İnşaat Projelerinde Zaman Maliyet Ödünleşim Problemi: Örnek Olay Analizi

Globalleşen dünyada artan rekabet koşullarıyla birlikte inşaat projelerinin gerek zaman gerekse maliyet olarak optimize edilmesikaçınılmaz bir hal almıştır. Bu ortamda proje yöneticisinin karşı karşıya olduğu en önemli zorluklardan biri, projeye ayrılan zaman vefinansal kaynak kısıtları içerisinde istenilen kalite standartlarına göre projenin yapılabilirliğine karar vermek ve sonrasındatamamlanmasını sağlamaktır. Günümüzde proje yöneticileri sürekli bir zaman ve maliyet indirgenmesi baskısıyla karşı karşıyadır. Bunoktada her bir proje için zaman ve maliyet ödünleşiminin nasıl yapılacağı ve hangi türden bir model geliştirileceği proje yöneticilerininüzerinde çalıştığı en ciddi problemlerden birisi olarak karşımıza çıkar. Bu çalışmada, proje kısıtlamaları altında zaman ve maliyeti enaza indirmeyi amaçlayan CPM tabanlı bir proje hızlandırma modeli sunulmaktadır. Geliştirilen model örnek bir inşaat projesine aitderlenmiş verilerle uygulanmıştır. Araştırmada ilk olarak hızlandırma sürelerini ve maliyetlerini bulmak için kritik yol yöntemi (CPM)kullanılarak kritik yol ve bu yol üzerindeki kritik aktiviteler belirlenmiştir. Projede yer alan faaliyetlerin sürelerinin deterministik olduğuöngörülmüştür. Probleme ilişkin amaç fonksiyonunun belirlenmesi için kritik yol üzerindeki her bir faaliyetin hızlandırma maliyetlerive maliyet eğimleri hesaplanmıştır. Oluşturulan modeldeki zaman ve maliyet parametreleri arasındaki ilişkiyi tanımlayabilmek içinproblem MATLAB programı ile çözülmüştür. Analiz sonucunda projenin 19 haftadan 13 haftaya kadar kısaltılabileceği hesaplanırken,en uygun 741 bin TL. bütçe ve 2 hafta hızlandırmayla toplam 17 haftada tamamlanabileceği görülmüştür.

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

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.

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