD/FSL)) and companies specialized in different fields (i.e., project management service (PMS), engineering and design (ENG/DSG), formwork and scaffolding (FW/SCF), and general and/or subcontractor (GC/SC)) regarding this issue. Moreover, the impact of building structural parameters on the FWS selection criteria has not been investigated. This study aims to fill this knowledge gap through analysing the FWS selection criteria for building construction projects while comparing the perspectives and perceptions of different groups of construction professionals and companies and investigating how FWS selection criteria are affected by the building structural parameters. Based on a comprehensive literature review, 35 FWS selection criteria were identified and a questionnaire was developed. The questionnaire data obtained from 222 Turkish construction professionals were statistically analysed using mean score analysis, the Kruskal-Wallis test, and the Mann-Whitney U test. According to the study's findings, the FD/FSL group presented significant statistical differences regarding the FWS selection criteria as compared to the CO, PM/CM/SE, and PL/PR/TO groups. Moreover, the total area of building construction and total building height significantly affected the FWS selection criteria. This study serves to underscore the perspectives of various groups of construction professionals and the critical connection between the structural parameters and FWS selection criteria. The findings of this study may guide construction professionals to select the appropriate FWS for their building construction projects.
... It is helpful for the organisation in the sector of construction to manage the business operation in the potential marketplace by meeting the needs of the consumers. Quality management is an essential aspect in this regard (Lee et al. 2018). As for this reason, the material of formwork is used in this context. ...
Formwork materials are useful in the project of the construction. It has several effects on the quality of the project. This research study has described the effects of the formwork materials in a well manner. Benefits of the materials are discussed in this regard. Flowchart is given in this study for understanding the work process of the formwork materials in the project of construction. Diagram as well as statistical data from other research paper are also included in this study. At the end a profound conclusion has been drawn.
... It uses standard prefabricated modular units with various sizes of formwork panels. The modular components are assembled on-site in different combinations with the aid of computer-aided design (Lee et al., 2018), and minor conventional formwork typically made of timber is required to complement the system by filling gaps. The system form has high productivity and good casting quality as well as can be recycled more times than conventional forms such as timber and wood-based form, and various types of system form have been developed to suit the required shapes of concrete structures with less effort, especially in urban city construction. ...
System form is widely used when constructing concrete buildings and structures because it has high productivity and good concrete casting quality compared with traditional hand-set form. However, from a worker’s perspective, system form is still very harsh to handle because of its heavy weight, noise generation, and use of releasing agent, and it also attenuates the productivity of system formwork. Therefore, this study proposes the use of an advanced composite material-based concrete form for workers using a Design for Six Sigma (DFSS) process to improve constructability of system formwork. User requirements are systematically reflected in the technical characteristics of concrete form, and innovative principles are scientifically organized through the DFSS process that mainly consists of quality function deployment and theory of creative problem-solving methods. The proposed composite form showed improved performance in deriving high-quality formwork and worker-friendly working conditions compared with previous system forms. Additionally, this study demonstrated how the DFSS will be a valuable tool for technology development and systematic decision-making in building construction.
... Furthermore, Mansuri et al. (2017) proposed an approach to using data drawn from building information models coupled with a cascading algorithm to efficiently manage formwork inventory on a construction project by generating a scheduled formwork reuse plan and calculating the minimum quantity of formwork required for the project. Lee et al. (2018) suggested a specialized method for deploying formwork panels around columns. The proposed approach used a harmony search algorithm (HSA), and the study demonstrated improvements in the work efficiency of formwork and reduced formwork costs by minimizing both the use of nonstandard panels and the total number of panels. ...
Setting the baseline labor productivity (BP) values for construction activities is essential to compare the productivity performances of projects or contractors. The BP value can also be used to estimate the costs incurred due to the loss of productivity on a certain project. The objective of this research is to develop a Monte Carlo simulation-based baseline labor productivity model (MCBPM) that can be used to determine the BP value for formwork operations. After proposing a framework for the MCBPM, empirical data regarding the labor productivity of timber formwork for several building structures were collected from 40 contractors in Ethiopia. Thereafter, a Monte Carlo simulation was carried out to simulate the formwork labor productivity, and BP values were set. Following the simulation, the BP values for column, beam, slab, and wall formworks, at 95% probability, were found to be 0.94, 0.80, 0.93, and 1.0 m 2 =h, respectively. Compared to the previous BP models, the MCBPM provides more reliable estimation accuracy and efficiency to set the BP value based on the confidence level. This study contributes to the body of knowledge by proposing a stochastic labor productivity model that can be used as a practical tool in construction projects to forecast the BP values at certain confidence levels.
