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Analysis of Embodied Energy and Carbon Emission of a Single Story Rural Area Structure
(Gazi Univ, 2023) Erzurum, Tugba; Bettemir, Onder Halis
Determining and analyzing the adverse consequences of construction works on the environment is an important research area. The necessity of execution of a large number of work items for the construction of a building and the large number of building material options make it difficult to conduct embodied energy and carbon emission analyzes of building constructions. In this study, a framework system is developed to overcome the mentioned difficulties. Construction items of a typical single -story building that can be built in the rural region are arranged and different construction options are generated for the construction items. The amounts of material and construction equipment requirements for the unit construction item of all construction options are computed. Semantic relationships between the building elements and the construction alternatives are established so that the quantity values that may vary according to the selected work item can be calculated exactly. Cost, embodied energy and carbon emissions caused by the construction of the building are calculated by matching the quantity values with the unit construction item definitions. Moreover, the heat loss calculations of the building are carried out according to TS 825 and the energy consumption, carbon emission and cost that will occur as a result of the utilization of wood, coal, electric stove and air conditioner options as heating source during its 50 years of life cycle are calculated. In order to examine the effects of construction items on the embodied energy, carbon emission and cost, Monte Carlo simulation is implemented by forming the building with random selections for each construction item among the defined construction options with equal probability of selection. At the end of the simulation the total embodied energy, carbon emission and cost of both the construction and the utilization phases of the structure are calculated. In this manner, the average embodied energy, carbon emission and cost effect of each of the construction items on the structure are determined. Prepared embodied energy and carbon emission quantities of the construction items and the analysis results presented within this study have the potential to be beneficial to the researchers studying on green buildings.
Cost and duration estimation of autonomous grading algorithm by simulation
(Yildiz Technical Univ, 2024) Bettemir, Onder Halis
Estimation of cost and duration of grading a particular area provides important information for contractors and construction machine manufacturers. In this study, cost and duration of excavation by dozer is estimated by simulating the movements of the dozer. Specifications of the dozer, soil conditions and site conditions are defined to the simulator. The simulation considers tire penetration, rolling, grade, hauling, as well as cutting resistances and estimates the necessary force to be applied. The simulation implements an autonomous grading algorithm established for electric powered dozers which starts grading from a local highest point to prevent uphill excavation and hauling. The algorithm determines the necessary maneuvers to reach local highest point, excavate or haul the earth pile to the dump area. The simulation runs until the objected elevation is obtained at each portion of the excavation site. The simulator calculates the consumed energy, time, and total cost of the excavation. The excavations of 30x45 square meter area by one existing electric dozer and five updated versions of it are simulated. The simulation of the excavation is computed in 23 seconds for the smallest and 10 seconds for the largest dozer. The cost of grading and pushing the excavated material at most 20 meters away is estimated as less than 5 cents/m3 for the lead-acid battery powered dozer and 8 cents/m3 in the average for the lithium-ion battery powered dozers. The simulation revealed that electric powered dozers have less unit excavation cost than diesel powered ones, also larger dozers consumes less energy than the smaller ones. The developed simulation technique is implemented without any numerical errors and the technique can be beneficial for the construction machine manufacturers to optimize their designs and for the contractors to select the most suitable construction machine among the present alternatives.
Detection of Railway Track from Image by Heuristic Method
(Ieee, 2015) Bettemir, Onder Halis
Defects on the railway track occur due to the abrasive effects of time and usage. As the magnitude of the defects increases, uncomfortable travel appears. If the defects progress further they may cause derailment of the train. Detection of the defects are performed by manual inspection of the track, which cause ignorance of some of the defects. In this study a heuristic algorithm, which detects railway track from the images acquired by unmanned vehicle, is developed. Rails and sleepers of the railway track is detected with high accuracy from the images acquired in nadir direction. Images are de-noised by Gauss filter and edges are detected by Prewitt Edge Detection algorithm. By considering the geometric properties of the railway track and the brightness values of the edges, the Heuristic algorithm decides on which edges belong to railway track. In this study, inspection of railways is proposed by the images acquired by unmanned aerial vehicles and the automated detection of railway elements are realized as the first step of the railway inspection.
