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Communicative Language Teaching (CLT) is advocated by many applied linguists as a common vehicle to curriculum innovation in many ELT contexts. It represents a change of focus in language teaching from linguistic structures to learners’ need for developing communication skills. In recent years, the Iranian Ministry of Education has introduced the development of a new English curriculum for secondary schools with the aim of establishing the use of communicative activities in language classes. The present study was an attempt to investigate Iranian teachers’ perception of CLT principles and practices through a survey of 75 secondary school teachers in the context of the newly introduced English language curriculum developed based on CLT principles. Based on a combination of quantitative and qualitative data using a semi-structured questionnaire supplemented with interviews with a smaller group of teachers, the results of the survey revealed that a change in classroom arrangements is required before CLT can be practiced in secondary school English classes in Iran. The results also showed that the employment of CLT procedures at the local level is at its beginning stages and might take time to take root. The conclusion is that for the suggested changes in the curriculum to be implemented and realized in English education in Iran, the findings of more comprehensive surveys complemented with observation of teachers’ instructional practices is required to inform the change implementation.

Although some studies have been done on major issues of foreign language teaching in Iran, a large-scale qualitative study is still required to be done particularly with regard to the newly introduced English as a Foreign Language (EFL) curriculum. Therefore, the present study aimed to discover what challenging problems, in-service English teachers encounter in EFL classes and what solutions to these challenges can be suggested based on 169 Iranian EFL teachers' opinions. Data were collected through a written, open-ended questionnaire and semi-structured interviews, and they were thematically analyzed using MAXQDA (Version 2022). Findings revealed that (1) policy makers' ambivalence towards English Language Teaching (ELT), teacher burnout, lack of facilities in schools, lack of teaching aids, and unmotivated students were the main reasons behind the gap between planning and practice of EFL curriculum in Iran; and (2) lowering the starting age of ELT, solving teachers' financial issues, and CLT-based examinations were the most frequently brought up solutions to this gap. Findings were discussed in the area of EFL teaching and some pedagogical implications were also proposed.

Cross-Laminated-Timbers (CLT) absorb/desorb moisture from surrounding atmosphere when exposed to wet/dry conditions; such all engineering massive wood-based products. The moisture gradient occurs due to this process, which is responsible for moisture induced stresses. In the current research work, the moisture induced stresses due to the moisture gradient have been studied in the CLT. The sample panels were made with 5-plys. One and two plys of hydrothermally treated wood at 150°C were placed on both sides as surface layers. Afterwards, the sample panels were exposed to wet to dry cycles (RH of 88 to 32%) and dry to wet cycles (RH of 32 to 88%). Results revealed that the moisture gradient as well as the moisture induced stresses are reduced due to application of the hydrothermally treated laminations on both side of the panels in comparison with control samples.

Bending strength is a critical property of cross laminated timber (CLT) in structural applications, especially in floor of multi-story buildings. Therefore, this study was targeted to evaluate the bending strength of CLT made out of poplar (populous alba). Polyurethane adhesive was used to construct CLT (300 g/m2). The thickness of used planks was 16 mm. The results indicated that modulus of rupture (MOR) and modulus of elasticity (MOE) of CLT with 45o alternating transverse layer were increased 14 and 15%, respectively in comparison with 90o layers. Also, modulus of rupture (MOR) and modulus of elasticity (MOE) of CLT consist of layers with 4cm in width were increased 14 and 5%, respectively in comparison with layers 9cm in width. It was concluded that by using thinner layers, and 45o alternating layer configuration, it is possible to construct CLT with an acceptable bending strength from fast growing trees such as poplar.

In this study, flexural performance of cross-laminated timber (CLT) made out of poplar wood (Populus alba), Polyurethane adhesive and different mechanical connectors were investigated. Amount of adhesive was 300 g/m2. For manufacturing CLT panels, wood planks were air-dried, then four face-bonding surfaces of planks were planed (S4S). Thickness and width of planks were 19 and 100 mm, respectively. The thickness, width and span to depth ratio of Three-layered CLT specimens for bending test were 57, 80 mm and 12, respectively. Bending test was conducted by Instron 4486. The variables of this study were including different connectors (galvanized steel nail, strip brad nails (ST Nails) and coarse thread drywall screw), connector number (2 and 4), adhesive (with and without adhesive) and panel direction (major and minor direction). The results showed that the higher modulus of rupture (MOR) and modulus of elasticity (MOE) were related to major direction of CLT panels connected by 4 screws and adhesive as well the lower of them were related to minor direction of CLT panels connected by 2 ST nails and adhesive. The results also showed that MOR and MOE of CLT panels were changed about 71 and 16, 16 and 400, 1 and 10%, respectively with the change of shear connector, adhesive and number of connector. MOR and MOE in major direction of CLT panels were about 3 and 4 times higher than those in minor direction. The results revealed that MOR of CLT panels meet the specified requirements of ISO 16696-1 standard, however, MOE of them were not comparable with standard value. Hence, it was recommended to perform some comprehensive studies for reinforcing CLT panels made of poplar for increasing their MOE.

In this study, we investigated the effects of glass fiber-reinforced polymers (GFRP) on the withdrawal capacity of wood, lag screws, and steel nails in cross-laminated timber (CLT) made from poplar (Populus alba). We reinforced CLTs with bidirectional GFRP wrap with a grammage of 600 g/m2. The specimens were 75 mm ×75 mm in length and width, and their thicknesses varied depending on the GFRP layers. We used two-component polyurethane glue at a rate of 300 g/m2. ANOVA results showed that the number of GFRP layers had a significant effect on the withdrawal resistance of nails and lag screws (P<0. 05). By increasing the number of GFRP layers in CLT, the withdrawal resistance of the nails, wood screws, and lag screws increased by 280. 4%, 29. 2%, and 83. 3%, respectively, compared to the control CLT samples. The withdrawal resistance of the lag screws was greater than that of the wooden screws and nails. Duncan's Multiple Range Test (MRT) results showed that CLT should be reinforced with at least three layers of GFRP to significantly increase the withdrawal resistance of nails. To significantly increase the withdrawal resistance of lag screws, CLT should be reinforced with at least one layer of GFRP or by three layers for further significant reinforcement.

In this study, the strengthening of cross-laminated timber (CLT) with glass fiber reinforced polymer (GFRP) on the lateral resistance (LR) of the single shear lap joints was investigated. Poplar (Populus alba) layers were used to construct the three-layer CLT. In first step, the effect of GFRP strengthening of CLT panel with three layers of FRP fastened with a lag screw, concrete screw, wood screw, and steel nail at an end distance of 1 cm on the lateral load capacity was investigated. In second step, the effect of the number of GFRP layers on the LR of the joint assembled with the lag screw with an end distance of 1 cm was investigated. Finally, the main effects of panel strength directions (major and minor axes), fastener types (lag screw, concrete screw, wood screw, and steel nail), and end distances (1and 2 cm) and their interaction on LR were investigated. The results showed that LR was increased by 22 to 53% with reinforcement, which was more considerable in joints with smaller diameter fasteners. By increasing the number of GFRP layers from one to three layers, LR was increased by 27%. By increasing the end distance, changing the fastener types and panel directions, LR was changed 114.7%, 219.6%, and 7%, respectively. The interaction of variables on LR showed that by simultaneously changing the fastener types × end distance, LR changed about 447%, which implied the importance of choosing the proper fastener with sufficient end distance to construct the joints with a metal connector such as brackets.