Selecting an appropriate formwork system becomes complex as one must take into account various factors and their impacts in order to make informed decisions tailored to each specific project. Thirty-three influencing factors were identified specifically for consideration when choosing the formwork in the Vietnamese context. After analysing data collected through a survey with these persons working in the construction field, the study has identified primary groups by using Exploratory Factor Analysis (EFA). Next, the study creates an Analytic Hierarchy Process (AHP) to compare the alternatives for selecting formwork within the scope of considering the evaluation criteria discovered from the previous factor analysis step. The results of this investigation clarify the primary determinants influencing the choice of formwork systems and concurrently pinpoint the optimal alternative via the formulated model. Additionally, the outcomes of this study aim to enhance managerial awareness concerning formwork techniques and promote the widespread utilization of decision support tools in high-rise construction projects. This initiative has the potential to improve the accuracy of planning operations and enhance the success of construction projects.
The proper formwork system is one of the most important factors in the success of high-rise building construction projects. However, this work is complicated when it is necessary to consider many aspects of impact to make the right decision for each project. Through conducting a survey with respondents who are individuals and experts in the field of construction, the research aims to determine the factors influencing the decision to choose formwork in the construction of high-rise buildings. After analyzing data collected from 190 valid responses with SPSS software, the research has identified 6 main groups based on 33 factors given in the survey. The research results have determined the greatest influential factors on formwork choice. From that, the results of this study shall assist managers in expanding their understanding of formwork systems, supporting planning and decision-making more successfully, and contributing to the success of today’s high-rise building construction projects.
The cost of producing one cubic meter of concrete structure, depending on the structure’s shape, type, and complexity, can be variously high. The cost of concrete, reinforcement, formwork, and labor ratio varies. But unlike the cost of concrete and reinforcement, which tend to be similar in the terms of the conditions of a particular construction project, the cost of formwork and work with it are different for different contractors. It often depends on the appropriateness of the formwork system used, the optimal placement of the formwork sets, the minimization of downtime, and the efficiency of the carpenters’ work. Formwork modeling in the construction preparation phase intervenes in this planning area, where construction sources are defined and quantified, and the time course of their deployment is determined. The current paper deals with optimizing formwork selection and deployment in concrete structure execution. Even if several requirements must be considered when selecting and modeling the formwork (e.g., construction time, quality of concrete structure, etc.), an effort to minimize the cost of formwork, and thus construction cost, plays the most significant role. A dynamic model for effective and optimal planning of formwork in construction projects, including formwork cost analysis, is presented in the paper. The included case study demonstrated the planning of the formwork through a software application developed based on the computational algorithm of the dynamic model presented. A case study is presented in the article as a research method. An office building with five above-ground floors and one underground floor was chosen for the case study. To solve the case study, the formwork for horizontal structures (i.e., beams and slabs) is considered. The goal of the case study is to identify research questions and apply time and cost optimization to a selected specific building.
Concrete formwork is a system supporting and shaping concrete components and its potential reuse has been increasingly considered in recent years. On-site concrete formwork reuse contributes to cost savings and material waste reduction. However, concrete formwork reuse among different construction sites is still limited. In addition, on-site formwork planning is inherently complicated, and dynamic processes of formwork reuse increase the complexity since on-site emergencies result in various changes. This study aims to provide an appropriate approach to analyze the dynamic processes of formwork reuse among construction sites, for minimizing both the total cost of each site and the overall formwork consumptions. A mathematical model is first developed to analyze formwork utilization on a single site, and an agent-based model is then proposed along with discrete events to implement and simulate formwork reuse with dynamic changes among construction sites configuring a supply chain. The mathematical model minimizing the total cost of concrete formwork enables the understanding of decisions and behaviors of a single construction site and provides a basis for simulation modeling. In the agent-based model, four major decision agents consisting of construction sites, commercial formwork suppliers, waste disposal centers, and transportation trucks are developed. Considering asymmetric information, a negotiation protocol is integrated into agents’ behaviors to facilitate interactions. With the agent-based modeling and simulation, the optimal strategies for construction sites to reuse formwork can be generated. The results of a case study indicate that formwork reuse in the supply chain can outperform that on a single site and results in a cost saving of 25.38%, a quantity reduction of 33.56%, and a surplus reuse value reduction of 73.18%.