Determination of Thermal Bridge of the Buildings from Infrared Images
(Gazi Univ, 2023) Bettemir, Onder Halis
Vast majority of the existing buildings in Turkiye are not inspected for thermal insulation quality during the construction process therefore, thermal insulation performance of the existing buildings cannot be known. Measuring the thermal insulation performance of the buildings by scraping the plaster and examining the heat insulation material is not a viable solution when the size of the building stock of Turkiye is considered. In this study, detection of thermal bridges of the buildings by processing the thermal images of the buildings is proposed. The method is based on the binarization of the thermal image by the classification of the building elements as heat loss element or no heat loss element by analyzing the thermal image of the building. Global threshold methods and adaptive local threshold methods applied for binarization. All of the implemented methods require a threshold value for the classification. Determining a valid threshold value for all images is not possible therefore the threshold value is determined by the Otsu algorithm. Threshold determination process is executed both on the thermal image and the edge image. Obtained threshold values are implemented on the thermal images and the edge images. Local edge detection algorithms derived from the literature are compared by examining five thermal images and the comparison revealed that the Modified II Frei-Chen and Second-order Laplace operator provided the most suitable result. The case studies revealed that the thermal insulation performance of the existing building stock can be determined quickly, economically and reliably by implementing the proposed method.
Development of ontological algorithms for exact QTO of reinforced concrete construction items
(Elsevier Science Inc, 2024) Ergen, Faruk; Bettemir, Onder Halis
Building Information Modeling (BIM) provides significant benefits to the construction industry throughout the project management process. However, state-of-the-art BIM software provides erroneous quantity take -off (QTO) results above the negligible margin. In this study, QTO calculation algorithms have been developed for rough construction and implemented on BIM software to solve the stated problem. The developed QTO algorithms establish semantic relations and search the neighborhood of the structural elements to detect the intersecting structural elements. Amount of intersection is calculated by the dimensions and the locations of the intersecting structural elements. Exact length and spacing of the rebar and stirrups are calculated by considering the created semantic relationships. QTO of formwork is accurately calculated by considering the voids of the QTO computations which are obtained from the constructed semantic relationships by investigating the column -beam, slabbeam, and slab -column contact areas. Furthermore, the construction type of the scaffolding for the formwork is determined by considering both the dimensions of the structure and the established semantic relations. The developed algorithms are executed on BIM capable software and tested in four case studies with special conditions. The comparison with manual condition revealed that the proposed algorithms provided exact results. The semantic QTO algorithms developed in this study have the potential to be useful for BIM software developers.
ERROR ANALYSIS OF VISUAL ODOMETRY FOR A SMALL SIZE UNMANNED AERIAL VEHICLE
(Copernicus Gesellschaft Mbh, 2024) Bettemir, Onder Halis
Usage of small size Unmanned Aerial Vehicle (UAV) with autonomous flight capability became widespread at both civil and military applications because of its low costs and ease of use. However, inertial or GPS based positioning and orientation sensors can be disabled at battlefields and the UAV losses its path in a short time. Visual odometry becomes a solution for the aforementioned hassle. Real-time detection of ground control points, matching the same control points at the stereo pair images and correcting the position and orientation data with least square adjustment are the challenges of visual odometry. In this study, error analysis of position and orientation of a UAV flying through mountainous region which cannot obtain any augmenting data for position and orientation is conducted by error propagation law. The flight of UAV is simulated with exact initial position and orientation data. Optic images of ground obtained by nadir directed camera are georeferenced using the digital elevation model of the region, interior and exterior camera parameters. The digital elevation model is used to correct the relief displacement. The stereo-pair image is obtained when the UAV flies 200 m and image coordinates of the common control points are detected by colinearity equations. Position and orientation of UAV is corrected by least square adjustment and the process is repeated for each obtained image acquired at 200 m interval. The analysis revealed that the precisions of horizontal and vertical positioning becomes 75 and 200 meter, respectively. The precision of roll angle becomes worse than 0.5 degree, while the precisions of pitch and yaw angle are estimate to be better that 0.1 degree.
