Assessment of the Disaster Recovery Progress through Mathematical Modelling

Natural disasters, especially major earthquakes, cause widespread devastation in the built environment. Hence, the major component of the recovery in its aftermath constitutes a chain of projects starting at different times, having different costs and durations. In this study, the post disaster recovery curve modelled through a mathematical approach taking into account these properties of the projects. The approach followed is based on the project S-curve concept that provides the opportunity to simulate the progress by outlining the project spending. Well-known mathematical functions are adapted to model the project spending and the handover processes. Monte Carlo simulation is performed to evaluate the general behavior of the recovery curve using the model developed. Weibull distribution is used to generate the model’s parameters. Results of Monte Carlo simulation demonstrate that the recovery process exhibits an S-shape; the duration of initial portion and the slope of the bulk portion being significantly governed by the level of preparedness of the community.WOS:0005583601000042-s2.0-8510871143

Time - Cost Relationships for Superstructure Projects in Turkey

The concept of time-cost relationship in construction projects was first introduced by Bromilow, using the data of the 328 superstructure projects completed in Australia. The aim of this study is to determine the time-cost relationship of superstructure projects in Turkey. Time and cost data of 460 superstructure projects completed between the years of 1999-2018 was used in the study. Data was grouped primarily on the basis of the intended use of buildings (individual buildings, educational buildings, hospitals, industrial buildings and social housing), and then time-cost relationships were separately determined for each group through statistical analysis. In addition, the effects of the parameters such as exchange rates and the number of non-working days on the time-cost relationship were investigated statistically, as well. As a result of this study, highly meaningful time-cost relationships (R2 =0,60) are determined for the construction projects in Turkey, excluding disaster relief projects, which is not part of this study. It has also been determined that while the hospital projects in Turkey have the highest coefficient of determination (R2= 0,87), social housing projects have the lowest (R2= 0,54).WOS:0005184740000042-s2.0-8508643707

Modal identification of the first Bosporus bridge during hanger replacement

As the oldest of the three suspension bridges spanning the Bosporus, the (First) Bosporus Bridge wascommissioned in 1973. Its main span of 1074 m was originally designed to be suspended by inclinedhangers; in 2015, the original inclined hangers were replaced by vertical ones. In-situ ambient vibra-tion measurements were taken at different stages of this operation to gain an understanding of theeffects of the hanger cable orientation on the overall dynamic behaviour of the bridge. Measurementswere also recorded for various periods spanning several weeks to observe operational variations onthe modal frequencies of vibration. Measurements were made on the tower, the deck and the hang-ers. It was observed that, as a result of the hanger replacement, frequencies of the modes involvingpredominant deck motion decreased on the order of 6 to 16% while the frequencies of the modesinvolving predominant tower motion showed almost no change. A finite element model of the Bridgewas also developed to further investigate the physical reasons behind the observed changes in modalfrequencies and similar trends were observed in the modal frequencies yielded by the finite elementmodels developed for the inclined and the vertical hanger configurations.WOS:000511783100001Scopus - Affiliation ID: 60105072Science Citation Index ExpandedQ2ArticleUluslararası işbirliği ile yapılmayan - HAYIRAralık2020YÖK - 2020-2

A field study about the development of occupational safety expertise system

İş kazalarının en aza indirilmesi amacıyla 2012 yılında 6331 sayılı “İş Sağlığı ve Güvenliği Kanunu” yürürlüğe konmuştur. Kanun, işyeri tehlike sınıfı ve çalışan sayısına bağlı olarak, işyerlerince iş güvenliği uzmanından hizmet alınmasını zorunlu kılmaktadır. Bu kanun kapsamında yayınlanan 28512 sayılı yönetmelik ile de iş güvenliği uzmanlarının görev ve yetkileri düzenlenmiştir. Ancak, her yeni uygulamanın sorun ve eksikliklerinin giderilerek tam anlamıyla kabul görmesi ve işlerlik kazanması belirli bir süre gerektirmektedir. Bu çalışmanın amacı, 2015 ve 2017 yıllarında yapılan anket çalışmaları ile iş güvenliği uzmanlığı konusundaki sürecin bir değerlendirmesinin yapılmasıdır. Ankete, 2015 yılında 63, 2017 yılında ise 75 uzman katılmıştır. Anketler, kıyaslamalı olarak değerlendirilerek, aradaki zaman dilimi içerisindeki gelişmeler değerlendirilmiştir.In 2012 the “Occupational Health and Safety Code”, code numbered 6331 is enacted with an objective to reduce the occupational accidents to a minimum. the code required the businesses to procure the services of an occupational safety expert based on the danger class of the workplace and the number of employees. in this respect, the scope and the authority of the work safety experts is organized in regulation number 28512. Yet, every new procedure requires time for sifting out the problems for being accepted and become operational fully. the objective of this study is to make an evaluation of the process regarding the occupational safety experts through questionnaire studies performed in 2015 and 2017. in 2015 and 2017, 63 and 75 experts attended survey, respectively. the surveys are evaluated comparatively to observe the developments within the selected period