نشریه عمران و پروژه
سال سوم شماره 9 (پیاپی 31، آذر 1400)

Shorter columns absorb more seismic force than conventional columns due to their higher stiffness. For this reason, short columns are seriously damaged during an earthquake and sometimes cause damage to the entire structure. It has been shown that when short columns are displaced as much as long columns, they absorb more energy. As a result, this phenomenon causes shear and joint failure in the short column. In this research, using the experimental results of a short column that has been affected by lateral reciprocating loads, an attempt was made to select the most optimal form with the help of steel sheets covered in different shape patterns to be developed by scientific study. Provide design relationships for this retrofit method. For this purpose, to determine the effect of reinforcement on the short column, six different modes of installation of the proposed steel cover in Abacus software were used for finite element analysis. Also, the studied short column was subjected to reciprocating cyclic loading according to the ATC24 standard pattern. The results of this study showed that the reinforcement of the short column with integrated steel sheet is able to increase the seismic resistance of the column by 49%, but the most optimal method of reinforcement in terms of strength and volume of steel used is the reinforcement method with mesh pattern installation.

One of the important differences between the properties of ordinary concrete and heavy concrete is the use of metal or mineral aggregates instead of sand in concrete. Using ilmenite powder as a substitute for currently used heavy metals such as lead in concrete can reduce costs as well as sustainability and environmental protection. Use of heavy concrete to prevent harmful radiation for construction of hospital, military, nuclear centers and also to increase durability and resistance to wear and penetration of chloride ions for the construction of offshore concrete structures such as ports, offshore oil rigs, breakwater walls and Lighthouse or used in dam industry. In this research, an attempt was made to evaluate the durability of heavy concrete against intrusion by using a laboratory program using heavy grain of ilmenite and in order to support the production of domestic industries and mines using ilmenite powder of titanium mine in Kahnooj city of Kerman province. Chloride attack ions should be treated by RCMT method. In this research, samples made according to ACI standard by absolute volumetric method and laboratory optimization based on the type and properties of materials used have been prepared. The heavy concrete mixing plan has been adapted by replacing ilmenite powder with a maximum size of 1 mm in volume ratios of 10%, 20%, 30%, 40%, replacing sand in concrete and cement grade of 450 kg per cubic meter. The results of this study show that the use of ilmenite powder in heavy concrete increases the density of concrete and reduces the penetration rate of attack ions in concrete, so that by adding 20% and 30% ilmenite powder in the concrete structure, respectively, chloride ion penetration coefficient of 27% And is reduced by 22%.

In this study, in order to identify the effect of coaching skills of the manager of landscaping projects and cultural buildings of Mashhad airport in obtaining feedback from the interactive relationship with the project stakeholders, coaching skills indicators and components of each have been identified. Given that coaching is a set of skills of active listening, empathy and questioning in the context of building trust, by searching the text of books, standards, articles, interviews, etc., components for these skills are extracted and a group of experts and specialists in the field. Coaching and project management in the Delphi process reached a consensus on these components and to measure the impact of each of these components on stakeholder interaction and their effective feedback to the project manager, questionnaires based on a 5-point Likert scale were used. These questionnaires among the statistical population of the present study include internal and external stakeholders of the project under study, such as: direct employees in the project, employees in other parts of the project, airport project investors, residents and employees near the airport, people whose business is affected. It is the airport and people who come to the airport for travel or other purposes were distributed and collected. Analysis of the descriptive statistical data of this study by SPSS software indicates that: Participants will interact with the project manager to a large extent to the project manager if any of the components of coaching skills occur. By inferential analysis of statistics, active listening skills, confidence building, questioning and empathy were ranked respectively and it was concluded that active listening skills, empathy, questioning and confidence building have a significant correlation with each other and this correlation can be generalized to the statistical community.

With the increasing population of urbanization and the use of private transportation, the depreciation of public transportation in Iran's metropolises and issues such as environmental, traffic, visual and air pollution, urban management policies in this direction Appropriate solutions such as sustainable urban development should be adopted. This article intends to show by introducing practical strategies at the level of metropolitan management To achieve sustainable urban development, the component of sustainable transport development must first be taken seriously. Sustainable transport is a set of integrated, dynamic, continuous policies and guidelines that include economic, social, and environmental goals that ensure the equitable distribution and efficient use of resources to meet the transportation needs of society and future generations. Brings with it. The method of collecting information and data is library and case study. The purpose of this article is to address the important components of transportation network planning and the dimensions of sustainability in urban transportation networks, the process of determining the policies of senior managers in order to achieve the development of urban sustainability through sustainable development. Transportation is achieved through strategic management and the use of the swot model.

Application of dual SMRF-BRBF system can be considered as an appropriate choice for resisting seismic loads in high seismicity regions. Taking advantage of having buckling resistant braces which can resist high axial compressive forces without local and global buckling, buckling restrained bracing frame (BRBF) system can be used as an efficient alternative for conventional bracing system. Response modification factor (R factor) is required for seismic design of structures. Therefore, in this research, performance-based R factor is evaluated for dual SMRF-BRBF structures. Considering the fact that in addition to structural properties the seismic load characteristics effect on the load-carrying capacity and R factor, R factor is evaluated specifically for near fault ground motions. To consider the effect of performance level, the R factor is calculated distinctly for Life Safety (LS) and Collapse Prevention (CP) limit states. Nonlinear time history and pushover analysis results are employed for determination of ductility, over-strength and R factor of the sample structures. According to the obtained results, the average of R factor coincident to LS and CP performance levels is 6.1 and 7.9, respectively. The comparison of results obtained for near fault records with those obtained for far fault motions reveals that the R factor is averagely 25% lower for near fault ground motions.

In spite of the development of theories related to the early stages of the project life cycle (feasibility studies and initial planning), it is still unclear to what extent the project stakeholders have sufficient belief regarding the necessity and implementation of these initiation phases in practice. This research has been conducted with the aim of measuring the efficiency of implementation of feasibility study in construction projects (especially in Iran) and proposing a solution to improve its efficiency in the future. The data collection tool is questionnaire based and has been measured and analyzed using the relative importance index (RII) of the following items: Measuring the efficiency of existing feasibility methods, Developing and controlling its performance and Knowledge-based feasibility study. The results of this analysis revealed the factors such as (Sequence of tasks, bottom-up management and appropriate work breakdown structure) that are of particular importance for the development of the initial phase of projects. Also, the general findings indicate that this research can be used to clarify how to strengthen the link between related theories and the use of these theories in the implementation of projects in practice. In addition, this research can provide new insights for project managers and stakeholders towards the new knowledge-based management strategies and tools and also can implement the project team training system to improve the level of insight and understanding of project stakeholders from the early stages of the life cycle in the current practices of construction projects.