Fast Converging Moment Distribution Algorithm for Structural Analysis on Smartphones
(Turkish Chamber Civil Engineers, 2017) Bettemir, Onder Halis
Throughout the construction, unforeseen loading combinations on the scaffolding and the temporary facilities may occur. Since the site engineers have to take quick decisions, they make intuitive decisions, which may cause failures. In this study, moment distribution method based structural algorithm, which can run on handheld devices, is proposed to assist site engineers. Conventional moment distribution method is improved to solve the frames that are free to sidesway and settlement at once. As a result, the proposed algorithm can be efficiently implemented on hand-held devices, which have limited memory and processing power. Whereby, the site engineer can analyze any construction phase real-time and immediately take sound decisions.
Hybrid Genetic Algorithm with Simulated Annealing for Resource-Constrained Project Scheduling
(Asce-Amer Soc Civil Engineers, 2015) Bettemir, Onder Halis; Sonmez, Rifat
Resource-constrained project scheduling problem (RCPSP) is a very important optimization problem in construction project management. Despite the importance of the RCPSP in project scheduling and management, commercial project management software provides very limited capabilities for the RCPSP. In this paper, a hybrid strategy based on genetic algorithms, and simulated annealing is presented for the RCPSP. The strategy aims to integrate parallel search ability of genetic algorithms with fine tuning capabilities of the simulated annealing technique to achieve an efficient algorithm for the RCPSP. The proposed strategy was tested using benchmark test problems and best solutions of the state-of-the-art algorithms. A sole genetic algorithm, and seven heuristics of project management software were also included in the computational experiments. Computational results show that the proposed hybrid strategy improves convergence of sole genetic algorithm and provides a competitive alternative for the RCPSP. The computational experiments also reveal the limitations of the project management software for resource-constrained project scheduling. (C) 2014 American Society of Civil Engineers.
A Memetic Algorithm for the Solution of the Resource Leveling Problem
(Mdpi, 2023) Iranagh, Mehdi; Sonmez, Rifat; Atan, Tankut; Uysal, Furkan; Bettemir, Onder Halis
In this paper, we present a novel memetic algorithm (MA) for the solution of the resource leveling problem (RLP). The evolutionary framework of the MA is based on integration of a genetic algorithm and simulated annealing methods along with a resource leveling heuristic. The main objective of the proposed algorithm is to integrate complementary strengths of different optimization methods and incorporate the individual learning as a separate process for achieving a successful optimization method for the RLP. The performance of the MA is compared with the state-of-the-art leveling methods. For small instances up to 30 activities, mixed-integer linear models are presented for two leveling metrics to provide a basis for performance evaluation. The computational results indicate that the new integrated framework of the MA outperforms the state-of-the-art leveling heuristics and meta-heuristics and provides a successful method for the RLP. The limitations of popular commercial project management software are also illustrated along with the improvements achieved by the MA to reveal potential contributions of the proposed integrated framework in practice.