This paper aims at developing a model to measure and evaluate the performance and productivity of the construction of steel structure projects (SSP). Practitioners and experts comprising a statistically representative sample were invited to participate in a structured questionnaire survey to achieve the objective. The questionnaire consisting seventeen factors that were classified under the following four primary categories, with terms such as feasibility study stage, planning stage, design, and engineering stage, and construction stage. Using Artificial neural networks (ANNs) for designing a model on Matlab for measuring and evaluating the projects’ performance of the Construction of SSP based on the fourteen (14) factors that affect the steel structure process. The results suggest that the proposed ANN model for SSP can produce measures and evaluate the projects’ performance quickly and accurately when actual data is available for model training. The user can enter the values of main factors that affect their projects’ performance to produce an accurate output of the evaluation for the projects’ performance and productivity. The construction industry can use the findings of this paper as a basis for improving the projects’ performance of the Construction for SSP.
In case of construction investments, the cost estimation was always important. The reason for this is that after the planning, the most important issue is the cost of the investment. There are many different estimation methods. These estimates may vary in depth, depending on the task and the plan. The question is what happens if we wanted to predict not only the total cost of the investment but also the cost of some parts and structures. Such a cost element is the formwork cost of the monolithic reinforced concrete structures. This is a special processing aid, which makes it difficult to calculate accurately. The study is based on a cost analysis of the construction of 22 completed buildings over the last 10 years. Here, the cost of the formwork was compared to the total cost of the construction. By examining the 22 buildings together, we made findings over the years. We wanted to find out how much the construction price changes affected the structure and the formwork costs. The other direction of our research was the cost analysis within each building type, focusing on the formwork. In this analysis, we defined six types of buildings, such as detached, dwelling, condominium, public, office buildings, and other types of buildings. This study does not include the cost of the formwork types specific to each component, but from the foundation to the ascending structures, it analyses them in a single system.
Building construction is an object of a certain part of a building. Planning an earthquake-resistant building structure, one of the methods used is the Intermediate Moment Bearer Frame System (SRPMM). Based on SNI 03-1726-2012, SNI 03- 2847-2013, and SNI 1727-2013. In modeling made using SAP 2000 V20. The planning of the Permata Indah building, which is in Nganjuk Regency, is reviewed using static equivalent and response spectrum. The moment-bearing frame system is when the components and joints resist bending, shear, and axial forces. In this case, the moment-bearing frame system has a concept on the ductile portal structure system for joints or joints between columns and plastic beams. The calculated structural part is a floor plate that uses evenly distributed loads in trapezoidal loads and triangular loads; beam and column systems use concrete with analysis and calculation using the SAP 2000 V20 program. 9-D16 stirrup reinforcement Ø10-80, beam size 20cm x 25cm with main reinforcement 6-D16 stirrup Ø10-90, column size 30 cmx55 cm with main reinforcement 10- D16 stirrup 3 Ø10-110, practical column 15cm x 15cm 10 -D19 stirrup 3 Ø10-110, x and y-direction plate size Ø10-150 and Ø10-150. Konstruksi bangunan merupakan suatu obyek dari bagian tertentu dari suatu bangunan. Perencanaan struktur bangunan tahan gempa, salah satu metode yang digunakan adalah Sistem Rangka Pemikul Momen Menengah (SRPMM). Berdasarkan SNI 03-1726-2012, SNI 03-2847-2013, dan SNI 1727-2013. Dalam pemodelan dibuat dengan menggunakan SAP 2000 V20. Perencanaan gedung Permata Indah yang berada di Kabupaten Nganjuk ditinjau dengan menggunakan statik ekuivalen dan spektrum respon. Sistem rangka bantalan momen adalah ketika komponen dan sambungan menahan gaya lentur, geser, dan aksial. Dalam hal ini sistem rangka bantalan momen mempunyai konsep pada sistem struktur portal daktail untuk sambungan atau sambungan antar kolom dan balok plastik. Bagian struktural yang dihitung adalah pelat lantai yang menggunakan beban merata pada beban trapesium dan beban segitiga; Sistem balok dan kolom menggunakan beton dengan analisa dan perhitungan menggunakan program SAP 2000 V20. Tulangan sanggurdi 9-D16 Ø10-80, ukuran balok 20cm x 25cm dengan tulangan utama sanggurdi 6-D16 Ø10-90, ukuran kolom 30 cmx55 cm dengan tulangan utama sanggurdi 10-D16 3 Ø10- 110, kolom praktis 15cm x 15cm 10 -D19 sanggurdi 3 Ø10-110, pelat searah x dan y ukuran Ø10-150 dan Ø10-150.
