İnşaat Projelerinde Zaman Maliyet Ödünleşim Problemi: Örnek Olay Analizi

Year 2020, Issue: 19, 460 - 465, 31.08.2020

Mehmet Nurettin Uğural

https://doi.org/10.31590/ejosat.726891

Cited By: 1

Abstract

Globalleşen dünyada artan rekabet koşullarıyla birlikte inşaat projelerinin gerek zaman gerekse maliyet olarak optimize edilmesi kaçınılmaz bir hal almıştır. Bu ortamda proje yöneticisinin karşı karşıya olduğu en önemli zorluklardan biri, projeye ayrılan zaman ve finansal kaynak kısıtları içerisinde istenilen kalite standartlarına göre projenin yapılabilirliğine karar vermek ve sonrasında tamamlanmasını sağlamaktır. Günümüzde proje yöneticileri sürekli bir zaman ve maliyet indirgenmesi baskısıyla karşı karşıyadır. Bu noktada her bir proje için zaman ve maliyet ödünleşiminin nasıl yapılacağı ve hangi türden bir model geliştirileceği proje yöneticilerinin üzerinde çalıştığı en ciddi problemlerden birisi olarak karşımıza çıkar. Bu çalışmanın amacı örnek olarak ele alınan proje üzerinde zaman-maliyet ödünleşim analizi ile proje süresinin nasıl indirgendiğini göstermektir. Çalışmada İlk olarak hızlandırma sürelerini ve maliyetlerini bulmak için sezgisel bir yöntem olan kritik yol yöntemi (CPM) kullanılarak kritik yol ve bu yol üzerindeki kritik aktiviteler belirlenmiştir. Projede yer alan faaliyetlerin sürelerinin deterministik olduğu öngörülmüştür. Kritik yol üzerindeki faaliyetlerin hızlandırma süreleri sezgisel yöntemle tespit edildikten sonra amaç fonksiyonun belirlenmesi için bu faaliyetlerin maliyet eğimi hesaplanmıştır. Optimizasyon modeli oluşturarak zaman ve maliyet parametreleri arasındaki ilişkiyi tanımlayabilmek için regresyon analizi uygulanmış ve oluşturulan problem MATLAB 9,7 programı ile çözülmüştür. Analiz sonucunda projenin en uygun 741 lira bütçe ve 2 hafta hızlandırmayla toplam 17 haftada tamamlanabileceği görülmüştür.

Keywords

İnşaat proje yönetimi, kritik yol metodu, zaman maliyet ödünleşimi, hızlandırma

Time-Cost Trade-Off Analysis in a Construction Projects: Case Study

Abstract

This is a very difficult challenge for project managers in today's competitive world to complete a project within time and budget. In this environment, one of the most important challenges faced by the project manager is to decide on the feasibility of the project by the desired quality standards within the time frame and the financial resources allocated to the project. The cost and time of the project always play a vital role in the decision of the construction projects. Project managers today are faced with constant pressures in terms of time and cost management. At this point, it is one of the most serious problems for project managers to work on how to make time and cost trade-offs and what kind of models to develop. The objective of the time-cost trade-off analysis is to reduce the duration of the original project at the lowest possible total cost. The main purpose of this study is to demonstrate, in a simply and understandable way, how the time of the project is reduced by the time-cost trade-off analysis of the project. Secondly, to determine the optimum point between time and cost. In this paper, critical path method is used to find out the duration and the cost of the crashing with heuristic method. The duration of the project activities is predicted to be deterministic. Regression analysis is carried out to identify the relationship between time and cost in order to formulate a quadratic model. The analysis reveals that through proper scheduling of all activities, the project can be completed within 13 weeks from estimated19 weeks. The problem is then solved by the MATLAB program, which has an optimum cost of at least 741.000 TL. with a duration of 17 to weeks.

Keywords

Construction Project Management, Critical Path, Time-Cost Trade-Off Analysis, Crashing