MINIMUM-COST DESIGN OF WATER DISTRIBUTION LINE WITH DIFFERENTIAL EVOLUTION ALGORITHM
(Yildiz Technical Univ, 2017) Ozdemir, Ozgur; Bettemir, Onder Halis; Firat, Mahmut
In this study, a design approach which minimizes the construction and operation costs of water distribution line with differential evolution algorithm is proposed. Digital Elevation Model, monthly water demand, technical codes and unit prices of construction items are defined to optimization module in order to realize the cost optimum design. Pump, pipe diameter and type are defined as design variables. Construction cost of the design is computed by the unit price of the cost items. To determine the annual operation costs, flow is computed according to the Darcy-Weisbach equations. Pumping duration is determined and annual energy cost is computed. Net present value of the investment is computed by considering the time value of the money which is evaluated by the debt interest rate. Minimum-cost design alternative is searched by differential evolution algorithm. As a result, the best pump and pipe combination is obtained and summation of the construction and operation costs are minimized. Minimization of the sum of the investment and operation costs may provide the opportunity of significant improvement in the budget of the municipalities in the long run. Consequently, implementation of the proposed design approach will be beneficial for the local authorities.
Network Analysis Algorithm for the Solution of Discrete Time-Cost Trade-off Problem
(Korean Society Of Civil Engineers-Ksce, 2017) Bettemir, Onder Halis; Birgonul, M. Talat
Optimum solution of time-cost trade-off problem has significant importance since it provides the highest profit opportunity. For this reason, exact, heuristic, and meta-heuristic algorithms are adapted to obtain the optimum or near-optimum solution. However, heuristic algorithms may not always converge into the global optimum, while meta-heuristic algorithms require significant computation to converge into global optimum and exact methods are complex for construction planners to implement. Therefore, minimum cost-slope based fast converging network analysis algorithm, which provides optimum or near-optimum solutions, is proposed for discrete time-cost trade-off problem. The algorithm searches the global optimum through the feasible crashing options. Number of feasible crashing options increase tremendously in large projects. Therefore, an elimination algorithm is embedded to reduce the number of crashing options. The crashing option with the lowest unit crashing cost is executed and global optimum is searched by stepwise crashing. Tests on 18 and 63-Activity projects revealed that the network analysis algorithm converges to optimum or near-optimum solution by only one percent of the computational demand of meta-heuristic algorithms. Consequently, the proposed heuristic algorithm is a convenient optimization method for the solution of time-cost trade-off problem.
QUALITY AND SAFETY ASSURANCE OF RAILWAY TRACKS BY UAV
(Amer Soc Mechanical Engineers, 2016) Bettemir, Onder Halis
Safety assurance of railway tracks is an important task because defects on the railway track may cause trains to be derailed. Unfortunately, there are many fatal train crashes reported in Turkey, Spain and India caused by derailment of the trains. Besides the fatalities, derailment of the trains causes significant economic losses, delay of the timetables and discomfort. Manually investigating the railway tracks are substantially time consuming and expensive. In addition to this, it is human dependent so that the task is prone to error, which may end up without noticing important defects. In this study, a robust and economical method, which automates the investigation of railway tracks, is proposed. The proposed method scans the railway track by a high-resolution optic camera mounted on an UAV. Obtained optic images of the railway track are georeferenced by automatically extracting the Ground Control Points (GCP). The railway track is extracted from the optic image by edge detection. Afterward, any defect on the railway track such as missing bolt or damage on the sleepers and any impropriety of ballasts can be detected by performing image analysis techniques. Advantages of the optic system are its lightweight, higher georeferencing accuracy, and low power consumption. Sony HX300 DSLR camera with 20.4 MP resolution is calibrated on the ground and optical images are obtained at similar imaging geometry. For this reason, flight altitude is fixed as 12 foot above the railway track. The optical camera is mounted on quadcopter, which has 6 kg of maximum take-off weight. The system is tested in Pittsburgh and satisfactory initial test results are obtained. Consequently, site tests showed that the proposed robust and economic system is a good candidate to be implemented for monitoring the railway tracks.
