Mohammad Lemar ZALMAI - Academia.edu (original) (raw)

Papers by Mohammad Lemar ZALMAI

6 th international Project and Construction Management Conference (IPCMC2020) Istanbul Technical University, 2020

Most of the construction projects are exposed to time and cost overruns due to various factors an... more Most of the construction projects are exposed to time and cost overruns due to various factors and this is a major problem. As a solution to this, the Earned Value Management (EVM) method is considered. EVM is a powerful and well-known method used in monitoring and controlling the project. EVM gives an early indication that either project is delayed or not and the project is either over budget or under budget at any particular day by tracking it. Thus, it helps to improve the management control system of a construction project, to detect and control the problems in potential risk areas and to suggest the importance and purpose of monitoring the construction work. This paper explains the main parameters of the EVM system involved in the calculation of time and cost for construction projects. In this study, the Primavera P6 software is used to deals with the project monitoring process of a seven-storeyed (G+6) faculty building whose construction is in progress at Istanbul, Turkey. A comparison between the planned progress of construction activities and actual progress is performed and the analysis results are interpreted. This case study justifies the benefits of using EVM for project cash flow analysis and forecasting.

World Academy of Science, Engineering and Technology, International Journal of Civil and Environmental Engineering, Jun 24, 2021

In recent years, the Building Information Modeling (BIM) approach has been developed expeditiousl... more In recent years, the Building Information Modeling (BIM) approach has been developed expeditiously. As people see the benefits of this approach, it has begun to be used widely in construction projects and some countries made it mandatory to get more benefits from it. To promote the implementation of BIM in construction projects, it will be helpful to get some relevant information from surveys and interviews. The purpose of this study is to research the current adoption and implementation of BIM in public projects in Turkey. This study specified the challenges of BIM implementation in Turkey and proposed some solutions to overcome them. In this context, the challenges for BIM implementation and the factors that affect the BIM usage are determined based on previous academic researches and expert opinions by conducting interviews and questionnaire surveys. Several methods are used to process information in order to obtain weights of different factors to make BIM widespread in Turkey. T...

Revista de la construcción

International Journal of Civil and Environmental Engineering, 2020

6 th international Project and Construction Management Conference (IPCMC2020) Istanbul Technical University, 2020

Revista de la Construcción. Journal of Construction, 2019

In construction projects, the relationship between project cost and duration, which is one of the... more In construction projects, the relationship between project cost and duration, which is one of the main factors of the project, are considered the parameters decision-makers. When a construction schedule is planned by the planners, additional resources are allocated to shorten the project duration considering the completion time and cost of the activities so that the most suitable construction schedule is prepared by providing a trade-off between project duration and total cost. In the case of time-cost trade-off problems, the total cost of the project is determined by summing each activities' cost by adding indirect costs. Moreover, total project duration is determined by obtaining total project duration after CPM (Critical Path Method) calculations. Obtaining optimum duration and costs is such a problematic issue with using conventional methods and common software packages. These techniques consider deterministic project values and include CPM calculations for fitness value calculation. Moreover, current studies defined alternatives as non-variable discrete values. However, construction projects are dynamic processes, and quantities are prone to be changed related to project size. In this study, time-cost trade-off optimization is performed by using harmony search method with introducing different implementation that can be more easily used for different projects. The model is implemented in a real construction project, and the conclusions are interpreted.

Resumen: En los proyectos de construcción, la relación entre el costo y la duración del proyecto, que es uno de los principales factores del proyecto, se consideran los parámetros que toman las decisiones. Cuando los planificadores planifican un cronograma de construcción, se asignan recursos adicionales para acortar la duración del proyecto considerando el tiempo de finalización y el costo de las actividades, de modo que el cronograma de construcción más adecuado se prepare al proporcionar un intercambio entre la duración del proyecto y el costo total. En el caso de problemas de compensación de tiempo y costo, el costo total del proyecto se determina sumando el costo de cada actividad al agregar los costos indirectos. Además, la duración total del proyecto se determina al obtener la duración total del proyecto después de los cálculos de CPM (Método de ruta crítica). Obtener una duración y costos óptimos es un problema tan problemático con el uso de métodos convencionales y paquetes de software comunes. Estas técnicas consideran los valores deterministas del proyecto e incluyen cálculos de CPM para el cálculo del valor de aptitud. Además, los estudios actuales definieron alternativas como valores discretos no variables. Sin embargo, los proyectos de construcción son procesos dinámicos, y las cantidades son propensas a cambiar en relación con el tamaño del proyecto. En este estudio, la optimización de la compensación de tiempo y costo se realiza utilizando el método de búsqueda de armonía con la introducción de diferentes implementaciones que se pueden usar más fácilmente para diferentes proyectos. El modelo se implementa en un proyecto de construcción real, y se interpretan las conclusiones. Palabras clave: Sector de la construcción, CPM (Método de ruta crítica), optimización multiobjetivo, método de búsqueda de armonía, compromiso tiempo-costo.

