• List of Articles cobiax

      • Open Access Article

        1 - Numerical Modeling of the U-Boot Roof Behavior and Its Comparison with the Steel Deck Roofs, Cobiax roof, and Concrete Slabs
        Saeed Sharifi Ahmad Maleki
        Undoubtedly, one of the main and effective members in building structures is the ceiling, and the type of execution of this part of the structure will play a significant role in the speed and quality of the entire structure. The application of old materials and traditio More
        Undoubtedly, one of the main and effective members in building structures is the ceiling, and the type of execution of this part of the structure will play a significant role in the speed and quality of the entire structure. The application of old materials and traditional construction methods no longer meets the desired speed and design needs. In this study, in addition to introducing the structure of U-Boot roof, an attempt has been made to provide a comparative approach in terms of structural performance with other common roofs such as steel deck roof, concrete slab and Cobiax roof. For this purpose, after ensuring the results of modeling using Abacus software, modeling of numerical samples and comparing them with other common ceilings have been done. The results indicate that by comparing concrete slabs, when increasing the compressive strength of the specimens, the amount of final yield load is increased, but after the yield point, the failure of the specimens was immediate. Then the load capacity has remained constant for the same displacement, and with a decrease of 30% in the number of U-Boots and a 20% increase in compressive strength, the amount of load capacity has increased by about 22.32%. Comparing these specimens with the state without reducing the number of U-Boots, it is determined that for each similar sample, the load bearing capacity has increased by 10%. The U-Boot roof also has higher hardness and load-bearing capacity than other roofs and the concrete slab has the lowest load-bearing capacity in the same displacements. The performance of the steel deck roof and the Cobiax roof is also close in terms of bearing capacity, but in terms of the hardness or gradient of the force-displacement curve, the Cobiax roof has shown more hardness. Manuscript profile
      • Open Access Article

        2 - Comparative evaluation of structural behavior of voided biaxial slab with Steel Deck roofs and RC slabs
        Nima Khalili Ahmad Maleki
        The columns, beam and roof make up the most important members of a building, each of which plays a role in the stability of the structure. These members can be made of different materials that can vary depending on the conditions and type of use of the structure. One of More
        The columns, beam and roof make up the most important members of a building, each of which plays a role in the stability of the structure. These members can be made of different materials that can vary depending on the conditions and type of use of the structure. One of these materials is concrete that is mostly armed by an armature. One of the major drawbacks of using reinforced concrete is to increase the weight of the structure, and most of the efforts to optimize the structure have been made in order to stretch the members. In recent years, studies have been carried out to light concrete structures, most of which are related to roof styling, which has led to the provision of ceilings that, in addition to maintaining high resistance, significantly lower dead loads than Traditional roofs. Reducing the dead load of the roof has significant benefits to the entire structure, the most important of which is to reduce the earthquake force on the structure, which in turn reduces the sections and reduces the dead load of the structure. One of the roof systems is double-sided hollow ceilings or double-sided bubble slabs. To verify the accuracy of the numerical results, the laboratory test was verified and after checking the results, a numerical sample was considered. In this study, a 12-sample numerical model with Abaqus software was compared to compare the Cobiax roofs with steel deck roofs and concrete slabs. The results obtained in this way is no reduction in the number of spheres is about 1.12 percent more cargo capacity. The importance of this value compared to weight loss roof with a 30% reduction in the number of spheres is negligible and can use the sample with a reduced amount of 30% of the balls due to the reduced weight of the structures and effects of the structural elements justify. Also, on average, in all specimens, the specimens after the elastic region and the beginning of cracking, the stiffener of the concrete decreased, and with the increase in displacement, the bearing capacity was almost constant. In the end, the Cobiax roofs, without reducing the number of balloons, have a higher load capacity and hardness than the other two models, with the increase in force, the area under the charts of this model has increased and depreciation is more energy than other specimens. Manuscript profile