The composite construction has always been the area of interest for structural engineers as the use of two or more material to make one structural member have always proved to be beneficial. The concrete-filled steel tubes (CFST) and concrete-encased steel (CES) columns are gaining popularity and have been adopted for the construction of high rise buildings. In the present work, CFST columns and CES columns subjected to axial compression were analysed. The columns are assumed to be having fixed-free end and the loads were applied on the loading plate for even distribution of loads. The circular, square and rectangular shapes of columns are considered. CFST columns were considered for varying steel tube thickness of 3 mm, 5 mm and 7 mm, and the I-section selected was ISMB 100 for CES columns. CFST and CES columns were analysed separately. The behaviour of these columns and their ductility was studied. The analysis was carried out using the finite element software ABAQUS. The modelling and meshing were done in the software and analysed. The loads versus deformation graphs are plotted for each column. The ductility factor and load carrying capacity for all CES and CFST columns are compared. The circular CFST column with 7 mm tube thickness was found to be the better in terms of ductility and load carrying capacity.
The principle of building design is to achieve the assigned objectives under the prescribed demand. Cases of large-scale damages to structures are due to unpredictable, higher-level loading, arising out of environmental loading; blast loading is one of them. The purpose of this research is to calculate blast parameters by analytical approach and obtain the pressure variation on different faces of building using IS:4991-1968. Three explosion weights (100, 500 and 1000 kg) are exploded in three different standoff distances (15, 30 and 45 m) and at 0, 6 and 12 m vertical in air. Blast parameters and pressure variation on different faces of building are calculated for different explosive weights and respective distances.
Improving productivity, increasing output for the same inputs have been a longstanding concern of the construction industry. The different approaches to improving labour productivity in formwork will be briefly explained. The influence of the buildability elements on formwork labour out of key in situ reinforced concrete factors such as foundations, walls, columns, beams and slabs is yet to be gritty and quantified. The key results of several questionnaire surveys will be presented, and the major deterrent to improve buildability and by which buildability problems are being overcome are identified.
The study of frequency analysis is crucial to find the most fitting model that could predict extreme events of certain natural phenomena, e.g., rainfall, flood. The study aims to determine the best-fit probability distribution model for the maximum daily rainfall of four stations in Mangalore city. Statistical analysis such as log-normal, log-Pearson, and generalized extreme value (GEV) was applied, and parameters of these distributions were estimated. The predicted values using these distributions subjected to the goodness of fit test using the Kolmogorov–Smirnov test, Anderson–Darling test, and Chi-squared test. Generalized extreme value distribution gave the best-fit model and thus, used for deriving the intensity duration frequency (IDF) curves for Mangalore city. IDF curves using the empirical equation and GEV distribution were compared, and GEV distribution IDF curves give higher rainfall intensities.
Tunnel form system formwork is one type of modern system of formwork that is used for construction purposes. This system has become a prime and permanent construction technique for construction of building in the country along with many foreign countries. This system is an emerging technique for construction purpose due to its efficient construction technology, minimum duration utilized and low estimated budget cost in the construction project. This paper reviews the main comparison of the tunnel form system formwork with the MIVAN formwork technique which is the frequently used technique in the country. Moreover, the working process, advantages, disadvantages along with characteristics and limitations of the formwork system as compared to the behaviour of the structure has also been reviewed. The MIVAN formwork technique also referred to as aluminium formwork provides much faster mode of construction work with easy access all over the country as compared to tunnel form system formwork. This review paper also highlights the failure and hazardous activities of the tunnel form system formwork mentioning with case studies along with the benefits or usage in designing, shuttering process, de-shuttering process and dismantling process. This review paper also highlights the modified and advanced analysis of both the formwork systems and its comparison with the scheduled duration and the estimated cost budget of the construction project. The break-even analysis of both the formwork systems has also been compared in this review paper.