4. Proje ve Yapım Yönetimi Kongresi, 3 – 5 Kasım 2016, 2019

Özet İnşaat Sektöründe CPM in iki değişik uygulama alanı vardır. Birincisi, proje öncesi faaliyet... more Özet İnşaat Sektöründe CPM in iki değişik uygulama alanı vardır. Birincisi, proje öncesi faaliyetlerin süresel olarak planlama ve proje gidişatı hakkında tahmin yürütme, bunun yanında projenin geçmişine dönük bir kara kutu görevi görmektedir. Dünyadaki inşaat sektöründe sıklıkla kullanılmakta iken Türkiye'de halen yeteri kadar yaygın bir şekilde uygulanmamaktadır. Ve bu durum gerek proje esnasında veya proje bitiminde yaşanan uyuşmazlıklarda bu eksiklik kendini belli etmektedir. Bu çalışmada bir kamu binası inşaatı sürecinde CPM uygulaması ve uygulama esnasında CPM in proje gidişatına ne kattığı ve yeterli derecede kullanılmaması durumunda ne gibi problemlere yol açtığı incelenmiştir. Giriş Türkiye inşaat sektörü uluslararası bir seviyeyi yakalama potansiyeline sahip olmasına rağmen, inşaat yönetimi anlayışı firmalarımız tarafından henüz tam olarak benimsenmiş değildir. Gerek yönetmeliklerde zorunlu olmaması, gerekse işveren ve müteahhide sağlayacağı avantajların bilinmemesi nedeniyle ülkemizdeki uygulamalar yeterli düzeyde değildir. İş programı (CPM) olmayan bir projede, faaliyet tabanlı maliyetlendirme, proje ve ekipman performansı, zaman ve maliyet tahmini vb. konular sağlıklı olarak yapılamamakta, genellikle deneyimle veya güvenilir olmayan hesaplamalarla (el yordamı) ile problemlere çözümler aranmaya çalışılmaktadır. Bunların yanı sıra risk ve sorumlulukların dağıtılması, proje süresinin kısaltılması ile katlanılacak maliyetler vb. konular bilimsel olarak yapılamamaktadır. Çalışmada CPM'in iki anlamıyla birlikte kullanılmamasının taraflara ne gibi problemlere yol açtığı örnek vakalarla ortaya konmakta, ülkemizde sıkça yaşanan böyle durumlarda neler yapılabileceği konusu tartışılmaktadır.

5th International Project and Construction Management Conference (IPCMC2018), 2018

In construction projects, construction errors affect negatively to the production, that influence... more In construction projects, construction errors affect negatively to the production, that influences the overall of the project in both time and budget. Generally, construction companies could not estimate this kind of errors during the bidding process. In this case, these companies did not consider important issues on the budget of the contract, and in the contracting period, project participants assumed that the project would be executed as it scheduled and designed. During the project, different construction processes' costs are higher than estimated values due to construction errors. The errors that were recognized during the construction process cause time and financial losses, on the other hand, the errors that were noticed after the project's termination cause repair and correction costs. Moreover, the company may gain a bad reputation in the sector. The key points of this study are to analyze project costs by considering construction errors and reconstruction costs due to labor errors by using fuzzy interpretation mechanism. This methodology is applied to a residential construction project. With using of this methodology, forthcoming extra costs related to construction errors can be estimated. And some precautions can be taken for further legal conflicts between parties.

ACE 2014, 11th International Congress on Advances in Civil Engineering, 2014

Project cost and project duration are main factors in construction management. In real-life proje... more Project cost and project duration are main factors in construction management. In real-life projects, both the trade-off between the project cost and the Project completion time, and the uncertainty of the environment are considerable aspects for decision-makers. Moreover, in some projects, activity durations show their complexity with time-dependence as well as randomness. Time cost trade off problem have been solved by using vast of methods such as genetic algorithms, particle swarm optimization. Most of these studies considered deterministic project values and includes CPM calculations for fitness value calculation. However most of construction projects are stochastic processes. In this paper, a stochastic time-cost trade-off problem is introduced. This study takes into account that activity duration and cost are uncertain variables. this study differs from other studies that for each fitness value calculation. The proposed model is dealt with an intelligent algorithm combining stochastic simulation and Harmony search, where stochastic simulation technique is employed to estimate random functions and Harmony search is designed to search optimal schedules under different decision-making criteria. Beside this Monte Carlo simulation is made for fitness value calculation in order to make more realistic optimization. Finally, some numerical experiments are given to illustrate the algorithm effectiveness.

International Journal of Civil and Environmental Engineering, 2020

6 th international Project and Construction Management Conference (IPCMC2020) Istanbul Technical University, 2020

World Academy of Science, Engineering and Technology, International Journal of Civil and Environmental Engineering, Jun 24, 2021

Revista de la construcción

International Journal of Civil and Environmental Engineering, 2020

6 th international Project and Construction Management Conference (IPCMC2020) Istanbul Technical University, 2020

Revista de la Construcción. Journal of Construction, 2019

4. Proje ve Yapım Yönetimi Kongresi, 3 – 5 Kasım 2016, 2019

5th International Project and Construction Management Conference (IPCMC2018), 2018

ACE 2014, 11th International Congress on Advances in Civil Engineering, 2014

International Journal of Civil and Environmental Engineering, 2020