نشریه عمران و پروژه
سال پنجم شماره 1 (پیاپی 47، فروردین 1402)

Nowadays, the close competition of airline companies in attracting passengers has made it very important for planners and policymakers in this field to investigate the psychological issues and the differences in the passengers' views. Different airline companies seek to examine the ideals and values of passengers in order to identify their strengths and weaknesses in order to maintain their position in the competitive market or promote it with correct and accurate planning. In this study, various factors affecting satisfaction from the passengers' point of view are examined using survey data and logistic regression modeling. The factors examined in this study include characteristics such as age and gender, loyalty to the airline, and the level of satisfaction with the quality of various services such as food and internet services, baggage handling services, and online ticket booking. In addition, the effect of variables related to each flight, such as distance and delays, are also investigated on passenger satisfaction. The modeling results of this research show the importance and significance of the variables of type of travel (personal or business), type of passenger (loyal or not loyal to the company), class of travel (Eco or Eco Plus or business), the level of satisfaction with baggage handling and the level of satisfaction with the boarding process. This study has shown the high sensitivity of passengers to the process of getting on the plane and also to baggage handling.

The expansion of the planet's population and the need for the construction industry has caused a shortage of primary materials. On the other hand, the process of making and using these materials causes harmful damage to the environment and causes the pollution of natural resources and the release of carbon dioxide (CO2) in nature. In addition to this, plastic polymers used in various industries are one of the most consumed items that cause environmental pollution and the waste recycling process is costly and time-consuming. One of the most widely used polymers is polyvinyl chloride (PVC), which is used in the industry of making wires, electric cables, and all kinds of mobile phone chargers as a cover for their conductors.Limited studies have been done in the field of reusing this polymer as a member of the concrete structure as fibres and improving its mechanical properties in the past. This study deals with a comprehensive review of these studies in the field of using these types of fibres that have been used as reinforcing and reinforcing properties of concrete and focuses on a detailed investigation of the effect of different percentages and various dimensions of these types of fibres on the mechanical characteristics of concrete.

One of the challenges of using reinforced concrete structures is the corrosion of reinforcements in aggressive and corrosive environments such as offshore structures, stairs, etc., which will eventually lead to the destruction of concrete structures. To solve the corrosion problem in this category of structures, experts turned to the use of rebars with epoxy coating as a suitable alternative to conventional rebars. Most FRP rebars on the market today are made of high-performance continuous fibers such as glass, carbon and aramid, which are embedded in a polymer substrate by various composite production methods. FRP amplifiers are commonly used in various forms in the form of networks, rebars, textiles or cables. In this research, the numerical behavior of FRP hybrid reinforced concrete compression members and its modeling under concentric loading is investigated. All modeling is performed in ABAQUS finite element software and is evaluated using nonlinear analysis.