Despite not being taken into account in structural modeling, the complex behavior of masonry affects the seismic performance of structures. The main aim of this study is to evaluate the effects of infilled frames with different percentages of openings on reinforced concrete (RC) moment frames. Initially, an experimental model was constructed and subjected to loading. Afterwards, corresponding numerical analyses were carried out based on the experimental model. A simplified micromodeling method with respect to the numerical simulation of the experimental model was assigned. Subsequently, sensitivity analyses were performed to investigate the effects of the opening ratio on the behavior of intermediate RC moment frames. The analytical results indicate that increasing the percentage of the opening leads to a significant reduction in the lateral strength of the frame. The lateral strength of the masonry wall was negligible in masonry infills with openings greater than 40 %. While prognosticating the behavior of buildings with masonry walls is complicated, determining the behavior of infilled frames with different percentages of openings will make it much easier to predict the damage pattern.

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Background:The eye is one of the most sensitive organs to sulfur mustard (SM) [C 4 H 8 Cl 2 S], and preliminary symptoms of exposure usually become evident in the eyes. In this study we aim to evaluate the possible long-term retinal electrophysiologic complications of SM poisoning in Iranian veterans during Iran-Iraq war (1980)(1981)(1982)(1983)(1984)(1985)(1986)(1987)(1988). Methods:In a cross-sectional study forty Iranian veterans who were exposed to mustard gas during the Iran-Iraq war (1980)(1981)(1982)(1983)(1984)(1985)(1986)(1987)(1988) were included. All the cases underwent complete ocular exam and retinal electrophysiological evaluation, including electroretinography (ERG) and electrooculography (EOG). Data was analyzed using SPSS software. The normal distribution was checked using the Shapiro-Wilk test. Comparison of electrophysiologic values with maximum standard levels was performed using one-sample Student t-test and test of significance was one-tailed.Results: Foreign body sensation (70%), dry eye (50%), photophobia (30%), lacrimation (20%) and pain sensation (10%) were among the common symptoms. ERG showed significant reduced amplitude in rod response, maximal combined response, oscillatory potentials, cone response and 30 Hz flicker waves compared to normal values (p < 0.05). Implicit time of b-wave rod response ERG recording was significantly decreased (p < 0.05). Implicit time of cone response b-wave was within normal limits. In EOG, Arden ratio did not decrease (total average of 2.311 and 2.48 in right and left eyes, respectively). Conclusion:Delayed toxic effects of SM poisoning in the veterans were observed in the retina, but not in the retinal pigment epithelium layer. As the retina is a neural tissue, long-term effects of SM on neural tissues are presumed.

Many unreinforced masonry structures were vulnerable in the past earthquakes and required retrofitting. However, the vulnerability of masonry structures could solve by providing numerous retrofitting approaches, scarcity of appropriate methods that may provide a solution for the historical masonry structures with lesser effects on their façade is vehemently sensible. In this study, two one-third scale masonry wall specimens made by clay bricks were tested under constant vertical and cyclic lateral loading. The specimens consist of an unreinforced wall and a wall retrofitted by GFRP strips. This study investigates the seismic behavior of unreinforced masonry walls before and after using GFRP strips on their bedjoints. To this purpose, various patterns of using GFRP strips have been studied by simplified micro-modeling. The consequence indicates that the proposed retrofitting technique could improve the lateral strength and stiffness of the unreinforced masonry wall along with a considerable increase in the energy dissipation and ductility content, which leads to making a change in the behavior of the wall from brittle to ductile failure. The proposed method could apply to the modern historical structures in which cement mortar has been used as an adhesive between the masonry layers.

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