References

• Arditi, D., Tokdemir, O. B., and Suh, K. (2002) “Challenges in line-of-balance scheduling.” J. of Construction Engineering and Management, ASCE, Vol. 128, No.1, pp. 545–556.
• Azaron, A., Perkgoz, C., and Sakawa, M., (2005) A genetic algorithm approach for time-cost trade-off in PERT networks. Applied Mathematics And Computation, 168, 1317-1339
• Aziz, R. F. (2013) RPERT: Repetitive-Projects Evaluation and Review Technique. Alexandria Engineering Journal, 53, 81-93. Ballesteros-Pérez, P., Larsen, G. and González-Cruz, M. (2018) Do Projects Really End Late? On the Shortcomings of The Classical Scheduling Techniques. Journal of Technology and Science Education, 8, 17-33.
• Bettemir, O.H., and Birgonul, T. (2016) "Network analysis algorithm for the solution of discrete time-cost trade-off problem", KSCE J. Civ. Eng., 21(4), 1047-1058. https://doi.org/10.1007/s12205-016-1615-x.
• Chan, A.P.C., (2001) Time-Cost Relationship of Public Sector Projects In Malaysia, International Journal of Project Management, 19, 223-229.
• Creemers, S. (2019) The preemptive stochastic resource-constrained project scheduling problem. European Journal of Operational Research, 277, 238-247.
• Elazouni, A.M., and Metwally, F.G., (2007) Expanding finance-based scheduling to derive overall optimized project schedules. Journal of Constitution Engineering and Management, 133(1), 86-90.
• Eshtehardian, E., Abbasnia, R. ve Afshar, A., (2008) Optimization of Uncertain Construction Time-Cost Trade-Off Problem, Advancing and Integrating Construction Education, Research & Practice, 1, 192-200.
• Geem, Z. W. (2010) Multi-objective Optimization of Time-Cost Trade-Off Using Harmony Search. Journal of Construction Engineering and Management, 136(6), 711-716.
• Gürbüz, F., Dinç, M., & Erdinç, G. (2020) Case Study for Getting Probability Distributions of Some Basic Construction Activities. Avrupa Bilim ve Teknoloji Dergisi, (Özel Sayı), 137-143.
• Haghighi, M. H., Mousavi, S. M., Antuchevičienė, J., & Mohagheghi, V. (2019) A new analytical methodology to handle time-cost trade-off problem with considering quality loss cost under interval-valued fuzzy uncertainty. Technological and Economic Development of Economy, 25(2), 277-299. https://doi.org/10.3846/tede.2019.8422
• Haque, K. M., & Hasin, M. A., (2012) Genetic Algorithm for Project Time-Cost Optimization in Fuzzy Environment. Journal of Industrial Engineering and Management, 5(2), 364-381.
• Hegazy, T., (1999) Optimization of construction time-cost trade-off analysis using genetic algorithms. Canadian Journal of Civil Engineering, 26(6), 685-697.
• K. El-Rayes, and A. Kandil, (2005) Time-cost-quality trade-off analysis for highway construction, Journal of Construction Engineering and Management 131 (4), pp.477-486. DOI: 10.1061/(ASCE)0733-9364(2005)131:4(477)
• Karaman, E. ve Kale, S., (2007) Bulanık Hedef Programlama Yöntemi ile Süre Maliyet-Kalite Eniyilemesi, 4. İnşaat Yönetimi Kongresi, 109-118.
• Kelley Jr, J. E. (1961). Critical-path planning and scheduling: Mathematical basis. Operations Research, 9(3), 296-320. Liu, L., Burns, S. A., & Feng, C. W. (1995) Construction time-cost trade-off analysis using LP/IP hybrid method. Journal Of Construction Engineering And Management, 121(4), 446-454.
• Martin, J., Burrows, T.K. ve Pegg, I. (2006) Predicting Construction Duration of Building Projects, Construction Economics, 28, 1-13.
• Parveen, S., & Saha, S. K., (2012) GA Based Multi-Objective Time-Cost Optimization in a Project with Resources Consideration. International Journal of Modern Engineering Research (IJMER), 2(6), 4352-4359.
• PMI., (2008). A Guide to The Project Management Body of Knowledge (4 b., Cilt 5). Pennsylvania: Project Management Institue.
• Pour, N. S., Modarres, M., & Moghadam, R. T. (2012) Time-cost-quality trade-off in Project scheduling with linguistic variables. World Applied Sciences Journal, 18(3), 404-413.
• Razek, R.H.A.E., Diab, A.M., Hafez, S.M., and Aziz, R.F., (2010) Time cost quality trade-off software by using simplified GA for typical repetitive construction projects. World Academy of Science, Engineering. & Technology, 61, 312-320.
• Shahsavari-Pour, N., Modarres, M., Tavakoli-Moghadam, R., & Najafi, E. (2010) Optimizing a multi-objective time-cost-quality trade-off problem by a new hybrid genetic algorithm. World Applied Science Journal, 10(3), 355-363.
• Sorrentino, M., (2013) Genetic Algorithms for Construction Time-Cost-Quality Trade-Off: ARoad Project Case Study. Construction Management, 2, 163-176.
• Suhail, S. A. and Neale, R. H. (1994) “CPM/LOB: New methodology to integrate CPM and line of balance.” J. of Construction Engineering and Management, ASCE, Vol. 120, No. 3, pp. 667–684.
• Thomas, N., G., Michael, M.Y., Skitmore, M., Lam, K.A.C., Varnam, Mark, (2000) The predictive ability of Bromilow’s time – cost model, Construction Management and Economics, 19, 165-173