Due to rapid population growth and constraint on land availability, construction sector spread its wings in vertical dimension. As high-rise buildings are stretching toward sky, challenges with structural behavior govern the choice and design of structural system. Lateral load resisting systems popularly in use are moment resisting frames, load bearing structural walls, dual systems, tube system, and moment-resisting frames with outrigger. The intent of the work in this paper is to investigate the performance of outrigger, location optimization, and their efficiency when used in multiple numbers placed at various heights (2/3rd, 1/2th, 1/3rd times the height of building). Models of 30 storey buildings with outrigger and belt truss systems are analyzed for earthquake and wind loads and the lateral drift responses are compared to find the optimum location of outrigger and belt truss systems. The results are interpreted and found that outrigger system can effectively reduce the lateral drift of the building and optimum location of outriggers is found to be at mid-height of building considered along with cap truss.
In order to effectively design nearly Zero Energy Buildings, the assessment of energy performance in the early design stages through simulation is an important, although very demanding and complex, procedure. Over the last decades, various tools and methods have been developed to address performance-related design questions, mostly using Multi-Objective Optimization Algorithms. Technological advances have revolutionized the way Architects design and think, automating complex tasks and allowing the assessment of multiple variants at the same time. In this paper, a new nZEB design workflow methodology is proposed, integrating evolutionary algorithms and energy simulation, and its capabilities and current limitations are explored.
Efficient layout planning of a construction site is fundamental for successful project undertaking as it enhances both productivity and safety in construction sites. This task usually consists of identifying the temporary facilities needed to support construction operations, determining their size and shape, and optimally positioning them in the unoccupied areas within the site boundaries. The site layout planning problem is a complex combinatorial optimization problem involving multiple objectives and it grows significantly in size as the number of facilities and constraints increases. The existing literature includes a variety of analytical, heuristic, and meta-heuristic techniques for solving the problem but existing studies usually examine a small number of facilities and focus on travel distance minimization, ignoring generally cost related or other decision parameters. The objective of this study is to develop feasible and efficient site layout solutions in a realistic representation scheme taking into consideration not only the total distance traveled but also cost and safety parameters as well. A multi-objective optimization model is developed aiming at minimizing a generalized cost function which results from the construction cost of a facility placed at alternative locations, the transportation cost among locations, and any safety concern in the form of preferred proximity or remoteness of particular facilities to other facilities or work areas. The development integrates the required robust search objective with the optimization capabilities of the genetic algorithms (GAs). The model has been tested on several test cases and the results of a comparative study with existing methods from the literature are presented. The evaluation indicates that the proposed model provides effective and rational solutions, in response to decision parameters and problem constraints, and that it results in more robust layout planning than previous methods both qualitatively and quantitatively.
In this paper, harmony search algorithm is utilized for the optimum design of slabformwork. This method is a numerical optimization technique developed recently that imitates the musical performance process when a musician searches for a better state of harmony. The cost of the form components involved is considered as the objective function of the optimization problem. Constraints for the optimization problem are bending moment, shear, maximum deflection and imposed ACI code provisions. The use of the harmony search to formwork design problems provides optimum cross sections and optimum spacing of the form members (joist and stringer), while minimizing the total cost.
In this article, harmony search algorithm was developed for optimum design of steel frames. Harmony search is a meta-heuristic
search method that has been developed recently. It bases on the analogy between the performance process of natural music and
searching for solutions to optimization problems. The objective of the design algorithm is to obtain minimum weight frames
by selecting suitable sections from a standard set of steel sections such as American Institute of Steel Construction (AISC)
wide-flange (W) shapes. Strength constraints of AISC load and resistance factor design specification and displacement constraints
were imposed on frames. The effectiveness and robustness of harmony search algorithm, in comparison with genetic algorithm
and ant colony optimization-based methods, were verified using three steel frames. The comparisons showed that the harmony
search algorithm yielded lighter designs.