Recommendations on the solution of accommodation problem and recovery after destructive earthquakes
(Inderscience Enterprises Ltd, 2016) Bettemir, Onder Halis
Inexpensive, environmentally friendly and pleasing solutions for the temporary accommodation requirements of victims have to be provided after a destructive earthquake. In this study, funding options to expedite the repairment process and the consequences of minimisation of temporary housing construction are examined and a disaster management study is proposed. Temporary accommodation demand is estimated by damage assessment reports of previous earthquakes, and cost of temporary accommodation facilities is estimated by unit price indexes. Construction of temporary housing is avoided by expediting the repairment of the buildings, providing rent-aids and tent camps. Minimisation of temporary housing reduces the recovery cost and harmful effects on the environment, and increases user satisfaction. Moreover, resources are mainly allocated for the repairment tasks to expedite the recovery process. Recommended disaster management strategy is simulated on the 2011 Ercis-Van earthquakes. The simulation revealed that the proposed method had significant savings in terms of cost, duration and environmental impact.
Scheduling, Management and Optimization of Construction Process
(Turkish Chamber Civil Engineers, 2022) Bettemir, Onder Halis; Bulak, Omer Faruk
In this study, computation of quantity take-off, man hour and material requirements; determination of activity durations and crew sizes; and preparation of construction schedule related with the construction of a building are formulated by associating them with the geometry of the building, the construction items, and the available resources. Obtained quantity take-off values is joined with the item codes of the unit price analysis of Ministry of Environment, Urbanization and Climate Change of Republic of Tiirkiye and after this operation quantities of material, workmanship, and machinery requirements are computed by the corresponding unit price analysis data. Line-of-Balance schedule is prepared by considering the physical and logical constraints between the activities and construction duration is estimated. Construction project can be executed by different subcontractors which may have diverse workdays and the developed application computes the project duration in terms of calendar days by considering the different work calendars of the construction crews. Moreover work efficiency is estimated by considering the effects of seasonal conditions, and month Ramadan Optimization of construction schedule is executed by Genetic Algorithm with Simulated Annealing (GASA) according to the restrictions on the construction duration and the maximum available labor as well as the delay penalty. In this study resource constrained project scheduling and time cost trade-off problems are formulated by taking the possibilities of the project stakeholders may have different workdays and the job efficiencies may deviate according to the seasonal conditions into account which makes preparation of construction schedules considering more factors possible. This approach provides fast implementation of efficient construction management techniques.
Sensitivity Analysis to Estimate the Positional Accuracy of a Small Size Unmanned Aerial Vehicle
(Ieee, 2023) Bettemir, Onder Halis
Small size Unmanned Aerial Vehicles (UAV) are utilized at the military operations since they cannot be detected by RADAR or air defense systems easily. In this study suitability and functionality of small size and low cost UAVs are examined. The examination considers the case where the positioning sensors and the remote control system of the UAV are out of order by the signal breakers or jammers. The position and the attitude of the UAV are estimated by resection without using ground control points. The autonomous flight of the UAV is navigated by Simultaneous Localization and Mapping (SLAM) based algorithm. The accuracies of the position and attitude of the UAV is estimated by implementing the variance propagation law for the georeferencing of the images taken by the on board camera of the UAV. The sensitivity analysis is conducted for the situation where the UAV flies through a mountainous region. The results of this study can be useful for the decision makers to assess the success rate of the mission conducted by a small scale UAV.
Simplified Solution of Time-Cost Trade-off Problem for Building Constructions by Linear Scheduling
(Jordan Univ Science & Technology, 2023) Bettemir, Onder Halis; Yucel, Tugay
Time-cost trade-off is an important optimization problem for contractors, because its optimum solution minimizes the total project cost. Formation of the time-cost trade-off problem causes an important workload, since the problem requires preparation of different construction cost and duration alternatives of the activities. Previous studies focused on the optimum solution of the problem and ignored the difficulties of the preparation of the different construction alternatives for the activities, which is a very difficult task for contractors. In this study, the creation of construction alternatives consisting of different time and cost values is automated. Quantity take-off of construction items is computed by user-defined dimensions of structural elements. Workmanship and material requirements are computed by pre-defined job descriptions and quantity take-off values. Different construction alternatives are formed by assigning different crew sizes and the corresponding construction durations are computed by estimating the job efficiency of the crew by regression models derived from the literature. Precedence relationships of the main construction items are pre-defined and the construction schedule is formed by a line of balance in terms of work days. The problem is optimized by a genetic algorithm the parameters of which are fine-tuned by experimental design. The developed approach is implemented on a spreadsheet application and the total optimization process including data entry is completed in one and a half hour on a desktop computer with i5 CPU. This study contributes to relevant literature by proposing a systematic approach for the formation of construction alternatives of the time-cost trade-off problem. The proposed approach can be beneficial for contractors and project managers to form and solve the time-cost trade-off problem with minimum endeavor and cost.
