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Now a day, earthquake engineers follow subjects such as structural health monitoring, warning announcement and prediction rather safe-making in the field of structure. In this regard, these three choices are of great goals of Iran in direction of many studies concentrated on. This research is centralized on real time health monitoring system of Iran bridges. In this regard, to evaluate smart real time health monitoring sensors, first all different types were determined using the library resources, and then all the important indices in evaluating these sensors were derived by interviewing experts in construction management fields. After that, to continue the survey, questionnaires were given to 18 experts to weight the effective indices. Through a decision-making method using new hybrid methodology based on SWARA and WASPAS, existential necessity degree of all indices and sensors were obtained and eventually the following result captured: applying piezoelectric sensors is optimal in smart health monitoring to be used in Iran bridges and optical fiber sensor was recognized as the second optimum option.

Breathable air inside the tunnel is an undeniable necessity and beside natural ventilation, the tunnel should be reliably organized, to automatically provide healthy air under different conditions. Among methods of tunnel ventilation, longitudinal and transverse modes are the most common mechanical methods. This research is focused on selection of the optimal method for mechanical longitudinal ventilation of tunnel pollutants from four presented models. In terms of this research, the authors used SWARA (Step-wise Weight Assessment Ratio Analysis) as one of the most versatile MCDM (Multiple-Criteria Decision-Making) methods for managerial decision making in complex situations with multiple and varied measures. Fourteen experts of different fields were involved. The research model was established based on expert ideas and the following criteria: smoke control (C 1 ), safety level (C 2 ), design complexity (C 3 ), investment costs (C 4 ), increasing concentration of pollutants until portal (C 5 ), smoke laden section (C 6 ) and simultaneous evacuation and fire fighting (C 7 ). SWARA method was applied to evaluate criteria while VIKOR (VlseKriterijumska Optimizacija I Kompromisno Resenje) method was used to evaluate and rank four alternatives of this research, namely: 1) jet fans with spot extraction by axial fans (A 1 ); 2) axial fans with Saccardo nozzle (A 2 ); 3) jet fans with shaft axial fans (A 3 ); 4) jet fans only (A 4 ). Final results illustrate that jet fans with spot extraction by axial fans is the best choice. Finally, the authors believe that this new hybrid model of MCDM methods can be useful as a new framework in different fields of research.

Accidental and intentional explosions are incidents often destroying buildings and leaving casualties. As a result of these blasts all over the world, demand of safe constructions with less vulnerability to explosions is rising. A large number of office buildings are built each year in many countries, housing large numbers of staff and clients, and due to specific nature and function, activities and services, these buildings are usually centrally located. Their architectural form being vital, therefore the article attempts, firstly, to present indices depicting the building form from the viewpoint of vulnerability to explosion. Secondly, the article presents such indexes as: capability to reduce blast effects, economic factors, simplicity of implementation, relationship among spaces in the crisis condition, and creating the least unusable space. The model of rapid assessment of vulnerability of office buildings forms to blast, SMART (simple multi attribute ranking technique) procedure is used and, applying the SWARA method, the weight of each major index and sub-index is arrived at. The model presented in the paper shows the assessment systems using figures between zero and a hundred, and four levels of vulnerability: weak, medium, good and excellent. The closer the figure to a hundred, the lower the vulnerability of the office building forms to blast. Swiss Re Tower case study was presented in the article rating of vulnerability of this building against explosion. It was found to be equal to 62.11%, and its standing was at medium level.

Two earthquakes of magnitude 6.1mb occurred at the Ahar and around 16000 residential buildings were destroyed. one of the conspicuous issues in the earthquake is property management to reconstruct and confront the crisis. in this regard, since the most damage inflicted on the buildings occurs in the exterior walls, therefore, the most financial resources must be spent on reconstructing this part of damaged buildings. Thus, this paper was conducted in order to reduce expenditure and increase the resistance of the walls. The urban fabric of the area didn’t sustain much damage and only the exterior walls of the buildings were collapsed. Thus, the main aim of this article is to study different types of exterior walls for renewal and reconstruction of buildings in earthquake area. To approach this aim, using group decision-making method. This paper presents the comparison of FUZZY and AHP. in this regard, this research is centralized on types of exterior walls to reconstruct iran earthquake areas (Ahar, Heris, Varzeqan). five main methods have been chosen by asking experts in the related fields and to evaluate and select the best of exterior walls. finally 3D panel wall was selected as the optimal wall for reconstruction of earthquake area.

ABSTRACT.One of the most significant issues in the safe underground spaces is the supply of light during the conditions in which there is no possibility to use national electricity network in crisis. Hence, attention to the source management of light supply possesses worthy importance. Light is one of the important issues in underground safe spaces which must be noticed with particular obligations. In the research, in order to evaluate variety of light supply methods in underground safe spaces, a questionnaire was set in order to weigh affective indexes up and score each method. To determine the best index among different indexes, SWARA method was applied; then COPRAS method was used in order to analyze data of the questionnaire that the best choice among various strategies could be chosen. Results represented that the choice of light supply by the lamp with battery source to provide light for city shelters is the best. According to results gotten from this method, choices of light supply by the fossil fuel light, light supply by the urban power source lamp, light supply by the mirror and light supply by fiber optics have been ranked in second, third, fourth and fifth positions, respectively.

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The use of lightweight construction material with high corrosion resistance and low cost plays an important role in the design and construction of marine structures such as waterfronts. One of the most common methods for strengthening the structures is composite fibre reinforced plastic (FRP) sheet that is used for member retrofitting including wood plastic composite (WPC). The WPC material is produced from wood and compressed resin, which has good mechanical properties as well as economic benefits. The main problem of WPC reinforced with FRP sheets is the debonding of the sheet from WPC surface, which leads to premature and non-economic failure in members. One of the existing methods to solve this problem is surface preparation. However, surface preparation of wood plastic composite has some additional problems, such as operational cost, environmental pollution, etc. Therefore, to avoid debonding, another method has been used, known as the grooving method at the lower parts of beams. The laboratory used 50 I-shaped specimens with the same geometrical and mechanical properties. Initially, some slots such as longitudinal, transverse and diagonal grooves were created on the surface of specimens and filled by an epoxy. All beams were armed using one or two layers of GFRP sheets embedded at the lower part and were tested under four-point flexural loading. Grooves of different shapes, various widths and depths as well as the number of reinforcement layers were determined for considering their effect on the beam's behaviour. The results expressed that the debonding of FRP sheets can be delayed by selecting the longitudinal grooves with certain width and depth, which also leads to resistance improvement.