Many optimization problems in various fields have been solved using diverse optimization al gorithms. Traditional optimization techniques such as linear programming (LP), non-linear programming (NLP), and dynamic program ming (DP) have had major roles in solving these problems. However, their drawbacks generate demand for other types of algorithms, such as heuristic optimization approaches (simulated annealing, tabu search, and evolutionary algo rithms). However, there are still some possibili ties of devising new heuristic algorithms based on analogies with natural or artificial phenom ena. A new heuristic algorithm, mimicking the improvisation of music players, has been devel oped and named Harmony Search (HS). The performance of the algorithm is illustrated with a traveling salesman problem (TSP), a specific academic optimization problem, and a least-cost pipe network design problem.
The geometrical complexity available through additive manufacturing processes requires new tools to help designers maximise its advantages. A termite colony can construct highly complex nests that are optimised for thermoregulation and ventilation. The simple individual behaviour of these termites leads to highly intelligent colony behaviour, allowing nests to be simultaneously designed, optimised and produced. By mimicking termite behaviour, this research has led to a new design methodology using multi-agent algorithms that simultaneously design, structurally optimise and appraise the manufacturability of parts produced by additive manufacturing. A case study demonstrates the generative design of lightweight parts using the multi-agent system.
Site layout planning is often performed on construction sites to find the best arrangement of temporary facilities so that transportation distances of on-site personnel and equipment are minimized. It could be achieved by creating dynamic layout models, which capture the changing requirements of construction sites. However, formulating such models is extremely tedious because it requires much manual data input and changes to design and construction plans are manually updated by layout planners. This study presents an automated framework of creating dynamic site layout models by utilizing information from BIM. The A∗algorithm is used in conjunction with genetic algorithms to develop an optimization framework that considers the actual travel paths of on-site personnel and equipment. To address the space limitation on site, our model optimizes the dimensions of facilities and also considers interior storage within buildings under construction. A case example is demonstrated to validate this framework and shows a 13.5% reduction in total travel distance compared with conventional methods.
This paper develops a mathematical formulation to model and optimise site facility locations inside a construction site for a construction project's different stages. The existence and dimensions of a construction project's available locations and site facilities can be varied across the construction stages. Without proper planning, unnecessary facility relocations may be required in each construction stage, resulting in a higher construction cost and longer construction time due to the need to dismantle and set up site facilities. Site layout plans should be optimised using a multiple-stage model to avoid unnecessary changes to facility settings across construction stages, improving efficiency. The proposed site layout problem with multiple construction stages is formulated as a binary-mixed-integer-linear programme, which can be solved by a standard branch-and-bound algorithm using the commercial software package LINGO. The mathematical objective function established in the solution process aims to minimise the total cost, which consists of the material transportation cost between the relevant site facilities and the dismantling, setup and relocation costs for all of the involved site facilities in each construction stage. Numerical examples using the proposed mathematical model to optimise different site layout settings for a construction site are given, including (1) a reference site layout plan using the conventional static single-stage approach, (2) a multiple-stage construction site layout plan and (3) a multiple-stage site layout plan with additional safety design considerations.
Recent increases in the number of irregularly shaped tall buildings have created a need for more applicable formwork methods and automated support for formwork layout planning, which has mainly depended on heuristic approaches based on the intuitive judgment of experienced engineers. This study proposes a new table formwork method integrated with a systematic layout planning approach for tall building construction. Adjustable subunits of the formwork cope with diverse building shapes and the software-based mathematical model helps practitioners make useful layouts for the method with minimal time and effort. In a case study, the proposed layout planning model offered lower costs and improved work efficiency in less time than the heuristic approach. Supported by the planning model, our advanced formwork method showed a 15.5% increase in covered area of irregularly shaped building floors and a 23.9% decrease in material costs compared with existing table formwork methods.
