Kaynakların kısıtlı olduğu koşullarda bir inşaat projesinin sezgisel yöntemle planlanması

Yaşadığımız son yüzyılda kaynakların uygun kullanımı ekonomik hayatın öncelikli hedefi haline gelmiştir. Bu bakımdan son yıllarda inşaat sektöründe kaynak kullanımı önem kazanmıştır. İnşaat üretiminde çok sayıda farklı imalat ve bu imalatlar içinde çok sayıda farklı kaynak gerekmektedir (iş gücü, makine gücü, malzeme, para vb.). İnşaat projelerinin boyutları oldukça büyük ve karmaşıktır. Bu projelerin gerçekleşmesi sürecinde, kaynakların öngörüldüğü zamanda ve öngörüldüğü miktarda bulunabileceği düşünülmemelidir. Bu bakımdan kaynak kullanımının da planlanması gerekmektedir. Bu çalışmada kaynakların kısıtlı olduğu koşullarda programlama yöntemleri genel olarak incelenmiş ve sezgisel yöntem ile çözüm yapabilen 2 (iki) algoritmanın uygulanması açıklanmıştır. Uygulanan algoritmalar öncelik kuralı prensibine göre çalışmaktadır. İlk algoritmanın birinci önceliği, projenin başlangıcından bitişine kadar, faaliyetlerin sürelerinin büyükten küçüğe doğru sıralanması; ikinci önceliği süresi eşit faaliyetlerinden bolluk süresi az olana öncelik vermesi ve üçüncü önceliği de süresi az olan faaliyete öncelik vermesidir. İkinci algoritmayla da; faaliyetlerden bolluğu az olana birinci öncelik, süresi fazla olana ikinci öncelik ve süresi az olana da üçüncü öncelik verilmektedir. Bu algoritmalar bir köprü inşaatı projesine uygulanmış ve performansları incelenmiştir.Buna göre kaynakların sınırsız olduğu koşullarda 46 gün içerisinde tamamlanan proje; günlük kaynak l adet kazı makinesi, 80 m2 kalıp, 10 ton demir, 16 m3 beton, 15 işçi olarak alındığında; her iki algoritmayla yapılan programlamaya göre de 58 günde tamamlanmaktadır.

Planning of a contruction project with intuitive approach under limited resources conditions

Adequate use of resources has become a target of high priority for the economics of the last century. Parallel to the general tendency, national use of resources in the construction industry has become more and more important the field of construction comprises of various sorts of production processes and each process require a number of different resources (labour, machinery and equipment, materials, finance, etc). Accordingly, a construction project, in many cases, may prove to be complicated and huge in terms of contents. When undertaking these projects, difficulties in providing the required amount of a specific resource at the required time are likely to arise. Consequently, a strict policy of planning for the use of resources is essential. In this work various methods of programming have been worked out with a special emphasis on the cases of limited resources and the application of the algorithms employed, work according to the principle of priorities rule. The prime priority of the fist algorithm is putting all the activities, from the start to the end, into an order of decreasing lengths of period duration. The one with- a shorter time of resource abundance takes the urgency. The activities with shortest duration are given the third place in terms of urgency. In the second algorithm, the resource with the least abundance, was given the first priority whereas the are with a longer duration was considered to be of a lesser priority and the activity of the shortest run was third. The both algorithms were applied on the construction works of a bridge and their performances were investigated. Under the conditions of unlimited resource, the construction was to be completed in 46 days whereas, one excavator, 80.0 of concrete template, 10 tons of iron, 10.0 m3 of concrete and 15 workers, on the daily basic, a delay of 12 days was inevitable with the both algorithms.

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