Simulation of Autonomous Grading of Lunar Surface
(Ieee, 2023) Bettemir, Onder Halis
Lunar missions of space agencies aim to set up permanent facilities on the surface of the Moon. Vast majority of the construction activities should be executed as unmanned because of the unsuitable habitat conditions of the Moon. In this study autonomous grading of Moon surface by an electric powered small scale dozer is examined. An autonomous grading algorithm is implemented for the grading task of a small region which is large enough to be an artifact base on the Moon. The autonomous grading algorithm takes rolling, tire penetration, grade, hauling of the earth pile, and cutting resistances into account. Gravity of the Moon is lower than the gravity of the Earth which causes skidding of the tires. The grading algorithm also takes the maximum applicable force and adjusts the earth pile in front of the dozer blade. Lead-acid battery powered and lithium-ion battery powered dozers are simulated in order to detect the efficiency of the construction machine. The simulation divides the excavation area into equal sized grids and computes the consumed time to work on each grid. The required force and the consumed energy are computed for each grid. The simulation iteratively updates the elevations of the grids and the iteration continues until the elevations of the grids become equal to the required elevation. Simulation revealed that lead-acid battery powered dozer is more suitable for the earthwork tasks on the Moon.
Solution of discrete time-cost trade-off problem with adaptive search domain
(Emerald Group Publishing Ltd, 2023) Bettemir, Onder Halis; Birgonul, M. Talat
PurposeExact solution of time-cost trade-off problem (TCTP) by the state-of-the-art meta-heuristic algorithms can be obtained for small- and medium-scale problems, while satisfactory results cannot be obtained for large construction projects. In this study, a hybrid heuristic meta-heuristic algorithm that adapts the search domain is developed to solve the large-scale discrete TCTP more efficiently.Design/methodology/approachMinimum cost slope-based heuristic network analysis algorithm (NAA), which eliminates the unfeasible search domain, is embedded into differential evolution meta-heuristic algorithm. Heuristic NAA narrows the search domain at the initial phase of the optimization. Moreover, activities with float durations higher than the predetermined threshold value are eliminated and then the meta-heuristic algorithm starts and searches the global optimum through the narrowed search space. However, narrowing the search space may increase the probability of obtaining a local optimum. Therefore, adaptive search domain approach is employed to make reintroduction of the eliminated activities to the design variable set possible, which reduces the possibility of converging into local minima.FindingsThe developed algorithm is compared with plain meta-heuristic algorithm with two separate analyses. In the first analysis, both algorithms have the same computational demand, and in the latter analysis, the meta-heuristic algorithm has fivefold computational demand. The tests on case study problems reveal that the developed algorithm presents lower total project costs according to the dependent t-test for paired samples with alpha = 0.0005.Research limitations/implicationsIn this study, TCTP is solved without considering quality or restrictions on the resources.Originality/valueThe proposed method enables to adapt the number of parameters, that is, the search domain and provides the opportunity of obtaining significant improvements on the meta-heuristic algorithms for other engineering optimization problems, which is the theoretical contribution of this study. The proposed approach reduces the total construction cost of the large-scale projects, which can be the practical benefit of this study.

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