Gene selection, which is a well-known NP-hard problem, is a challenging task that has been the subject of a large amount of research, especially in relation to classification tasks. This problem addresses the identification of the smallest possible set of genes that could achieve good predictive performance. Many gene selection algorithms have been proposed; however, because the search space increases exponentially with the number of genes, finding the best possible approach for a solution that would limit the search space is crucial. Metaheuristic approaches have the ability to discover a promising area without exploring the whole solution space. Hence, we propose a new method that hybridises the Harmony Search Algorithm (HSA) and the Markov Blanket (MB), called HSA-MB, for gene selection in classification problems. In this proposed approach, the HSA (as a wrapper approach) improvises a new harmony that is passed to the MB (treated as a filter approach) for further improvement. The addition and deletion of operators based on gene ranking information is used in the MB algorithm to further improve the harmony and to fine-tune the search space. The HSA-MB algorithm method works especially well on selected genes with higher correlation coefficients based on symmetrical uncertainty. Ten microarray datasets were experimented on, and the results demonstrate that the HSA-MB has a performance that is comparable to state-of-the-art approaches. HSA-MB yields very small sets of genes while preserving the classification accuracy. The results suggest that HSA-MB has a high potential for being an alternative method of gene selection when applied to microarray data and can be of benefit in clinical practice.
The task of positioning temporary facilities on a construction site has long been recognized as a factor of great influence on the cost of projects. This paper proposes the use of a recently developed harmony search (HS) algorithm to solve the problem of assigning a set of predetermined facilities to a set of preallocated locations within a construction site. Experiments with different parameter settings were conducted, and an alternative approach was used with a modified HS algorithm to overcome shortcomings of the original method. The proposed algorithm shows a rapid convergence to an optimum solution during the early stages of algorithm progress. In addition, comparisons with different variations of the HS algorithm and genetic algorithm (GA) are presented to demonstrate the efficiency of the proposed method and HS methodology in solving facility layout problems.Le positionnement des installations temporaires sur un site de construction a depuis longtemps été un facteur influençant beaucoup le coût des projets. Le présent article propose l'utilisation d'un algorithme de recherche métaheuristique mis au point récemment afin de résoudre le problème d'assignation d'un ensemble d'installations prédéterminées à un ensemble d'endroits pré-assignés au site de construction. L'expérimentation de divers réglages de paramètres a permis d'utiliser une approche alternative comportant un algorithme de recherche métaheuristique modifié afin de surmonter les lacunes de la méthode initiale. L'algorithme proposé montre une convergence rapide vers des solutions optimales dès les premières étapes de l'algorithme. Sont également présentées des comparaisons aux diverses variations de l'algorithme de recherche métaheuristique et à l'algorithme génétique afin de démontrer l'efficacité de la méthode proposée et de la méthode de recherche métaheuristique pour résoudre les problèmes de disposition des installations.
A newly developed heuristic algorithm, Harmony Search, is applied to the parameter estimation problem of the nonlinear Muskingum model. Harmony Search found better values of parameters in the nonlinear Muskingum model than five other methods including another heuristic method, genetic algorithm, in terms of SSQ (the sum of the square of the deviations between the observed and routed outflows), SAD (the sum of the absolute value of the deviations between the observed and routed outflows), DPO (deviations of peak of routed and actual flows), and DPOT (deviations of peak time of routed and actual outflow). Harmony Search also has the advantage that it does not require the process of assuming the initial values of design parameters. The sensitivity analysis of Harmony Memory Considering Rate showed that relatively large values of Harmony Memory Considering Rate makes the Harmony Search converge to a better solution.
Construction site layout planning (CSLP) is a dynamic multi-objective optimization (MOO) problem as there are different facilities employed in the different construction phases of a construction project. In this study, a new method using continuous dynamic searching scheme to guide the max-min ant system (MMAS) algorithm, which is one of the ant colony optimization (ACO) algorithms, to solve the dynamic CSLP problem under the two congruent objective functions of minimizing safety concerns and reducing construction cost is proposed. Using weighted sum method the MOO problem can be solved by the proposed MMAS method. An office building case was used to verify the capability of the proposed method to solve dynamic CSLP problem and the results are promising. The approach could be benchmarked by researchers using other advanced optimization algorithms to solve the same problem or expand the applications to other fields.
