Identification and Prioritization of Indicators for Permanent Housing Construction Technology after an Earthquake in Tehran

Planning for housing construction after a probable earthquake in big cities has received less attention due to its complexity and ambiguity in urban settlements like Tehran. Since reconstruction is an opportunity for development and better construction, using up-to-date and suitable technologies in the building is inevitable. The new technology used in the construction of housing after earthquakes must have these features: high construction speed, lower cost, low energy consumption, compatibility with the environment, appropriate stability and strength, seismic resistance, and consequently higher useful life of buildings. Due to the wide dimensions of construction technologies, high implementation costs and the need to have executive knowledge and cognition of post-disaster conditions, the use of suitable and appropriate technology in all dimensions and components of the building requires a correct understanding of the indicators. The current research aims to identify and prioritize the indicators of permanent housing construction technology after the earthquake in Tehran using the Delphi method and Shannon's entropy technique.The research methodology applies a combination of qualitative and quantitative methods based on analytical and exploratory strategies. After reviewing the articles, documents and specialized texts as well as examining the experiences from previous studies, indicators were extracted and classified using the Delphi method then approved by the experts and ranked using Shannon's entropy technique. After that, the opinions of ten experts, senior managers, officials, and eight university professors aware of the field of housing in Tehran were used. By referring to the qualified specialists and experts in the field of housing construction technologies after the earthquake and by visiting the relevant departments and organizations, senior managers, and officials in person, questionnaires were completed by experts in the field of housing and university professors knowledgeable in the field of housing who made up the target statistical population. Then, to achieve the indicators, the research background, publications and published documents related to the subject were reviewed.For this purpose, the indicators obtained through interviews with experts were examined, and among dozens of cases, after combining similar cases and including overlaps, removing unrelated and ambiguous cases, and making necessary corrections, 78 variables were selected as the indicators in the field of housing construction technologies were identified after the earthquake in Tehran.In the first step, a questionnaire was designed under the title of weighting indicators of housing construction technology after a possible earthquake in Tehran, which included 12 components and 90 sub-components and was given to 18 experts to rate each index based on a 5-point Likert scale. It is worth mentioning that the experts were asked to mention, in addition to the determined indicators, if they consider another influencing factor. In the research process, the majority of experts agreed, some added new components, and some did not express an opinion. Then, in the second round, items with an average of less than 3.5 were removed and new items were added. Thus, during two stages and using the Delphi method, various items of post-accident housing construction technologies were extracted. The meaning of housing in this research is permanent and conventional housing of 5 to 7 floors with an area of 70 to 90 square meters in Tehran, which is usually assumed to start construction after the stages of emergency and temporary housing. Twelve effective components in housing construction technology after the Tehran earthquake have been identified in previous studies. These factors include construction and execution management, cost, housing construction components, type of materials, time, prefabrication, energy consumption, safety, cultural and social characteristics, environmental conditions and compatibility with the architectural design, which are categorized into four managerial, economic, social and cultural sectors.The results show that among the refined indicators, "quality, durability and high resistance of housing construction materials", "application of existing standards of the construction industry in building systems", "main structure of housing", "supplying space light", "minimum required energy for climate adaptation" and "considering different areas of Tehran" were recognized as the most important indicators of housing construction technology after earthquakes.The criteria with high priority in housing construction technology can be analyzed from the structural and non-structural points of view.A Scrutinizing look shows that there are factors in the construction technologies considered by the respondents, which are mostly non-structural and architectural and the view of builders and designers from the scope of structural and physical issues of housing to other categories in the construction process, including Management, architectural and social factors have been focused in Tehran.