This study examines the habits and attitudes of construction sector employees in Türkiye regarding the use of personal protective equipment (PPE). A comprehensive face-to-face survey was conducted with 398 randomly selected employees from small- and medium-sized construction companies across various regions of Türkiye. The survey aimed to identify the frequency of PPE usage and the factors influencing its use and to provide actionable suggestions for improving PPE compliance. The results indicate that while a majority of workers recognize the importance of PPE, actual usage rates are inconsistent. Key factors affecting PPE use include the ergonomics and comfort of the equipment as well as worker perceptions and attitudes. Notably, the study found that the discomfort associated with PPE and the belief that it slows down work pace are significant barriers to its regular use. Additionally, the research highlights the need for a robust punishment–reward system to enforce PPE compliance and suggests that more stringent legislative measures are required to enhance occupational health and safety (OHS) standards in the construction industry. This study contributes to the existing body of knowledge by providing a detailed analysis of PPE usage in the Turkish construction sector and offering practical recommendations for policymakers and industry stakeholders. Implementing these suggestions can lead to improved worker safety and reduced occupational accidents.

Sumela Monastery located in the northeast city of Trabzon is one of the most-visited touristic places in Turkey. As it is located in a mountainous area, rockfall hazards have become a crucial problem that the Monastery complex faces, especially in the last decade. Due to several rockfall cases, the monastery was closed for visitors in 2015 to take preventative measures. The current study examines the whole stages assessing and eliminating rockfall hazards that a historical Vaulted masonry building in the Sumela Monastery is exposed to. First of all, field studies were conducted to determine the kind and type of rockfall hazard. For this purpose, the regional geology of the area was evaluated and due to the inaccessibility of the region, industrial climbers were recruited to climb the slope above the Historical Vaulted building to determine the locations, dimensions, and risk level of the risky blocks that threatened the building. After that, the terrain of the risky area was modeled with Unmanned Aerial Vehicle (UAV) using the digital photogrammetry method. In the last step of the field studies, samples were taken to determine the mechanical and physical properties of the rocks and several laboratory tests were conducted. In the second part of the study, probabilistic analyses of 2400 rockfall simulations with eight different trajectories were conducted to calculate the maximum run-out distance, velocity, kinetic energy, and bounce heights of falling blocks. In the third part, to evaluate the damage status on the vaulted building, six different possible rockfall scenarios determined by the rockfall analysis were simulated using the Finite Element Method. After determining the rock block size that would not cause significant damage to the building, the cleaning and controlled removal method of the risky blocks was determined. In the last stage, controlled crushing and removing practices for risky rock blocks were carried out and the building was restored. Consequently, the rockfall hazard for the historical Vaulted building was eliminated and the monastery complex opened for visitors in 2021.

The selection of an appropriate construction method stands as a pivotal decision in ensuring the success of any building project. This paper undertakes a comprehensive comparative analysis of cost and timeline implications between the top-down and bottom-up construction methodologies. The research focuses on ten distinct underground structure models, each characterized by varying depths and base areas. Through rigorous design and analysis, the cost and projected duration for each model are meticulously evaluated under the lens of both top-down and bottom-up construction techniques. The findings reveal that while the bottom-up approach emerges as the most cost-effective alternative at a depth of 8 m, the top-down method exhibits superior cost efficiency with increasing depth. Interestingly, alterations in the structure’s base area exert a minimal influence on the cost differentials between the two methodologies. Moreover, the top-down construction method consistently outshines its counterpart in terms of project duration across all ten models examined, with the percentage increase in base area yielding insignificant impacts on project timeline discrepancies. This study furnishes construction project managers with invaluable insights to navigate the complexities of method selection. By judiciously considering parameters such as project scale, depth, and base area, managers can strategically optimize both cost and timeline outcomes, thereby facilitating the seamless execution of construction projects.