Most structural optimization methods are based on mathematical algorithms that require substantial gradient information. The selection of the starting values is also important to ensure that the algorithm converges to the global optimum. This paper describes a new structural optimization method based on the harmony search (HS) meta-heuristic algorithm, which was conceptualized using the musical process of searching for a perfect state of harmony. The HS algorithm does not require initial values and uses a random search instead of a gradient search, so derivative information is unnecessary. Various truss examples with fixed geometries are presented to demonstrate the effectiveness and robustness of the new method. The results indicate that the new technique is a powerful search and optimization method for solving structural engineering problems compared to conventional mathematical methods or genetic algorithm-based approaches.
This paper develops an Improved harmony search (IHS) algorithm for solving optimization problems. IHS employs a novel method for generating new solution vectors that enhances accuracy and convergence rate of harmony search (HS) algorithm. In this paper the impacts of constant parameters on harmony search algorithm are discussed and a strategy for tuning these parameters is presented. The IHS algorithm has been successfully applied to various benchmarking and standard engineering optimization problems. Numerical results reveal that the proposed algorithm can find better solutions when compared to HS and other heuristic or deterministic methods and is a powerful search algorithm for various engineering optimization problems.
Most engineering optimization algorithms are based on numerical linear and nonlinear programming methods that require substantial gradient information and usually seek to improve the solution in the neighborhood of a starting point. These algorithms, however, reveal a limited approach to complicated real-world optimization problems. If there is more than one local optimum in the problem, the result may depend on the selection of an initial point, and the obtained optimal solution may not necessarily be the global optimum. This paper describes a new harmony search (HS) meta-heuristic algorithm-based approach for engineering optimization problems with continuous design variables. This recently developed HS algorithm is conceptualized using the musical process of searching for a perfect state of harmony. It uses a stochastic random search instead of a gradient search so that derivative information is unnecessary. Various engineering optimization problems, including mathematical function minimization and structural engineering optimization problems, are presented to demonstrate the effectiveness and robustness of the HS algorithm. The results indicate that the proposed approach is a powerful search and optimization technique that may yield better solutions to engineering problems than those obtained using current algorithms.
The Harmony Search (HS) algorithm is a population-based metaheuristic optimisation algorithm. This algorithm is inspired by the music improvisation process in which the musician searches for harmony and continues to polish the pitches to obtain a better harmony. Although several variants of the HS algorithm have been proposed, their effectiveness in dealing with diverse problems is still unsatisfactory. The performances of these variants mainly depend on the selection of different parameters of the algorithm. In this paper, a new variant of the HS algorithm is proposed that maintains a proper balance between diversification and intensification throughout the search process by automatically selecting the proper pitch adjustment strategy based on its Harmony Memory. However, the performance of the proposed Intelligent Tuned Harmony Search (ITHS) algorithm is influenced by other parameters, such as the Harmony Memory Size (HMS) and the Harmony Memory Considering Rate (HMCR). The effects that varying these parameters have on the performance of the ITHS algorithm is also analysed in detail. The performance of the proposed ITHS algorithm is investigated and compared with eight state-of-the-art HS variants over 17 benchmark functions. Furthermore, to investigate the robustness of the proposed algorithm at higher dimensions, a scalability study is also performed. Finally, the numerical results obtained reflect the superiority of the proposed ITHS algorithm in terms of accuracy, convergence speed, and robustness when compared with other state-of-the-art HS variants.
The development of automatic module for formwork layout using the BIM
- C Lee
- S Ham
- G Lee
C. Lee, S. Ham, G. Lee, The development of automatic module for formwork layout using
the BIM, International Conference on Construction Engineering and Management, vol. 3,
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The Process for Development of the Optimum Layout Model in Slab Formwork of High-rise Building Construction
- M Cha
- T Kim
- H Cho
- K.-I Kang
M. Cha, T. Kim, H. Cho, K.-I. Kang, The Process for Development of the Optimum Layout
Model in Slab Formwork of High-rise Building Construction, 2011 Spring Conference vol.
11, The Korea Institute of Building Construction, 2011, pp. 171-172.
Advanced system formwork and construction planning model for tall building construction, Doctoral Dissertation Paper
- T Kim
T. Kim, Advanced system formwork and construction planning model for tall building
construction, Doctoral Dissertation Paper, Korea University, Seoul, Korea, 2013.
Doka formwork solution
- Dokacad
DokaCad, Doka formwork solution, https://www.doka.com/en/solutions/services/tipos/
tipos-planning-software/DokaCAD8-software-formwork-planning.